Release v1.7.232

HTTP 416: erschoepftes Range-Konflikt-Item macht bounded Clean-Restart statt dauerhaft zu haengen
Nutzer-Report (ultracode-Diagnose, 6-Agenten): ein Item mit "Fehler: HTTP 416" (Range Not Satisfiable) wurde gar nicht mehr erneut versucht und blockierte das ganze Paket ("Entpacken - Ausstehend" bei allen fertigen Geschwistern). Befund code-belegt: nach dem In-Run-416-Budget (maxHttp416Retries) lief das Item in einen Endzustand: - retryLimit>0 (bare "HTTP 416", directLinkRetryMatch=false): direkt terminal "failed" (download-manager ~9442). Der einzige Re-Retry-Pfad recoverRetryableItems() laeuft NUR bei Boot/Start, nie mid-run -> mit autoReconnect=false bleibt es bis zum Neustart "failed". Und da jeder Extract-Zweig auf failed===0 gated, friert EIN failed-Item das ganze Paket ein -> exakt das Screenshot-Symptom. - retryLimit=0 (wrapped "direct_link_retry_exhausted:HTTP 416"): faellt nach dem 416-Budget in den generischen Retry (9349) mit maxGenericErrorRetries= MAX_SAFE_INTEGER -> unbegrenzte futile Re-Unrestricts (haemmert den Hoster, Item kommt nie weiter). Fix: bei erschoepftem 416-Budget an BEIDEN Stellen (gewrappt @9320, bare @9442) nicht mehr terminalisieren bzw. endlos generisch retrien, sondern via neuem escalateHttp416OrFail() einen kompletten Neu-Download von 0 anstossen: Partial loeschen (rmSync), Bytes/Progress/Budget zuruecksetzen, mit Delay re-queuen. Da 416 ein abgelehnter Resume-Range ist, ist der korrekte Weg ein frischer Download ohne Range-Header (kein 416 mehr) statt erneuter Resume. Hart gedeckelt ueber http416FreshRestartByItem (MAX_HTTP416_FRESH_RESTARTS=2, retryLimit- unabhaengig) -> ein wirklich toter Link faellt nach begrenzten sauberen Neustarts terminal, kein Endlos-Hammering. Zaehler wird in start() und beim terminalen Fail geleert. Fresh-Restart-Delay via RD_HTTP416_FRESH_RESTART_DELAY_MS testbar. Sobald das Item den failed-Zustand verlaesst, entsperrt die bestehende failed===0-Logik das Paket-Entpacken von selbst. (Die optionale Haertung "fertige Archiv-Sets trotz failed-Geschwister entpacken" + "Voll-Datei-416 als fertig werten statt neu laden" sind bewusst als Folgeschritt offen.) Tests: Recovery (416 erschoepft -> Clean-Restart -> Item completed, retryLimit>0 bare) + Bounded-Fail (persistentes 416 -> begrenzte Neustarts -> failed, retryLimit=0 wrapped, terminiert statt Endlos). Suite 945 gruen, tsc=6.
2026-06-23 16:13:49 +02:00 · 2026-06-23 16:12:52 +02:00 · 2026-06-23 13:43:04 +02:00 · 2026-06-23 13:42:16 +02:00 · 2026-06-22 03:33:40 +02:00 · 2026-06-22 03:33:00 +02:00
33 changed files with 4039 additions and 142 deletions
--- a/package.json
+++ b/package.json
@ -1,6 +1,6 @@
 {
  "name": "real-debrid-downloader",
-  "version": "1.7.221",
+  "version": "1.7.232",
  "description": "Desktop downloader",
  "main": "build/main/main/main.js",
  "author": "Sucukdeluxe",
--- a/src/main/app-controller.ts
+++ b/src/main/app-controller.ts
@ -1,4 +1,5 @@
 import path from "node:path";
+import os from "node:os";
 import v8 from "node:v8";
 import { app } from "electron";
 import { getDebridLinkApiKeyIds } from "../shared/debrid-link-keys";
@ -9,9 +10,11 @@ import {
  DebridAccountStatus,
  DebridProvider,
  DuplicatePolicy,
+  EnableRemoteDiagnosticsInput,
  HistoryEntry,
  PackagePriority,
  ParsedPackageInput,
+  RemoteDiagnosticsInfo,
  SessionStats,
  StartConflictEntry,
  StartConflictResolutionResult,
@ -36,12 +39,13 @@ import { getItemLogPath, initItemLogs, shutdownItemLogs } from "./item-log";
 import { getPackageLogPath, initPackageLogs, shutdownPackageLogs } from "./package-log";
 import { initSessionLog, getSessionLogPath, shutdownSessionLog } from "./session-log";
 import { MegaWebFallback } from "./mega-web-fallback";
-import { addHistoryEntry, addHistoryEntryForRetention, cancelPendingAsyncSaves, clearHistory, createStoragePaths, loadHistory, loadHistoryForRetention, loadSession, loadSettings, normalizeHistoryEntry, normalizeLoadedSession, normalizeLoadedSessionTransientFields, normalizeSettings, removeHistoryEntry, resetHistoryForRetention, saveHistory, saveSession, saveSettings } from "./storage";
+import { addHistoryEntry, addHistoryEntryForRetention, cancelPendingAsyncSaves, clearHistory, createStoragePaths, loadHistory, loadHistoryForRetention, loadSessionWithStatus, loadSettings, normalizeHistoryEntry, normalizeLoadedSession, normalizeLoadedSessionTransientFields, normalizeSettings, removeHistoryEntry, resetHistoryForRetention, saveHistory, saveSession, saveSettings } from "./storage";
 import { abortActiveUpdateDownload, checkGitHubUpdate, installLatestUpdate } from "./update";
 import { runInstallWithResume } from "./update-install-flow";
-import { rotateDebugToken, startDebugServer, stopDebugServer } from "./debug-server";
+import { rotateDebugToken, startDebugServer, stopDebugServer, restartDebugServer, getDebugServerRuntimeStatus, getActiveDebugToken, getDebugAllowlist, writeDebugServerConfig, clearDebugToken } from "./debug-server";
+import { encodeConnectionCode, loadRemoteMeta, saveRemoteMeta } from "./connection-code";
 import { encryptBackup, decryptBackup } from "./backup-crypto";
-import { buildBackupPayload, planBackupImport } from "./backup-payload";
+import { buildBackupPayload, planBackupImport, resolveMcpRemoteRestore, BackupMcpRemote } from "./backup-payload";
 import { getAuditLogPath, initAuditLog, logAuditEvent, shutdownAuditLog } from "./audit-log";
 import { initAccountRotationLog, shutdownAccountRotationLog } from "./account-rotation-log";
 import { initConversionLog, shutdownConversionLog } from "./conversion-trace";
@ -108,7 +112,8 @@ export class AppController {
    initTraceLog(this.storagePaths.baseDir);
    this.settings = loadSettings(this.storagePaths);
    resetHistoryForRetention(this.storagePaths, this.settings.historyRetentionMode);
-    const session = loadSession(this.storagePaths);
+    const loadResult = loadSessionWithStatus(this.storagePaths);
+    const session = loadResult.session;
    this.megaWebFallback = new MegaWebFallback(() => ({
      login: this.settings.megaLogin,
      password: this.settings.megaPassword
@ -122,6 +127,7 @@ export class AppController {
      realDebridWebUnrestrict: (link: string, signal?: AbortSignal) => this.realDebridWebFallback.unrestrict(link, signal),
      bestDebridWebUnrestrict: (link: string, signal?: AbortSignal) => this.bestDebridWebFallback.unrestrict(link, signal),
      invalidateMegaSession: () => this.megaWebFallback.invalidateSession(),
+      protectEmptyClobber: loadResult.status === "empty-unreadable",
      onHistoryEntry: (entry: HistoryEntry) => {
        addHistoryEntryForRetention(this.storagePaths, this.settings.historyRetentionMode, entry, this.historyLimits());
      }
@ -174,21 +180,13 @@ export class AppController {
    if (this.settings.autoResumeOnStart) {
      const snapshot = this.manager.getSnapshot();
      const hasPending = Object.values(snapshot.session.items).some((item) => item.status === "queued" || item.status === "reconnect_wait");
-      if (hasPending) {
-        void this.manager.getStartConflicts().then((conflicts) => {
-          const hasConflicts = conflicts.length > 0;
-          if (this.hasAnyProviderToken(this.settings) && !hasConflicts) {
+      if (hasPending && this.hasAnyProviderToken(this.settings)) {
        if (this.onStateHandler) {
-              logger.info("Auto-Resume beim Start aktiviert (nach Konflikt-Check)");
-              void this.manager.start().catch((err) => logger.warn(`Auto-Resume Start Fehler: ${String(err)}`));
+          this.beginAutoResume();
        } else {
          this.autoResumePending = true;
          logger.info("Auto-Resume beim Start vorgemerkt");
        }
-          } else if (hasConflicts) {
-            logger.info("Auto-Resume übersprungen: Start-Konflikte erkannt");
-          }
-        }).catch((err) => logger.warn(`getStartConflicts Fehler (constructor): ${String(err)}`));
      }
    }
  }
@ -245,14 +243,27 @@ export class AppController {
      handler(this.manager.getSnapshot());
      if (this.autoResumePending) {
        this.autoResumePending = false;
-        void this.manager.start().catch((err) => logger.warn(`Auto-Resume Start Fehler: ${String(err)}`));
-        logger.info("Auto-Resume beim Start aktiviert");
+        this.beginAutoResume();
      } else {
        this.manager.triggerIdleExtractions();
      }
    }
  }

+  private beginAutoResume(): void {
+    void this.manager.getStartConflicts().then((conflicts) => {
+      const excludePackageIds = new Set(conflicts.map((conflict) => conflict.packageId));
+      if (excludePackageIds.size > 0) {
+        const names = conflicts.map((conflict) => conflict.packageName).join(", ");
+        logger.info(`Auto-Resume: ${excludePackageIds.size} Paket(e) mit Start-Konflikt zurückgehalten (${names}); übrige Pakete starten`);
+      } else {
+        logger.info("Auto-Resume beim Start aktiviert (keine Start-Konflikte)");
+      }
+      void this.manager.start(excludePackageIds.size > 0 ? { excludePackageIds } : undefined)
+        .catch((err) => logger.warn(`Auto-Resume Start Fehler: ${String(err)}`));
+    }).catch((err) => logger.warn(`Auto-Resume Konflikt-Check Fehler: ${String(err)}`));
+  }
+
  public getSnapshot(): UiSnapshot {
    return this.manager.getSnapshot();
  }
@ -291,6 +302,100 @@ export class AppController {
    return rotated;
  }

+  private getSuggestedRemoteHosts(): string[] {
+    const hosts: string[] = [];
+    try {
+      const interfaces = os.networkInterfaces();
+      for (const entry of Object.values(interfaces)) {
+        for (const net of entry || []) {
+          if (net.family === "IPv4" && !net.internal && net.address) {
+            hosts.push(net.address);
+          }
+        }
+      }
+    } catch {
+    }
+    return [...new Set(hosts)];
+  }
+
+  public getRemoteDiagnostics(): RemoteDiagnosticsInfo {
+    const status = getDebugServerRuntimeStatus();
+    const meta = loadRemoteMeta(this.storagePaths.baseDir);
+    const token = getActiveDebugToken();
+    const allowlist = getDebugAllowlist();
+    const suggestedHosts = this.getSuggestedRemoteHosts();
+    const host = meta.publicHost
+      || (status.localOnly ? "127.0.0.1" : (suggestedHosts[0] || status.host));
+    const code = (status.hasToken && token && host)
+      ? encodeConnectionCode({ host, port: status.port, token, name: meta.name || undefined })
+      : null;
+    return {
+      status,
+      code,
+      publicHost: meta.publicHost,
+      name: meta.name,
+      allowlist,
+      suggestedHosts
+    };
+  }
+
+  public async enableRemoteDiagnostics(input: EnableRemoteDiagnosticsInput): Promise<RemoteDiagnosticsInfo> {
+    const baseDir = this.storagePaths.baseDir;
+    const port = input.port && Number.isInteger(input.port) && input.port >= 1024 && input.port <= 65535
+      ? input.port
+      : 9868;
+    const bindHost = input.hostMode === "network" ? "0.0.0.0" : "127.0.0.1";
+    const allowlist = (input.allowlist || []).map((entry) => entry.trim()).filter((entry) => entry.length > 0);
+    if (input.hostMode === "network" && allowlist.length === 0) {
+      throw new Error("Netzwerk-Freigabe erfordert mindestens eine erlaubte IP oder CIDR in der Allowlist.");
+    }
+    let token = getActiveDebugToken();
+    if (!token || input.rotateToken) {
+      token = rotateDebugToken(baseDir).token;
+    }
+    writeDebugServerConfig({ host: bindHost, port, allowlist });
+    saveRemoteMeta(baseDir, { publicHost: (input.publicHost || "").trim(), name: (input.name || "").trim() });
+    await restartDebugServer();
+    this.audit("WARN", "Ferndiagnose aktiviert", {
+      host: bindHost,
+      port,
+      allowlistCount: allowlist.length,
+      localOnly: input.hostMode === "local"
+    });
+    return this.getRemoteDiagnostics();
+  }
+
+  public async disableRemoteDiagnostics(): Promise<RemoteDiagnosticsInfo> {
+    clearDebugToken();
+    await restartDebugServer();
+    this.audit("WARN", "Ferndiagnose deaktiviert (Token entfernt)");
+    return this.getRemoteDiagnostics();
+  }
+
+  public async rotateRemoteDiagnosticsToken(): Promise<RemoteDiagnosticsInfo> {
+    rotateDebugToken(this.storagePaths.baseDir);
+    await restartDebugServer();
+    this.audit("WARN", "Ferndiagnose-Token rotiert");
+    return this.getRemoteDiagnostics();
+  }
+
+  private restoreMcpRemoteFromBackup(section: unknown, restartNow: boolean): void {
+    const restore = resolveMcpRemoteRestore(section);
+    if (!restore) {
+      return;
+    }
+    writeDebugServerConfig({ host: restore.host, port: restore.port, allowlist: restore.allowlist });
+    if (restartNow) {
+      void restartDebugServer().catch(() => {});
+    }
+    this.audit("INFO", "Ferndiagnose-Einstellungen aus Backup wiederhergestellt", {
+      port: restore.port ?? null,
+      allowlistCount: restore.allowlist?.length ?? 0,
+      host: restore.host ?? "unveraendert",
+      restartNow
+    });
+  }
+
  public getDebugSetupCheck(): DebugSetupCheckResult {
    return getDebugSetupCheck(this.storagePaths.baseDir);
  }
@ -643,13 +748,22 @@ public async checkDebridAccounts(): Promise<DebridAccountStatus[]> {
  }

  public exportBackup(): Buffer {
-    const includeDownloads = Boolean(this.settings.backupIncludeDownloads);
+    let mcpRemote: BackupMcpRemote | undefined;
+    if (Boolean(this.settings.backupIncludeMcp)) {
+      const status = getDebugServerRuntimeStatus();
+      mcpRemote = {
+        allowlist: getDebugAllowlist(),
+        port: status.port,
+        hostMode: status.host === "0.0.0.0" ? "network" : "local"
+      };
+    }
    const payloadObj = buildBackupPayload({
      settings: { ...this.settings },
      appVersion: APP_VERSION,
      exportedAt: new Date().toISOString(),
      session: this.manager.getSession(),
-      history: loadHistoryForRetention(this.storagePaths, this.settings.historyRetentionMode, this.historyLimits())
+      history: loadHistoryForRetention(this.storagePaths, this.settings.historyRetentionMode, this.historyLimits()),
+      mcpRemote
    });
    this.audit("INFO", "Backup exportiert", {
      kind: payloadObj.kind,
@ -723,6 +837,7 @@ public async checkDebridAccounts(): Promise<DebridAccountStatus[]> {
      this.settings = restoredSettings;
      saveSettings(this.storagePaths, this.settings);
      this.manager.setSettings(this.settings, { suppressRetroactiveCleanup: true });
+      this.restoreMcpRemoteFromBackup(parsed.mcpRemote, true);
      this.audit("INFO", "Backup importiert (nur Einstellungen)", {
        accountSummary: buildAccountSummary(this.settings)
      });
@ -759,6 +874,8 @@ public async checkDebridAccounts(): Promise<DebridAccountStatus[]> {

    resetHistoryForRetention(this.storagePaths, this.settings.historyRetentionMode);

+    this.restoreMcpRemoteFromBackup(parsed.mcpRemote, false);
+
    this.manager.skipShutdownPersist = true;
    this.manager.blockAllPersistence = true;
    logger.info("Backup wiederhergestellt — App startet automatisch neu");
--- a/src/main/backup-payload.ts
+++ b/src/main/backup-payload.ts
@ -2,6 +2,12 @@ import type { AppSettings, SessionState, HistoryEntry } from "../shared/types";

 export type BackupKind = "full" | "settings-only";

+export interface BackupMcpRemote {
+  allowlist: string[];
+  port: number;
+  hostMode: "local" | "network";
+}
+
 export interface BackupPayload {
  version: 2;
  kind: BackupKind;
@ -10,6 +16,7 @@ export interface BackupPayload {
  settings: AppSettings;
  session?: SessionState;
  history?: HistoryEntry[];
+  mcpRemote?: BackupMcpRemote;
 }

 export interface BuildBackupInput {
@ -19,6 +26,7 @@ export interface BuildBackupInput {
  /** Only bundled when includeDownloads is true. */
  session: SessionState;
  history: HistoryEntry[];
+  mcpRemote?: BackupMcpRemote;
 }

 /**
@ -40,9 +48,39 @@ export function buildBackupPayload(input: BuildBackupInput): BackupPayload {
    base.session = input.session;
    base.history = input.history;
  }
+  if (Boolean(input.settings.backupIncludeMcp) && input.mcpRemote) {
+    base.mcpRemote = input.mcpRemote;
+  }
  return base;
 }

+export interface McpRemoteRestore {
+  host?: "127.0.0.1" | "0.0.0.0";
+  port?: number;
+  allowlist?: string[];
+}
+
+export function resolveMcpRemoteRestore(section: unknown): McpRemoteRestore | null {
+  if (!section || typeof section !== "object") {
+    return null;
+  }
+  const s = section as { allowlist?: unknown; port?: unknown; hostMode?: unknown };
+  const allowlist = Array.isArray(s.allowlist)
+    ? s.allowlist.filter((entry): entry is string => typeof entry === "string" && entry.trim().length > 0).map((entry) => entry.trim())
+    : undefined;
+  const port = (typeof s.port === "number" && Number.isInteger(s.port) && s.port >= 1024 && s.port <= 65535) ? s.port : undefined;
+  let host: "127.0.0.1" | "0.0.0.0" | undefined;
+  if (s.hostMode === "network") {
+    host = allowlist && allowlist.length > 0 ? "0.0.0.0" : "127.0.0.1";
+  } else if (s.hostMode === "local") {
+    host = "127.0.0.1";
+  }
+  if (host === undefined && port === undefined && allowlist === undefined) {
+    return null;
+  }
+  return { host, port, allowlist };
+}
+
 export interface ImportPlan {
  valid: boolean;
  /** Restore the download list (session + history) and relaunch. */
--- a/src/main/connection-code.ts
+++ b/src/main/connection-code.ts
@ -0,0 +1,59 @@
+import fs from "node:fs";
+import path from "node:path";
+
+const PREFIX = "rddiag:v1:";
+
+function base64urlEncode(value: string): string {
+  return Buffer.from(value, "utf8")
+    .toString("base64")
+    .replace(/\+/g, "-")
+    .replace(/\//g, "_")
+    .replace(/=+$/, "");
+}
+
+export interface ConnectionCodeInput {
+  host: string;
+  port: number;
+  token: string;
+  name?: string;
+  scheme?: "http" | "https";
+  fingerprint?: string;
+}
+
+export function encodeConnectionCode(input: ConnectionCodeInput): string {
+  const host = String(input.host || "").trim();
+  if (!host) throw new Error("Host fehlt fuer Verbindungscode");
+  const port = Number(input.port);
+  if (!Number.isInteger(port) || port < 1 || port > 65535) throw new Error("Port ungueltig fuer Verbindungscode");
+  if (!input.token) throw new Error("Token fehlt fuer Verbindungscode");
+  const payload: Record<string, unknown> = { v: 1, h: host, p: port, t: input.token };
+  if (input.name) payload.n = String(input.name);
+  if (input.fingerprint) payload.fp = String(input.fingerprint);
+  if (input.scheme && input.scheme !== "http") payload.s = String(input.scheme);
+  return PREFIX + base64urlEncode(JSON.stringify(payload));
+}
+
+export interface RemoteMeta {
+  publicHost: string;
+  name: string;
+}
+
+function remoteMetaPath(baseDir: string): string {
+  return path.join(baseDir, "debug_remote.json");
+}
+
+export function loadRemoteMeta(baseDir: string): RemoteMeta {
+  try {
+    const parsed = JSON.parse(fs.readFileSync(remoteMetaPath(baseDir), "utf8"));
+    return {
+      publicHost: String(parsed.publicHost || ""),
+      name: String(parsed.name || "")
+    };
+  } catch {
+    return { publicHost: "", name: "" };
+  }
+}
+
+export function saveRemoteMeta(baseDir: string, meta: RemoteMeta): void {
+  fs.writeFileSync(remoteMetaPath(baseDir), JSON.stringify({ publicHost: meta.publicHost, name: meta.name }, null, 2), "utf8");
+}
--- a/src/main/constants.ts
+++ b/src/main/constants.ts
@ -109,6 +109,7 @@ export function defaultSettings(): AppSettings {
    hideExtractedItems: true,
    confirmDeleteSelection: true,
    backupIncludeDownloads: false,
+    backupIncludeMcp: false,
    notifyUrl: "",
    notifyMention: "",
    notifyOnPackageCompleted: false,
--- a/src/main/debrid.ts
+++ b/src/main/debrid.ts
@ -288,6 +288,7 @@ type MegaDebridCooldownCategory = "invalid" | "rate_limit" | "quota" | "temporar
 type MegaDebridCooldownDetail = { until: number; message: string; category: MegaDebridCooldownCategory; untilRestart?: boolean };
 const megaDebridAccountCooldowns = new Map<string, MegaDebridCooldownDetail>();
 const MEGA_DEBRID_ACCOUNT_COOLDOWN_MS = 120_000;
+const MEGA_DEBRID_SLOW_LINK_RETRY_MS = 120_000;
 const MEGA_DEBRID_INVALID_ACCOUNT_COOLDOWN_MS = 60 * 60 * 1000;

 // A Mega-Web account abort (the shared unrestrict timeout firing while this
@ -301,7 +302,7 @@ function getMegaDebridAbortMinRunMs(): number {
 }

 const megaDebridEmptyResponseStreaks = new Map<string, number>();
-export const MEGA_DEBRID_EMPTY_STREAK_UNTIL_RESTART = 3;
+export const MEGA_DEBRID_EMPTY_STREAK_UNTIL_RESTART = 10;

 let megaDebridRotationCursor = 0;
 let megaDebridStickyCount = 0;
@ -338,6 +339,25 @@ export function resetMegaDebridRuntimeStateForTests(): void {
  megaDebridInFlight.clear();
 }

+export function getMegaDebridInFlightCountForMode(mode: "api" | "web"): number {
+  const suffix = `:${mode}`;
+  let total = 0;
+  for (const [key, count] of megaDebridInFlight) {
+    if (key.endsWith(suffix)) {
+      total += count;
+    }
+  }
+  return total;
+}
+
+export function primeMegaDebridInFlightForTests(key: string, count: number): void {
+  if (count <= 0) {
+    megaDebridInFlight.delete(key);
+    return;
+  }
+  megaDebridInFlight.set(key, count);
+}
+
 export function pruneExpiredMegaDebridRuntimeState(now = Date.now()): number {
  let removed = 0;
  const grace = 60 * 60 * 1000;
@ -422,6 +442,106 @@ export function getMegaDebridAccountCooldownState(
  };
 }

+export interface ProviderRuntimeCooldown {
+  untilMs: number;
+  remainingMs: number;
+  message: string;
+  category: string;
+  untilRestart?: boolean;
+}
+
+export interface ProviderRuntimeSnapshot {
+  capturedAtMs: number;
+  megaDebrid: {
+    rotationCursor: number;
+    stickyCount: number;
+    accounts: Array<{
+      key: string;
+      cooldown: ProviderRuntimeCooldown | null;
+      inFlight: number;
+      emptyResponseStreak: number;
+    }>;
+  };
+  debridLink: {
+    keys: Array<{
+      keyId: string;
+      cooldown: ProviderRuntimeCooldown | null;
+      runtimeStatus: { state: string; detail: string; updatedAt: number } | null;
+    }>;
+    hostCooldowns: Array<{ key: string; cooldown: ProviderRuntimeCooldown }>;
+  };
+}
+
+export function getProviderRuntimeSnapshot(now = Date.now()): ProviderRuntimeSnapshot {
+  const megaKeys = new Set<string>([
+    ...megaDebridAccountCooldowns.keys(),
+    ...megaDebridInFlight.keys(),
+    ...megaDebridEmptyResponseStreaks.keys()
+  ]);
+  const megaAccounts = [...megaKeys].sort().map((key) => {
+    const detail = megaDebridAccountCooldowns.get(key);
+    return {
+      key,
+      cooldown: detail
+        ? {
+            untilMs: detail.until,
+            remainingMs: Math.max(0, detail.until - now),
+            message: detail.message,
+            category: detail.category,
+            untilRestart: detail.untilRestart === true
+          }
+        : null,
+      inFlight: megaDebridInFlight.get(key) ?? 0,
+      emptyResponseStreak: megaDebridEmptyResponseStreaks.get(key) ?? 0
+    };
+  });
+
+  const dlKeyIds = new Set<string>([
+    ...debridLinkKeyCooldowns.keys(),
+    ...debridLinkKeyRuntimeStatuses.keys()
+  ]);
+  const dlKeys = [...dlKeyIds].sort().map((keyId) => {
+    const until = Number(debridLinkKeyCooldowns.get(keyId) || 0);
+    const detail = debridLinkKeyCooldownDetails.get(keyId);
+    const status = debridLinkKeyRuntimeStatuses.get(keyId) || null;
+    return {
+      keyId,
+      cooldown: until > 0
+        ? {
+            untilMs: until,
+            remainingMs: Math.max(0, until - now),
+            message: detail?.message ?? "",
+            category: detail?.category ?? "temporary"
+          }
+        : null,
+      runtimeStatus: status ? { state: status.state, detail: status.detail, updatedAt: status.updatedAt } : null
+    };
+  });
+
+  const dlHostCooldowns = [...debridLinkKeyHostCooldowns].map(([key, until]) => {
+    const detail = debridLinkKeyHostCooldownDetails.get(key);
+    return {
+      key,
+      cooldown: {
+        untilMs: until,
+        remainingMs: Math.max(0, until - now),
+        message: detail?.message ?? "",
+        category: detail?.category ?? "temporary"
+      }
+    };
+  });
+
+  return {
+    capturedAtMs: now,
+    megaDebrid: {
+      rotationCursor: megaDebridRotationCursor,
+      stickyCount: megaDebridStickyCount,
+      accounts: megaAccounts
+    },
+    debridLink: { keys: dlKeys, hostCooldowns: dlHostCooldowns }
+  };
+}
+
 const LINKSNAPPY_API_BASE = "https://linksnappy.com/api";

 const PROVIDER_LABELS: Record<DebridProvider, string> = {
@ -2068,15 +2188,33 @@ class MegaDebridClient {
      } catch (error) {
        const elapsedMs = Date.now() - testStartedAt;
        const abortText = compactErrorText(error).replace(/^Error:\s*/i, "");
-        // Timeout/abort on THIS account (the shared unrestrict signal fired). Cool
-        // the account down — if it actually ran, not a quick user-cancel — so the
-        // download-manager's retry rotates to the NEXT account instead of hammering
-        // this one. The shared signal is now aborted, so we stop this pass; the
-        // retry runs the rotation fresh with this account skipped. A genuine cancel
-        // is not retried by the caller, so the cooldown is harmless there.
+        // Timeout/abort on THIS account (the shared unrestrict timeout fired). The
+        // account-wide cooldown exists ONLY to make the retry rotate to another
+        // account — so it is set only when another usable account actually exists.
+        // With no rotation target (single account / all others busy), cooling the
+        // sole account would freeze EVERY queued item while the account is healthy;
+        // a >60s timeout is a slow-LINK signal, not an unhealthy-account signal, so
+        // we park just this link (mega_debrid_slow_link) and leave the account free
+        // for other items. A quick user-cancel (below the min run) parks nothing.
        if (/aborted/i.test(abortText) && !/timeout/i.test(abortText)) {
          const ranLongEnough = elapsedMs >= getMegaDebridAbortMinRunMs();
-          if (ranLongEnough) {
+          const otherUsableAccounts = orderedEntries.reduce((count, candidate) => {
+            if (candidate.account.id === account.id) {
+              return count;
+            }
+            if (isMegaDebridAccountDisabled(settings, candidate.account.id)) {
+              return count;
+            }
+            if (isMegaDebridAccountDailyLimitReached(settings, candidate.account.id)) {
+              return count;
+            }
+            if (getMegaDebridAccountCooldownState(`${candidate.account.id}:${mode}`)) {
+              return count;
+            }
+            return count + 1;
+          }, 0);
+          const rotateToAnotherAccount = ranLongEnough && otherUsableAccounts > 0;
+          if (rotateToAnotherAccount) {
            setMegaDebridAccountCooldownState(cooldownKey, MEGA_DEBRID_ACCOUNT_COOLDOWN_MS, `Abbruch/Timeout nach ${Math.ceil(elapsedMs / 1000)}s`, "temporary");
          }
          traceConversionPhase({
@ -2085,15 +2223,18 @@ class MegaDebridClient {
            account: rotationLabel,
            workMs: elapsedMs,
            outcome: "aborted",
-            detail: `${abortText}${ranLongEnough ? ` cd=${Math.ceil(MEGA_DEBRID_ACCOUNT_COOLDOWN_MS / 1000)}s` : ""}`
+            detail: `${abortText}${rotateToAnotherAccount ? ` cd=${Math.ceil(MEGA_DEBRID_ACCOUNT_COOLDOWN_MS / 1000)}s` : ranLongEnough ? ` slowlink=${Math.ceil(MEGA_DEBRID_SLOW_LINK_RETRY_MS / 1000)}s` : ""}`
          });
          failures.push(`Mega-Debrid${accountLabel}: ${abortText}`);
          logAccountRotation("WARN", providerName, rotationLabel, "TIMEOUT_COOLDOWN", {
            elapsedMs,
            reason: abortText,
-            cooldownSec: ranLongEnough ? Math.ceil(MEGA_DEBRID_ACCOUNT_COOLDOWN_MS / 1000) : 0,
-            next: "naechster Account beim Retry"
+            cooldownSec: rotateToAnotherAccount ? Math.ceil(MEGA_DEBRID_ACCOUNT_COOLDOWN_MS / 1000) : 0,
+            next: rotateToAnotherAccount ? "naechster Account beim Retry" : "Einzel-Retry (Account bleibt fuer andere Items frei)"
          });
+          if (ranLongEnough && !rotateToAnotherAccount) {
+            throw new Error(`mega_debrid_slow_link:${MEGA_DEBRID_SLOW_LINK_RETRY_MS}:Mega-Debrid${accountLabel}: ${abortText}`);
+          }
          throw new Error(`Mega-Debrid${accountLabel}: ${abortText}`);
        }
        const failure = MegaDebridClient.classifyAccountFailure(error);
@ -2113,7 +2254,7 @@ class MegaDebridClient {
          const streak = recordMegaDebridEmptyResponseStreak(cooldownKey);
          if (streak >= MEGA_DEBRID_EMPTY_STREAK_UNTIL_RESTART) {
            parkUntilRestart = true;
-            parkMessage = `Tageslimit erreicht (${streak}x kein Server/leere Antwort) — bis zum Tagesreset gesperrt`;
+            parkMessage = `Tageslimit erreicht (${streak}x leere Antwort in Folge) — bis zum Tagesreset gesperrt`;
          }
        } else {
          clearMegaDebridEmptyResponseStreak(cooldownKey);
@ -2207,6 +2348,10 @@ class MegaDebridClient {
      return { fatal: false, cooldownMs: 0, message: germanMegaDebridResolveReason(errorText), category: "temporary" };
    }

+    if (/lieferte kein ergebnis|linkgenerierung[^.]*kein ergebnis/i.test(errorText)) {
+      return { fatal: false, cooldownMs: 0, message: germanMegaDebridResolveReason(errorText), category: "temporary" };
+    }
+
    if (/permanent ungültig|hosternotavailable|file.?not.?found|file.?unavailable|link.?is.?dead/i.test(errorText)) {
      return { fatal: true, cooldownMs: 0, message: errorText, category: "skip" };
    }
--- a/src/main/debug-server.ts
+++ b/src/main/debug-server.ts
@ -15,6 +15,8 @@ import { createStoragePaths, loadHistory, loadSettings } from "./storage";
 import { buildAccountSummary, buildRedactedSettingsPayload, buildStatsPayload, summarizeHistoryEntry } from "./support-data";
 import { buildSupportBundle, getSupportBundleDefaultFileName } from "./support-bundle";
 import { getTraceConfig, getTraceConfigPath, getTraceLogPath, logTraceEvent, setTraceEnabled, updateTraceConfig } from "./trace-log";
+import { getConversionLogPath } from "./conversion-trace";
+import { getProviderRuntimeSnapshot } from "./debrid";
 import { getWindowsHostDiagnostics } from "./windows-host-diagnostics";
 import type { DownloadManager } from "./download-manager";
 import type { DownloadItem, PackageEntry, UiSnapshot } from "../shared/types";
@ -43,12 +45,14 @@ const DEBUG_ENDPOINTS: DebugEndpointDescriptor[] = [
  { method: "GET", path: "/logs/rename", queryExample: "lines=100&grep=keyword", description: "Reads the dedicated rename and MKV move log." },
  { method: "GET", path: "/logs/trace", queryExample: "lines=100&grep=keyword", description: "Reads the optional support trace log." },
  { method: "GET", path: "/logs/session", queryExample: "lines=100&grep=keyword", description: "Reads the session log tail." },
+  { method: "GET", path: "/logs/conversion", queryExample: "lines=100&grep=keyword", description: "Reads the per-item link conversion/unrestrict lifecycle log (token, API getLink, web, account rotation, aborts with timings)." },
  { method: "GET", path: "/logs/package", queryExample: "package=Release&lines=100&grep=keyword", description: "Reads the package log for a specific package name or id." },
  { method: "GET", path: "/logs/item", queryExample: "item=episode.part2.rar&lines=100&grep=keyword", description: "Reads the item log for a specific file name or item id." },
  { method: "GET", path: "/errors", queryExample: "level=ERROR&limit=100", description: "Returns the in-memory ring of the most recent WARN/ERROR log lines." },
  { method: "GET", path: "/trace/config", queryExample: "enable=1&note=support&durationMinutes=120", description: "Reads or updates the support trace configuration." },
  { method: "GET", path: "/settings", description: "Returns a redacted settings snapshot without raw secrets." },
  { method: "GET", path: "/accounts", description: "Returns a redacted account/provider configuration summary." },
+  { method: "GET", path: "/providers", description: "Live provider runtime state: per-account/key cooldowns (until/remaining/reason/category), in-flight depth, Mega rotation cursor, empty-response streaks. The 'why is it cooling down right now' view." },
  { method: "GET", path: "/stats", description: "Returns live session stats plus persisted all-time totals." },
  { method: "GET", path: "/history", queryExample: "limit=50&status=completed", description: "Returns history entries with optional filters." },
  { method: "GET", path: "/status", description: "Returns a live high-level status overview." },
@ -65,6 +69,16 @@ let authToken = "";
 let bindHost = DEFAULT_HOST;
 let bindPort = DEFAULT_PORT;
 let runtimeBaseDir = "";
+let allowlist: string[] = [];
+
+export interface DebugServerRuntimeStatus {
+  running: boolean;
+  host: string;
+  port: number;
+  hasToken: boolean;
+  localOnly: boolean;
+  allowlistCount: number;
+}

 function getStoragePaths() {
  return createStoragePaths(runtimeBaseDir);
@ -140,6 +154,94 @@ function getHost(baseDir: string): string {
  return DEFAULT_HOST;
 }

+function getAllowlistPath(baseDir: string = runtimeBaseDir): string {
+  return path.join(baseDir, "debug_allowlist.txt");
+}
+
+function loadAllowlist(baseDir: string): string[] {
+  try {
+    return fs.readFileSync(getAllowlistPath(baseDir), "utf8")
+      .split(/\r?\n/)
+      .map((line) => line.trim())
+      .filter((line) => line.length > 0 && !line.startsWith("#"));
+  } catch {
+    return [];
+  }
+}
+
+function normalizeIp(ip: string): string {
+  return String(ip || "").trim().replace(/^::ffff:/i, "").toLowerCase();
+}
+
+function isLoopbackIp(ip: string): boolean {
+  const x = normalizeIp(ip);
+  return x === "::1" || x === "localhost" || x.startsWith("127.");
+}
+
+function ipv4ToInt(ip: string): number | null {
+  const parts = ip.split(".");
+  if (parts.length !== 4) {
+    return null;
+  }
+  let result = 0;
+  for (const part of parts) {
+    const value = Number(part);
+    if (!Number.isInteger(value) || value < 0 || value > 255) {
+      return null;
+    }
+    result = (result * 256) + value;
+  }
+  return result >>> 0;
+}
+
+function matchIpRule(clientIp: string, rule: string): boolean {
+  const client = normalizeIp(clientIp);
+  const r = rule.trim().toLowerCase();
+  if (!r) {
+    return false;
+  }
+  if (r === "*" || r === "0.0.0.0/0") {
+    return true;
+  }
+  if (r === client) {
+    return true;
+  }
+  const slash = r.indexOf("/");
+  if (slash > 0) {
+    const baseInt = ipv4ToInt(r.slice(0, slash));
+    const clientInt = ipv4ToInt(client);
+    const bits = Number(r.slice(slash + 1));
+    if (baseInt === null || clientInt === null || !Number.isInteger(bits) || bits < 0 || bits > 32) {
+      return false;
+    }
+    if (bits === 0) {
+      return true;
+    }
+    const mask = bits === 32 ? 0xffffffff : (~((1 << (32 - bits)) - 1)) >>> 0;
+    return (clientInt & mask) === (baseInt & mask);
+  }
+  return false;
+}
+
+export function evaluateClientAllowed(clientIp: string, rules: string[]): boolean {
+  const client = normalizeIp(clientIp);
+  if (isLoopbackIp(client) || client === "") {
+    return true;
+  }
+  if (rules.length === 0) {
+    return false;
+  }
+  return rules.some((rule) => matchIpRule(client, rule));
+}
+
+export function getPeerIp(req: http.IncomingMessage): string {
+  return normalizeIp(req.socket?.remoteAddress || "");
+}
+
+function isClientAllowed(clientIp: string): boolean {
+  return evaluateClientAllowed(clientIp, allowlist);
+}
+
 function checkAuth(req: http.IncomingMessage): boolean {
  if (!authToken) {
    return false;
@ -258,6 +360,7 @@ function buildAiManifest(baseDir: string): Record<string, unknown> {
      "Call /meta first to confirm the server is reachable and to re-read the endpoint list.",
      "Use /self-check or /debug/setup to quickly verify whether token, host, manifest, trace, disk space, and log sizes are in a good support state.",
      "Use /diagnostics for an overview, then drill into /logs/item, /logs/package, /logs/rename, /status, /packages, /items, /settings, /accounts, /stats, /history, or /logs/trace.",
+      "For provider stalls/cooldowns, call /providers for the live cooldown state (until/remaining/reason per account/key) and /logs/conversion for the per-item resolve lifecycle (token, API, web, rotation, aborts with timings).",
      "If a full handoff is needed, download /support/bundle as a ZIP."
    ],
    auth: {
@ -461,6 +564,19 @@ function handleRequest(req: http.IncomingMessage, res: http.ServerResponse): voi
    return;
  }

+  const peerIp = getPeerIp(req);
+  if (!isClientAllowed(peerIp)) {
+    if (traceConfig.enabled && traceConfig.logDebugRequests) {
+      logTraceEvent("WARN", "debug-http", "Durch Allowlist blockiert", {
+        peerIp,
+        forwardedFor: extractDebugClientIp(req),
+        url: sanitizeRequestUrlForTrace(req.url || "/")
+      });
+    }
+    jsonResponse(res, 403, { error: "Forbidden", reason: "Client-IP nicht in Allowlist", clientIp: peerIp });
+    return;
+  }
+
  if (!checkAuth(req)) {
    if (traceConfig.enabled && traceConfig.logDebugRequests) {
      logTraceEvent("WARN", "debug-http", "Unauthorized request", {
@ -596,6 +712,25 @@ function handleRequest(req: http.IncomingMessage, res: http.ServerResponse): voi
    return;
  }

+  if (pathname === "/logs/conversion") {
+    const count = normalizeLinesParam(url.searchParams.get("lines"), 100);
+    const grep = url.searchParams.get("grep") || "";
+    const logPath = getConversionLogPath();
+    const lines = logPath ? filterLines(readLogTailFromFile(logPath, count), grep) : [];
+    jsonResponse(res, 200, {
+      path: logPath,
+      available: Boolean(logPath),
+      lines,
+      count: lines.length
+    });
+    return;
+  }
+
+  if (pathname === "/providers") {
+    jsonResponse(res, 200, getProviderRuntimeSnapshot());
+    return;
+  }
+
  if (pathname === "/trace/config") {
    const patch: Record<string, unknown> = {};
    const enabled = toBooleanQuery(url.searchParams.get("enable"));
@ -881,6 +1016,7 @@ function handleRequest(req: http.IncomingMessage, res: http.ServerResponse): voi
      settings: buildRedactedSettingsPayload(readSupportSettings()),
      stats: buildStatsPayload(snapshot),
      accounts: buildAccountSummary(readSupportSettings()),
+      providers: getProviderRuntimeSnapshot(),
      history: {
        total: readSupportHistory().length,
        recent: readSupportHistory()
@ -912,6 +1048,10 @@ function handleRequest(req: http.IncomingMessage, res: http.ServerResponse): voi
          path: sessionLogPath,
          lines: filterLines(readLogTailFromFile(sessionLogPath, lineCount), grep)
        },
+        conversion: {
+          path: getConversionLogPath(),
+          lines: getConversionLogPath() ? filterLines(readLogTailFromFile(getConversionLogPath() as string, lineCount), grep) : []
+        },
        package: selectedPackage ? {
          path: packageLogPath,
          lines: filterLines(readLogTailFromFile(packageLogPath, lineCount), grep)
@ -927,32 +1067,126 @@ function handleRequest(req: http.IncomingMessage, res: http.ServerResponse): voi
  });
 }

-export function startDebugServer(mgr: DownloadManager, baseDir: string): void {
-  runtimeBaseDir = baseDir;
-  authToken = loadToken(baseDir);
-  bindPort = getPort(baseDir);
-  bindHost = getHost(baseDir);
-  writeAiManifest(baseDir);
+function openServerSocket(): Promise<void> {
+  return new Promise((resolve) => {
+    authToken = loadToken(runtimeBaseDir);
+    bindPort = getPort(runtimeBaseDir);
+    bindHost = getHost(runtimeBaseDir);
+    allowlist = loadAllowlist(runtimeBaseDir);
+    writeAiManifest(runtimeBaseDir);
    if (!authToken) {
      logger.info("Debug-Server: Kein Token in debug_token.txt, Server wird nicht gestartet");
+      resolve();
      return;
    }
-
-  manager = mgr;
-
-  server = http.createServer(handleRequest);
-  server.listen(bindPort, bindHost, () => {
-    logger.info(`Debug-Server gestartet auf ${bindHost}:${bindPort}`);
-  });
-  server.on("error", (err) => {
+    if (bindHost === "0.0.0.0" && allowlist.length === 0) {
+      logger.warn("Debug-Server: Netzwerk-Bind ohne Allowlist - nur Loopback-Clients werden akzeptiert (fail-closed)");
+    }
+    const srv = http.createServer(handleRequest);
+    let settled = false;
+    const settle = (): void => {
+      if (!settled) {
+        settled = true;
+        resolve();
+      }
+    };
+    srv.on("error", (err: NodeJS.ErrnoException) => {
+      if (err.code === "EADDRINUSE") {
+        logger.warn(`Debug-Server: Port ${bindPort} belegt (EADDRINUSE) - Server nicht gestartet`);
+      } else {
        logger.warn(`Debug-Server Fehler: ${String(err)}`);
+      }
+      if (server === srv) {
        server = null;
+      }
+      settle();
    });
+    srv.listen(bindPort, bindHost, () => {
+      logger.info(`Debug-Server gestartet auf ${bindHost}:${bindPort} (Allowlist: ${allowlist.length})`);
+      settle();
+    });
+    server = srv;
+  });
+}
+
+export function startDebugServer(mgr: DownloadManager, baseDir: string): void {
+  runtimeBaseDir = baseDir;
+  manager = mgr;
+  void openServerSocket();
+}
+
+export async function restartDebugServer(): Promise<DebugServerRuntimeStatus> {
+  const old = server;
+  if (old) {
+    server = null;
+    await new Promise<void>((resolve) => {
+      let settled = false;
+      const done = (): void => {
+        if (!settled) {
+          settled = true;
+          resolve();
+        }
+      };
+      old.close(() => done());
+      try {
+        old.closeAllConnections?.();
+      } catch {
+      }
+      setTimeout(done, 1500);
+    });
+  }
+  await openServerSocket();
+  return getDebugServerRuntimeStatus();
+}
+
+export function getDebugServerRuntimeStatus(): DebugServerRuntimeStatus {
+  return {
+    running: Boolean(server && server.listening),
+    host: bindHost,
+    port: bindPort,
+    hasToken: Boolean(authToken),
+    localOnly: isLoopbackIp(bindHost) || bindHost === "127.0.0.1",
+    allowlistCount: allowlist.length
+  };
+}
+
+export function getActiveDebugToken(): string {
+  return authToken || loadToken(runtimeBaseDir);
+}
+
+export function getDebugAllowlist(): string[] {
+  return [...allowlist];
+}
+
+export function writeDebugServerConfig(opts: { host?: string; port?: number; allowlist?: string[] }): void {
+  if (opts.host !== undefined) {
+    fs.writeFileSync(path.join(runtimeBaseDir, "debug_host.txt"), `${opts.host}\n`, "utf8");
+  }
+  if (opts.port !== undefined) {
+    fs.writeFileSync(path.join(runtimeBaseDir, "debug_port.txt"), `${opts.port}\n`, "utf8");
+  }
+  if (opts.allowlist !== undefined) {
+    const body = opts.allowlist.length > 0 ? opts.allowlist.join("\n") + "\n" : "";
+    fs.writeFileSync(getAllowlistPath(), body, "utf8");
+  }
+}
+
+export function clearDebugToken(): void {
+  try {
+    fs.unlinkSync(getDebugTokenPath());
+  } catch {
+  }
+  authToken = "";
+  writeAiManifest(runtimeBaseDir);
 }

 export function stopDebugServer(): void {
  if (server) {
    server.close();
+    try {
+      server.closeAllConnections?.();
+    } catch {
+    }
    server = null;
    logger.info("Debug-Server gestoppt");
  }
--- a/src/main/download-manager.ts
+++ b/src/main/download-manager.ts
@ -52,7 +52,7 @@ function releaseTlsSkip(): void {
 }
 import { cleanupCancelledPackageArtifactsAsync, removeDownloadLinkArtifacts, removeSampleArtifacts } from "./cleanup";
 import { planDownloadCompletion, reconcileFinalizedSize, validateDownloadedFileCompletion } from "./download-completion";
-import { AllDebridWebUnrestrictor, BestDebridWebUnrestrictor, DebridService, MegaWebUnrestrictor, RealDebridWebUnrestrictor, checkRapidgatorOnline, fetchAllDebridHostInfo, getAvailableDebridLinkApiKeys, getAvailableMegaDebridAccounts, getMegaDebridAccountCooldownState, pruneExpiredDebridLinkRuntimeState, pruneExpiredMegaDebridRuntimeState } from "./debrid";
+import { AllDebridWebUnrestrictor, BestDebridWebUnrestrictor, DebridService, MegaWebUnrestrictor, RealDebridWebUnrestrictor, checkRapidgatorOnline, fetchAllDebridHostInfo, getAvailableDebridLinkApiKeys, getAvailableMegaDebridAccounts, getMegaDebridAccountCooldownState, getMegaDebridInFlightCountForMode, pruneExpiredDebridLinkRuntimeState, pruneExpiredMegaDebridRuntimeState } from "./debrid";
 import { cleanupArchives, clearExtractResumeState, collectArchiveCleanupTargets, detectArchiveSignature, extractPackageArchives, findArchiveCandidates, hasAnyFilesRecursive, removeEmptyDirectoryTree, resetExtractorCachesForPasswordChange, type ExtractArchiveFailureInfo } from "./extractor";
 import { validateFileAgainstManifest } from "./integrity";
 import { classifyDiskError } from "./fs-error";
@ -131,6 +131,17 @@ const ARCHIVE_SETTLE_MAX_WAIT_MS = 5000;

 const MAX_SAME_DIRECT_URL_ATTEMPTS = 3;

+const MAX_HTTP416_FRESH_RESTARTS = 2;
+const HTTP416_FRESH_RESTART_DELAY_MS = 8000;
+
+function getHttp416FreshRestartDelayMs(): number {
+  const fromEnv = Number(process.env.RD_HTTP416_FRESH_RESTART_DELAY_MS ?? NaN);
+  if (Number.isFinite(fromEnv) && fromEnv >= 0 && fromEnv <= 600000) {
+    return Math.floor(fromEnv);
+  }
+  return HTTP416_FRESH_RESTART_DELAY_MS;
+}
+
 const RESUME_REWIND_BYTES = 256 * 1024;

 const REALDEBRID_TOTAL_MISMATCH_TOLERANCE_BYTES = 64 * 1024;
@ -363,6 +374,7 @@ type DownloadManagerOptions = {
  bestDebridWebUnrestrict?: BestDebridWebUnrestrictor;
  invalidateMegaSession?: () => void;
  onHistoryEntry?: HistoryEntryCallback;
+  protectEmptyClobber?: boolean;
 };

 function generateHistoryId(): string {
@ -659,6 +671,20 @@ export function parseMegaDebridCooldownRetry(errorText: string): { delayMs: numb
  return { delayMs, detail: text.replace(/mega_debrid_cooldown:\d+:/i, "").trim() };
 }

+export function parseMegaDebridSlowLinkRetry(errorText: string): { delayMs: number; detail: string } | null {
+  const text = String(errorText || "");
+  const match = text.match(/mega_debrid_slow_link:(\d+)/i);
+  if (!match) {
+    return null;
+  }
+  const raw = Number(match[1]);
+  if (!Number.isFinite(raw) || raw <= 0) {
+    return null;
+  }
+  const delayMs = Math.max(1000, Math.min(15 * 60 * 1000, raw));
+  return { delayMs, detail: text.replace(/mega_debrid_slow_link:\d+:/i, "").trim() };
+}
+
 export function parseMegaDebridResetPark(errorText: string): { delayMs: number; detail: string } | null {
  const match = String(errorText || "").match(/mega_debrid_reset_park:(\d+):(.*)$/is);
  if (!match) {
@ -1688,6 +1714,10 @@ export class DownloadManager extends EventEmitter {

  public blockAllPersistence = false;

+  private protectAgainstEmptyClobber = false;
+
+  private emptyClobberProtectionLogged = false;
+
  private debridService: DebridService;

  private invalidateMegaSessionFn?: () => void;
@ -1810,6 +1840,8 @@ export class DownloadManager extends EventEmitter {
    unrestrictRetries: number;
  }>();

+  private http416FreshRestartByItem = new Map<string, number>();
+
  private providerFailures = new Map<string, { count: number; lastFailAt: number; cooldownUntil: number }>();

  private allDebridHostInfoCache = new Map<string, { info: AllDebridHostInfo; cachedAt: number }>();
@ -1831,6 +1863,10 @@ export class DownloadManager extends EventEmitter {
    this.session = session;
    this.itemCount = Object.keys(this.session.items).length;
    this.storagePaths = storagePaths;
+    this.protectAgainstEmptyClobber = Boolean(options.protectEmptyClobber);
+    if (this.protectAgainstEmptyClobber) {
+      logger.warn("Session-Schutz aktiv: Start mit unlesbarer Session — leere Speicherungen blockiert, bis echte Daten vorliegen");
+    }
    this.debridService = new DebridService(settings, {
      megaWebUnrestrict: options.megaWebUnrestrict,
      allDebridWebUnrestrict: options.allDebridWebUnrestrict,
@ -2988,6 +3024,14 @@ export class DownloadManager extends EventEmitter {
        continue;
      }

+      const hasOwnCompletedOutput = pkg.itemIds.some((itemId) => {
+        const item = this.session.items[itemId];
+        return Boolean(item && item.status === "completed");
+      });
+      if (hasOwnCompletedOutput) {
+        continue;
+      }
+
      if (!this.isPackageSpecificExtractDir(pkg)) {
        continue;
      }
@ -5539,7 +5583,7 @@ export class DownloadManager extends EventEmitter {
    });
  }

-  public async start(): Promise<void> {
+  public async start(options?: { excludePackageIds?: ReadonlySet<string> }): Promise<void> {
    if (this.session.running) {
      return;
    }
@ -5580,6 +5624,9 @@ export class DownloadManager extends EventEmitter {
        if (item.status !== "queued" && item.status !== "reconnect_wait") {
          return false;
        }
+        if (options?.excludePackageIds?.has(item.packageId)) {
+          return false;
+        }
        const pkg = this.session.packages[item.packageId];
        return Boolean(pkg && !pkg.cancelled && pkg.enabled);
      });
@ -5644,9 +5691,15 @@ export class DownloadManager extends EventEmitter {
    this.providerStartReservations.clear();
    this.pacedStartReservationByItem.clear();
    this.retryStateByItem.clear();
+    this.http416FreshRestartByItem.clear();
    this.itemContributedBytes.clear();
    this.reservedTargetPaths.clear();
    this.claimedTargetPathByItem.clear();
+    if (options?.excludePackageIds) {
+      for (const excluded of options.excludePackageIds) {
+        this.runPackageIds.delete(excluded);
+      }
+    }

    this.session.running = true;
    this.session.paused = false;
@ -5821,7 +5874,9 @@ export class DownloadManager extends EventEmitter {
      const itemCount = Object.keys(this.session.items).length;
      logger.info(`Shutdown-Save: ${pkgCount} Pakete, ${itemCount} Items`);
      this.foldRuntimeIntoSettings(nowMs());
+      if (!this.guardBlocksSessionSave()) {
        saveSession(this.storagePaths, this.session);
+      }
      saveSettings(this.storagePaths, this.settings);
    } else {
      logger.info(`Shutdown-Save übersprungen: skipShutdownPersist=${this.skipShutdownPersist}, blockAllPersistence=${this.blockAllPersistence}`);
@ -6124,10 +6179,29 @@ export class DownloadManager extends EventEmitter {
    }, delay);
  }

+  private guardBlocksSessionSave(): boolean {
+    if (!this.protectAgainstEmptyClobber) {
+      return false;
+    }
+    const isEmpty = Object.keys(this.session.packages).length === 0 && Object.keys(this.session.items).length === 0;
+    if (isEmpty) {
+      if (!this.emptyClobberProtectionLogged) {
+        logger.warn("Leere Session-Speicherung uebersprungen (Schutz nach unlesbarem Start) — vorhandene Datei bleibt unangetastet");
+        this.emptyClobberProtectionLogged = true;
+      }
+      return true;
+    }
+    this.protectAgainstEmptyClobber = false;
+    logger.info("Session-Schutz aufgehoben: nicht-leere Session wird wieder normal gespeichert");
+    return false;
+  }
+
  private persistNow(): void {
    const now = nowMs();
    this.lastPersistAt = now;
+    if (!this.guardBlocksSessionSave()) {
      void saveSessionAsync(this.storagePaths, this.session).catch((err) => logger.warn(`saveSessionAsync Fehler: ${compactErrorText(err)}`));
+    }
    if (now - this.lastSettingsPersistAt >= 30000) {
      this.foldRuntimeIntoSettings(now);
      this.lastSettingsPersistAt = now;
@ -6141,7 +6215,9 @@ export class DownloadManager extends EventEmitter {
    const itemCount = Object.keys(this.session.items).length;
    logger.info(`Pre-Update Sync-Save: ${pkgCount} Pakete, ${itemCount} Items`);
    this.foldRuntimeIntoSettings(nowMs());
+    if (!this.guardBlocksSessionSave()) {
      saveSession(this.storagePaths, this.session);
+    }
    saveSettings(this.storagePaths, this.settings);
  }

@ -8150,7 +8226,13 @@ export class DownloadManager extends EventEmitter {
    const provider = resolveMegaDebridProvider(this.settings, this.getExpectedProviderForItem(item));
    const serializedValidatingLimit = this.getSerializedValidatingLimit(provider);
    if (provider && Number.isFinite(serializedValidatingLimit) && serializedValidatingLimit < Number.MAX_SAFE_INTEGER) {
-      return this.getProviderValidatingTaskCount(provider, item.id) >= serializedValidatingLimit;
+      const validating = this.getProviderValidatingTaskCount(provider, item.id);
+      if (provider === "megadebrid-api") {
+        const webInFlight = getMegaDebridInFlightCountForMode("web");
+        const overlapAllowance = Math.min(serializedValidatingLimit, webInFlight);
+        return validating >= serializedValidatingLimit + overlapAllowance;
+      }
+      return validating >= serializedValidatingLimit;
    }
    if (provider !== "alldebrid") {
      return false;
@ -8659,6 +8741,53 @@ export class DownloadManager extends EventEmitter {
    this.queueRetry(item, active, delayMs, `HTTP 416 erkannt, Retry ${active.genericErrorRetries}/${retryDisplayLimit}`);
  }

+  private escalateHttp416OrFail(item: DownloadItem, active: ActiveTask, claimedTargetPath: string, errorText: string): void {
+    const freshRestarts = this.http416FreshRestartByItem.get(item.id) || 0;
+    if (freshRestarts < MAX_HTTP416_FRESH_RESTARTS) {
+      this.http416FreshRestartByItem.set(item.id, freshRestarts + 1);
+      const resetTargetPath = claimedTargetPath || String(item.targetPath || "").trim();
+      if (resetTargetPath) {
+        try {
+          fs.rmSync(resetTargetPath, { force: true });
+        } catch {
+        }
+      }
+      this.releaseTargetPath(item.id);
+      this.dropItemContribution(item.id);
+      item.retries += 1;
+      item.downloadedBytes = 0;
+      item.totalBytes = null;
+      item.progressPercent = 0;
+      item.speedBps = 0;
+      item.lastError = "";
+      active.genericErrorRetries = 0;
+      active.freshRetryUsed = false;
+      active.resumeHardResetUsed = false;
+      logger.warn(
+        `HTTP 416 Budget erschöpft: item=${item.fileName || item.id}, ` +
+        `kompletter Neu-Download ${freshRestarts + 1}/${MAX_HTTP416_FRESH_RESTARTS} (Partial verworfen, kein Resume), provider=${item.provider || "?"}`
+      );
+      this.queueRetry(item, active, getHttp416FreshRestartDelayMs(), `Range-Konflikt (HTTP 416): Neu-Download ${freshRestarts + 1}/${MAX_HTTP416_FRESH_RESTARTS}`);
+      this.persistSoon();
+      this.emitState();
+      return;
+    }
+    this.http416FreshRestartByItem.delete(item.id);
+    item.status = "failed";
+    this.recordRunOutcome(item.id, "failed");
+    item.lastError = errorText;
+    item.fullStatus = `Fehler: ${item.lastError}`;
+    item.speedBps = 0;
+    item.updatedAt = nowMs();
+    const failPkg = this.session.packages[item.packageId];
+    if (failPkg) {
+      this.refreshPackageStatus(failPkg);
+    }
+    this.persistSoon();
+    this.emitState();
+    this.retryStateByItem.delete(item.id);
+  }
+
  private startItem(packageId: string, itemId: string): void {
    const item = this.session.items[itemId];
    const pkg = this.session.packages[packageId];
@ -9249,12 +9378,16 @@ export class DownloadManager extends EventEmitter {
                return;
              }
            }
-            if (isHttp416Text(exhaustedReason) && active.genericErrorRetries < maxHttp416Retries) {
+            if (isHttp416Text(exhaustedReason)) {
+              if (active.genericErrorRetries < maxHttp416Retries) {
                this.scheduleHttp416Retry(item, active, retryDisplayLimit, exhaustedReason, claimedTargetPath);
                this.persistSoon();
                this.emitState();
                return;
              }
+              this.escalateHttp416OrFail(item, active, claimedTargetPath, exhaustedReason);
+              return;
+            }
            if (isResumeHardResetReason(exhaustedReason) && !active.resumeHardResetUsed) {
              active.resumeHardResetUsed = true;
              item.retries += 1;
@ -9309,17 +9442,7 @@ export class DownloadManager extends EventEmitter {
              this.emitState();
              return;
            }
-            item.status = "failed";
-            this.recordRunOutcome(item.id, "failed");
-            item.lastError = errorText;
-            item.fullStatus = `Fehler: ${item.lastError}`;
-            item.speedBps = 0;
-            item.updatedAt = nowMs();
-            const failPkg416 = this.session.packages[item.packageId];
-            if (failPkg416) this.refreshPackageStatus(failPkg416);
-            this.persistSoon();
-            this.emitState();
-            this.retryStateByItem.delete(item.id);
+            this.escalateHttp416OrFail(item, active, claimedTargetPath, errorText);
            return;
          }
          if (shouldFreshRetry) {
@ -9435,6 +9558,24 @@ export class DownloadManager extends EventEmitter {
          }

          const megaRawError = error instanceof Error ? String(error.message || "") : String(error || "");
+          const megaSlowLinkRetry = parseMegaDebridSlowLinkRetry(megaRawError);
+          if (megaSlowLinkRetry && active.unrestrictRetries < maxUnrestrictRetries) {
+            active.unrestrictRetries += 1;
+            item.retries += 1;
+            item.provider = null;
+            logger.warn(`Mega-Debrid Link langsam (Timeout): item=${item.fileName || item.id}, retry=${active.unrestrictRetries}/${retryDisplayLimit}, delay=${megaSlowLinkRetry.delayMs}ms, link=${item.url.slice(0, 80)}`);
+            this.queueRetry(
+              item,
+              active,
+              megaSlowLinkRetry.delayMs,
+              `Mega-Debrid: Link zu langsam, Einzel-Retry in ${Math.ceil(megaSlowLinkRetry.delayMs / 1000)}s`
+            );
+            item.lastError = megaSlowLinkRetry.detail || errorText;
+            this.persistSoon();
+            this.emitState();
+            return;
+          }
+
          const megaCooldownRetry = parseMegaDebridCooldownRetry(megaRawError);
          if (megaCooldownRetry && active.unrestrictRetries < maxUnrestrictRetries) {
            active.unrestrictRetries += 1;
--- a/src/main/main.ts
+++ b/src/main/main.ts
@ -1,7 +1,7 @@
 import fs from "node:fs";
 import path from "node:path";
 import { app, BrowserWindow, clipboard, dialog, ipcMain, IpcMainInvokeEvent, Menu, shell, Tray } from "electron";
-import { AddLinksPayload, AppSettings, DebridProvider, UpdateInstallProgress } from "../shared/types";
+import { AddLinksPayload, AppSettings, DebridProvider, EnableRemoteDiagnosticsInput, UpdateInstallProgress } from "../shared/types";
 import { AppController } from "./app-controller";
 import { IPC_CHANNELS } from "../shared/ipc";
 import { getLogFilePath, logger } from "./logger";
@ -571,7 +571,7 @@ function registerIpcHandlers(): void {

  ipcMain.handle(IPC_CHANNELS.EXPORT_BACKUP, async () => {
    const options = {
-      defaultPath: `mdd-backup-${new Date().toISOString().slice(0, 10)}.mdd`,
+      defaultPath: `${new Date().toISOString().slice(0, 10).split("-").reverse().join("-")}-mdd-backup.mdd`,
      filters: [{ name: "MDD Backup", extensions: ["mdd"] }]
    };
    const result = mainWindow ? await dialog.showSaveDialog(mainWindow, options) : await dialog.showSaveDialog(options);
@ -671,6 +671,33 @@ function registerIpcHandlers(): void {
    return { path: rotated.path };
  });

+  ipcMain.handle(IPC_CHANNELS.GET_REMOTE_DIAGNOSTICS, async () => {
+    return controller.getRemoteDiagnostics();
+  });
+
+  ipcMain.handle(IPC_CHANNELS.ENABLE_REMOTE_DIAGNOSTICS, async (_event: IpcMainInvokeEvent, input: EnableRemoteDiagnosticsInput) => {
+    if (!input || (input.hostMode !== "local" && input.hostMode !== "network")) {
+      throw new Error("hostMode muss 'local' oder 'network' sein");
+    }
+    const allowlist = Array.isArray(input.allowlist) ? input.allowlist.map((entry) => String(entry)) : [];
+    return controller.enableRemoteDiagnostics({
+      hostMode: input.hostMode,
+      publicHost: String(input.publicHost || ""),
+      port: input.port ? Number(input.port) : undefined,
+      allowlist,
+      name: input.name ? String(input.name) : undefined,
+      rotateToken: Boolean(input.rotateToken)
+    });
+  });
+
+  ipcMain.handle(IPC_CHANNELS.DISABLE_REMOTE_DIAGNOSTICS, async () => {
+    return controller.disableRemoteDiagnostics();
+  });
+
+  ipcMain.handle(IPC_CHANNELS.ROTATE_REMOTE_DIAGNOSTICS_TOKEN, async () => {
+    return controller.rotateRemoteDiagnosticsToken();
+  });
+
  ipcMain.handle(IPC_CHANNELS.OPEN_ITEM_LOG, async (_event: IpcMainInvokeEvent, itemId: string) => {
    validateString(itemId, "itemId");
    const logPath = controller.getItemLogPath(itemId);
--- a/src/main/storage.ts
+++ b/src/main/storage.ts
@ -461,6 +461,7 @@ export function normalizeSettings(settings: AppSettings): AppSettings {
    hideExtractedItems: settings.hideExtractedItems !== undefined ? Boolean(settings.hideExtractedItems) : defaults.hideExtractedItems,
    confirmDeleteSelection: settings.confirmDeleteSelection !== undefined ? Boolean(settings.confirmDeleteSelection) : defaults.confirmDeleteSelection,
    backupIncludeDownloads: settings.backupIncludeDownloads !== undefined ? Boolean(settings.backupIncludeDownloads) : defaults.backupIncludeDownloads,
+    backupIncludeMcp: settings.backupIncludeMcp !== undefined ? Boolean(settings.backupIncludeMcp) : defaults.backupIncludeMcp,
    notifyUrl: asText(settings.notifyUrl) || defaults.notifyUrl,
    notifyMention: asText(settings.notifyMention) || defaults.notifyMention,
    notifyOnPackageCompleted: settings.notifyOnPackageCompleted !== undefined ? Boolean(settings.notifyOnPackageCompleted) : defaults.notifyOnPackageCompleted,
@ -889,21 +890,50 @@ export function normalizeLoadedSessionTransientFields(session: SessionState): Se
  return session;
 }

+const TRANSIENT_READ_CODES = new Set(["EBUSY", "EPERM", "EAGAIN"]);
+
+function sleepSyncMs(ms: number): void {
+  if (ms <= 0) {
+    return;
+  }
+  Atomics.wait(new Int32Array(new SharedArrayBuffer(4)), 0, 0, ms);
+}
+
 function readSessionFile(filePath: string): SessionState | null {
+  let raw: string | null = null;
+  const maxAttempts = 5;
+  for (let attempt = 1; attempt <= maxAttempts; attempt += 1) {
    try {
-    const parsed = JSON.parse(fs.readFileSync(filePath, "utf8")) as unknown;
+      raw = fs.readFileSync(filePath, "utf8");
+      break;
+    } catch (error) {
+      const code = (error as NodeJS.ErrnoException)?.code || "";
+      if (TRANSIENT_READ_CODES.has(code) && attempt < maxAttempts) {
+        const backoffMs = 100 * 2 ** (attempt - 1);
+        logger.warn(`Session-Datei vorübergehend gesperrt (${code}), Versuch ${attempt}/${maxAttempts}, warte ${backoffMs}ms: ${filePath}`);
+        sleepSyncMs(backoffMs);
+        continue;
+      }
+      if (code === "EACCES" || code === "EPERM") {
+        logger.error(`Session-Datei nicht zugreifbar (${code}): ${filePath} - pruefe Datei-/Ordner-Berechtigungen fuer Benutzer ${process.env.USERNAME || process.env.USER || "?"}`);
+      } else {
+        logger.error(`Session-Datei nicht lesbar (${code || "?"}): ${filePath}: ${String(error)}`);
+      }
+      return null;
+    }
+  }
+  if (raw === null) {
+    return null;
+  }
+  try {
+    const parsed = JSON.parse(raw) as unknown;
    const session = normalizeLoadedSessionTransientFields(normalizeLoadedSession(parsed));
    const pkgCount = Object.keys(session.packages).length;
    const itemCount = Object.keys(session.items).length;
    logger.info(`Session geladen: ${filePath} (${pkgCount} Pakete, ${itemCount} Items)`);
    return session;
  } catch (error) {
-    const code = (error as NodeJS.ErrnoException)?.code || "";
-    if (code === "EACCES" || code === "EPERM") {
-      logger.error(`Session-Datei nicht zugreifbar (${code}): ${filePath} - pruefe Datei-/Ordner-Berechtigungen fuer Benutzer ${process.env.USERNAME || process.env.USER || "?"}`);
-    } else {
-      logger.error(`Session-Datei nicht lesbar: ${filePath}: ${String(error)}`);
-    }
+    logger.error(`Session-Datei beschädigt (JSON ungültig): ${filePath}: ${String(error)}`);
    return null;
  }
 }
@ -1003,17 +1033,31 @@ export function emptySession(): SessionState {
  };
 }

-export function loadSession(paths: StoragePaths): SessionState {
+export type SessionLoadStatus =
+  | "ok"
+  | "recovered-backup"
+  | "recovered-temp"
+  | "empty-fresh"
+  | "empty-unreadable";
+
+export interface SessionLoadResult {
+  session: SessionState;
+  status: SessionLoadStatus;
+}
+
+export function loadSessionWithStatus(paths: StoragePaths): SessionLoadResult {
  ensureBaseDir(paths.baseDir);
  const backupFile = sessionBackupPath(paths.sessionFile);
+  const syncTempFile = sessionTempPath(paths.sessionFile, "sync");
+  const asyncTempFile = sessionTempPath(paths.sessionFile, "async");
  const primaryExists = fs.existsSync(paths.sessionFile);
+  const backupExists = fs.existsSync(backupFile);
+  const anyTempExists = fs.existsSync(syncTempFile) || fs.existsSync(asyncTempFile);
+
  if (!primaryExists) {
-    const hasRecoverable = fs.existsSync(backupFile)
-      || fs.existsSync(sessionTempPath(paths.sessionFile, "sync"))
-      || fs.existsSync(sessionTempPath(paths.sessionFile, "async"));
-    if (!hasRecoverable) {
+    if (!backupExists && !anyTempExists) {
      logger.info("Keine Session-Datei vorhanden, starte mit leerer Session");
-      return emptySession();
+      return { session: emptySession(), status: "empty-fresh" };
    }
    logger.warn("Session-Primaerdatei fehlt, aber Backup/Temp vorhanden — Wiederherstellung wird versucht");
  }
@ -1022,7 +1066,7 @@ export function loadSession(paths: StoragePaths): SessionState {

  if (primary) {
    const primaryPkgCount = Object.keys(primary.packages).length;
-    if (primaryPkgCount === 0 && fs.existsSync(backupFile)) {
+    if (primaryPkgCount === 0 && backupExists) {
      const backup = readSessionFile(backupFile);
      if (backup) {
        const backupPkgCount = Object.keys(backup.packages).length;
@ -1030,29 +1074,27 @@ export function loadSession(paths: StoragePaths): SessionState {
          logger.warn(`Session-Datei ist leer (0 Pakete), aber Backup hat ${backupPkgCount} Pakete — verwende Backup`);
          try {
            const payload = JSON.stringify({ ...backup, updatedAt: Date.now() }, safeJsonReplacer);
-            const tempPath = sessionTempPath(paths.sessionFile, "sync");
-            fs.writeFileSync(tempPath, payload, "utf8");
-            syncRenameWithExdevFallback(tempPath, paths.sessionFile);
+            fs.writeFileSync(syncTempFile, payload, "utf8");
+            syncRenameWithExdevFallback(syncTempFile, paths.sessionFile);
          } catch {
          }
-          return backup;
+          return { session: backup, status: "recovered-backup" };
        }
      }
    }
-    return primary;
+    return { session: primary, status: "ok" };
  }

-  const backup = fs.existsSync(backupFile) ? readSessionFile(backupFile) : null;
+  const backup = backupExists ? readSessionFile(backupFile) : null;
  if (backup) {
    logger.warn("Session defekt, Backup-Datei wird verwendet");
    try {
      const payload = JSON.stringify({ ...backup, updatedAt: Date.now() }, safeJsonReplacer);
-      const tempPath = sessionTempPath(paths.sessionFile, "sync");
-      fs.writeFileSync(tempPath, payload, "utf8");
-      syncRenameWithExdevFallback(tempPath, paths.sessionFile);
+      fs.writeFileSync(syncTempFile, payload, "utf8");
+      syncRenameWithExdevFallback(syncTempFile, paths.sessionFile);
    } catch {
    }
-    return backup;
+    return { session: backup, status: "recovered-backup" };
  }

  for (const kind of ["sync", "async"] as const) {
@ -1066,13 +1108,21 @@ export function loadSession(paths: StoragePaths): SessionState {
          fs.writeFileSync(paths.sessionFile, payload, "utf8");
        } catch {
        }
-        return tmpSession;
+        return { session: tmpSession, status: "recovered-temp" };
      }
    }
  }

-  logger.error("Session konnte nicht geladen werden (Primary, Backup und Temp-Dateien fehlgeschlagen)");
-  return emptySession();
+  if (primaryExists || backupExists || anyTempExists) {
+    logger.error("Session konnte nicht geladen werden (Primary, Backup und Temp-Dateien fehlgeschlagen) — Schutz gegen leeres Ueberschreiben aktiv");
+    return { session: emptySession(), status: "empty-unreadable" };
+  }
+
+  return { session: emptySession(), status: "empty-fresh" };
+}
+
+export function loadSession(paths: StoragePaths): SessionState {
+  return loadSessionWithStatus(paths).session;
 }

 export function saveSession(paths: StoragePaths, session: SessionState): void {
@ -1087,7 +1137,13 @@ export function saveSession(paths: StoragePaths, session: SessionState): void {
  const payload = JSON.stringify({ ...session, updatedAt: Date.now() }, safeJsonReplacer);
  const tempPath = sessionTempPath(paths.sessionFile, "sync");
  try {
-    fs.writeFileSync(tempPath, payload, "utf8");
+    const fd = fs.openSync(tempPath, "w");
+    try {
+      fs.writeSync(fd, payload);
+      fs.fsyncSync(fd);
+    } finally {
+      fs.closeSync(fd);
+    }
    syncRenameWithExdevFallback(tempPath, paths.sessionFile);
  } catch (error) {
    try { fs.rmSync(tempPath, { force: true }); } catch {  }
@ -1103,7 +1159,13 @@ async function writeSessionPayload(paths: StoragePaths, payload: string, generat
  await fs.promises.mkdir(paths.baseDir, { recursive: true });
  await fsp.copyFile(paths.sessionFile, sessionBackupPath(paths.sessionFile)).catch(() => {});
  const tempPath = sessionTempPath(paths.sessionFile, "async");
-  await fsp.writeFile(tempPath, payload, "utf8");
+  const handle = await fsp.open(tempPath, "w");
+  try {
+    await handle.writeFile(payload, "utf8");
+    await handle.sync();
+  } finally {
+    await handle.close();
+  }
  if (generation < syncSaveGeneration) {
    await fsp.rm(tempPath, { force: true }).catch(() => {});
    return;
--- a/src/preload/preload.ts
+++ b/src/preload/preload.ts
@ -7,8 +7,10 @@ import {
  DebridLinkHostLimitInfo,
  DebridProvider,
  DuplicatePolicy,
+  EnableRemoteDiagnosticsInput,
  HistoryEntry,
  PackagePriority,
+  RemoteDiagnosticsInfo,
  RendererErrorReport,
  SessionStats,
  StartConflictEntry,
@ -74,6 +76,10 @@ const api: ElectronApi = {
  getTraceConfig: () => ipcRenderer.invoke(IPC_CHANNELS.GET_TRACE_CONFIG),
  setTraceEnabled: (enabled: boolean, note?: string, durationMinutes?: number) => ipcRenderer.invoke(IPC_CHANNELS.SET_TRACE_ENABLED, enabled, note, durationMinutes),
  rotateDebugToken: (): Promise<{ path: string }> => ipcRenderer.invoke(IPC_CHANNELS.ROTATE_DEBUG_TOKEN),
+  getRemoteDiagnostics: (): Promise<RemoteDiagnosticsInfo> => ipcRenderer.invoke(IPC_CHANNELS.GET_REMOTE_DIAGNOSTICS),
+  enableRemoteDiagnostics: (input: EnableRemoteDiagnosticsInput): Promise<RemoteDiagnosticsInfo> => ipcRenderer.invoke(IPC_CHANNELS.ENABLE_REMOTE_DIAGNOSTICS, input),
+  disableRemoteDiagnostics: (): Promise<RemoteDiagnosticsInfo> => ipcRenderer.invoke(IPC_CHANNELS.DISABLE_REMOTE_DIAGNOSTICS),
+  rotateRemoteDiagnosticsToken: (): Promise<RemoteDiagnosticsInfo> => ipcRenderer.invoke(IPC_CHANNELS.ROTATE_REMOTE_DIAGNOSTICS_TOKEN),
  openRealDebridLogin: (): Promise<void> => ipcRenderer.invoke(IPC_CHANNELS.OPEN_REALDEBRID_LOGIN),
  openAllDebridLogin: (): Promise<void> => ipcRenderer.invoke(IPC_CHANNELS.OPEN_ALLDEBRID_LOGIN),
  importBestDebridCookies: (): Promise<number> => ipcRenderer.invoke(IPC_CHANNELS.IMPORT_BESTDEBRID_COOKIES),
--- a/src/renderer/App.tsx
+++ b/src/renderer/App.tsx
@ -16,6 +16,7 @@ import type {
  DuplicatePolicy,
  HistoryEntry,
  PackageEntry,
+  RemoteDiagnosticsInfo,
  StartConflictEntry,
  UiSnapshot,
  UpdateCheckResult,
@ -855,7 +856,7 @@ const emptySnapshot = (): UiSnapshot => ({
    autoReconnect: false, reconnectWaitSeconds: 45, completedCleanupPolicy: "never",
    maxParallel: 4, maxParallelExtract: 2, extractCpuPriority: "high", retryLimit: 0, speedLimitEnabled: false, speedLimitKbps: 0, speedLimitMode: "global",
    updateRepo: "", autoUpdateCheck: true, clipboardWatch: false, minimizeToTray: false,
-    theme: "dark", collapseNewPackages: true, historyRetentionMode: "permanent", historyMaxEntries: 500, historyMaxAgeDays: 0, autoSortPackagesByProgress: true, autoSkipExtracted: false, hideExtractedItems: true, confirmDeleteSelection: true, backupIncludeDownloads: false,
+    theme: "dark", collapseNewPackages: true, historyRetentionMode: "permanent", historyMaxEntries: 500, historyMaxAgeDays: 0, autoSortPackagesByProgress: true, autoSkipExtracted: false, hideExtractedItems: true, confirmDeleteSelection: true, backupIncludeDownloads: false, backupIncludeMcp: false,
    notifyUrl: "", notifyMention: "", notifyOnPackageCompleted: false, notifyOnPackageFailed: false, notifyOnRunFinished: false,
    accountListShowDetailedDebridLinkKeys: false,
    bandwidthSchedules: [], totalDownloadedAllTime: 0, totalCompletedFilesAllTime: 0, totalRuntimeAllTimeMs: 0,
@ -1761,6 +1762,14 @@ export function App(): ReactElement {
  const [startConflictPrompt, setStartConflictPrompt] = useState<StartConflictPromptState | null>(null);
  const startConflictResolverRef = useRef<((result: { policy: Extract<DuplicatePolicy, "skip" | "overwrite">; applyToAll: boolean } | null) => void) | null>(null);
  const [confirmPrompt, setConfirmPrompt] = useState<ConfirmPromptState | null>(null);
+  const [remoteDiag, setRemoteDiag] = useState<RemoteDiagnosticsInfo | null>(null);
+  const [remoteDiagOpen, setRemoteDiagOpen] = useState(false);
+  const [remoteDiagBusy, setRemoteDiagBusy] = useState(false);
+  const [rdHostMode, setRdHostMode] = useState<"local" | "network">("local");
+  const [rdPublicHost, setRdPublicHost] = useState("");
+  const [rdPort, setRdPort] = useState("9868");
+  const [rdAllowlist, setRdAllowlist] = useState("");
+  const [rdName, setRdName] = useState("");
  const confirmResolverRef = useRef<((confirmed: boolean) => void) | null>(null);
  const confirmQueueRef = useRef<Array<{ prompt: ConfirmPromptState; resolve: (confirmed: boolean) => void }>>([]);
  const importQueueFocusHandlerRef = useRef<(() => void) | null>(null);
@ -4328,6 +4337,89 @@ export function App(): ReactElement {
    });
  };

+  const applyRemoteDiagInfo = (info: RemoteDiagnosticsInfo): void => {
+    setRemoteDiag(info);
+    setRdHostMode(info.status.localOnly ? "local" : "network");
+    setRdPublicHost(info.publicHost || (info.status.localOnly ? "" : (info.suggestedHosts[0] || "")));
+    setRdPort(String(info.status.port || 9868));
+    setRdAllowlist(info.allowlist.join("\n"));
+    setRdName(info.name || "");
+  };
+
+  const onOpenRemoteDiagnostics = async (): Promise<void> => {
+    closeMenus();
+    try {
+      const info = await window.rd.getRemoteDiagnostics();
+      applyRemoteDiagInfo(info);
+      setRemoteDiagOpen(true);
+    } catch (error) {
+      showToast(`Ferndiagnose-Status fehlgeschlagen: ${String(error)}`, 3000);
+    }
+  };
+
+  const onSubmitRemoteDiagnostics = async (): Promise<void> => {
+    const port = Number(rdPort) || 9868;
+    const allowlist = rdAllowlist.split(/\r?\n/).map((line) => line.trim()).filter((line) => line.length > 0);
+    if (rdHostMode === "network" && allowlist.length === 0) {
+      showToast("Netzwerkmodus braucht mindestens eine IP oder CIDR in der Allowlist", 3600);
+      return;
+    }
+    setRemoteDiagBusy(true);
+    try {
+      const info = await window.rd.enableRemoteDiagnostics({
+        hostMode: rdHostMode,
+        publicHost: rdPublicHost,
+        port,
+        allowlist,
+        name: rdName
+      });
+      applyRemoteDiagInfo(info);
+      showToast(info.status.running ? "Ferndiagnose aktiv" : "Ferndiagnose konfiguriert", 2600);
+    } catch (error) {
+      showToast(`Aktivieren fehlgeschlagen: ${String(error)}`, 3600);
+    } finally {
+      setRemoteDiagBusy(false);
+    }
+  };
+
+  const onDisableRemoteDiagnostics = async (): Promise<void> => {
+    setRemoteDiagBusy(true);
+    try {
+      const info = await window.rd.disableRemoteDiagnostics();
+      applyRemoteDiagInfo(info);
+      showToast("Ferndiagnose deaktiviert", 2400);
+    } catch (error) {
+      showToast(`Deaktivieren fehlgeschlagen: ${String(error)}`, 3000);
+    } finally {
+      setRemoteDiagBusy(false);
+    }
+  };
+
+  const onRotateRemoteDiagnosticsToken = async (): Promise<void> => {
+    setRemoteDiagBusy(true);
+    try {
+      const info = await window.rd.rotateRemoteDiagnosticsToken();
+      applyRemoteDiagInfo(info);
+      showToast("Neues Token - alter Verbindungscode ist ungueltig", 3000);
+    } catch (error) {
+      showToast(`Token-Rotation fehlgeschlagen: ${String(error)}`, 3000);
+    } finally {
+      setRemoteDiagBusy(false);
+    }
+  };
+
+  const onCopyRemoteDiagnosticsCode = async (): Promise<void> => {
+    if (!remoteDiag?.code) {
+      return;
+    }
+    try {
+      await navigator.clipboard.writeText(remoteDiag.code);
+      showToast("Verbindungscode kopiert", 2200);
+    } catch {
+      showToast("Kopieren fehlgeschlagen", 2200);
+    }
+  };
+
  const onMenuRestart = (): void => {
    closeMenus();
    void window.rd.restart();
@ -4718,6 +4810,7 @@ export function App(): ReactElement {
                <button className="menu-submenu-trigger">Remote-Support</button>
                {openSubmenu === "hilfe-remote" && (
                  <div className="menu-submenu-dropdown">
+                    <button className="menu-dropdown-item" onClick={() => { void onOpenRemoteDiagnostics(); }}><span>Ferndiagnose (MCP) …</span></button>
                    <button className="menu-dropdown-item" onClick={() => { void onExportSupportBundle(); }}><span>Support-Bundle exportieren</span></button>
                    <button className="menu-dropdown-item" onClick={() => { void onToggleSupportTrace(); }}><span>{supportTraceEnabled ? "Support-Trace deaktivieren" : "Support-Trace aktivieren"}</span></button>
                  </div>
@ -5349,6 +5442,8 @@ export function App(): ReactElement {
                    <div className="setting-hint">Sicherheitsabfrage vor dem Entfernen ausgewählter Einträge.</div>
                    <label className="toggle-line"><input type="checkbox" checked={settingsDraft.backupIncludeDownloads} onChange={(e) => setBool("backupIncludeDownloads", e.target.checked)} /> Download-Liste mitsichern</label>
                    <div className="setting-hint">Sicherung enthält auch die Download-Liste; Standard: nur Einstellungen.</div>
+                    <label className="toggle-line"><input type="checkbox" checked={settingsDraft.backupIncludeMcp} onChange={(e) => setBool("backupIncludeMcp", e.target.checked)} /> Ferndiagnose-Einstellungen mitsichern</label>
+                    <div className="setting-hint">Allowlist, Port und Freigabemodus (lokal/Netzwerk) reisen mit. Verbindungs-Token und eigene Adresse bleiben pro Server – nach dem Import einmal „Aktivieren" drücken.</div>
                    <label className="toggle-line"><input type="checkbox" checked={settingsDraft.theme === "light"} onChange={(e) => {
                      const next = e.target.checked ? "light" : "dark";
                      settingsDraftRevisionRef.current += 1;
@ -5934,6 +6029,97 @@ export function App(): ReactElement {
        </div>
      )}

+      {remoteDiagOpen && (
+        <div className="modal-backdrop" onClick={() => setRemoteDiagOpen(false)}>
+          <div className="modal-card" onClick={(event) => event.stopPropagation()}>
+            <h3>Ferndiagnose (MCP)</h3>
+            <p>Aktiviert einen abgesicherten Lesezugriff auf Status, Logs und Fehler dieses Servers. Den Verbindungscode dem Assistenten geben - er verbindet sich, sieht alles und behebt Probleme.</p>
+            <div className="rd-status-line">
+              <span className={`rd-dot${remoteDiag?.status.running ? " on" : ""}`} />
+              <span>
+                {remoteDiag?.status.running
+                  ? `Aktiv auf ${remoteDiag.status.host}:${remoteDiag.status.port}${remoteDiag.status.localOnly ? " (nur lokal)" : ` (Allowlist: ${remoteDiag.status.allowlistCount})`}`
+                  : "Inaktiv"}
+              </span>
+            </div>
+
+            <div className="rd-field">
+              <label>Sichtbarkeit</label>
+              <div className="rd-seg">
+                <button className={rdHostMode === "local" ? "active" : ""} onClick={() => setRdHostMode("local")}>Nur lokal</button>
+                <button className={rdHostMode === "network" ? "active" : ""} onClick={() => setRdHostMode("network")}>Im Netzwerk</button>
+              </div>
+              <span className="rd-hint">
+                {rdHostMode === "local"
+                  ? "Bindet nur an 127.0.0.1. Fernzugriff nur ueber einen Tunnel (z.B. Tailscale/SSH) - die sicherste Variante."
+                  : "Bindet an 0.0.0.0. Erreichbar im Netzwerk, erfordert eine Allowlist. Nur in vertrauenswuerdigen Netzen/VPN nutzen."}
+              </span>
+            </div>
+
+            <div className="rd-field">
+              <label>Oeffentliche Adresse (fuer den Verbindungscode)</label>
+              <input
+                value={rdPublicHost}
+                placeholder={rdHostMode === "local" ? "127.0.0.1 oder Tunnel-Adresse" : "Server-IP oder DNS-Name"}
+                onChange={(event) => setRdPublicHost(event.target.value)}
+              />
+              {remoteDiag && remoteDiag.suggestedHosts.length > 0 && (
+                <div className="rd-chips">
+                  {remoteDiag.suggestedHosts.map((host) => (
+                    <button key={host} className="rd-chip" onClick={() => setRdPublicHost(host)}>{host}</button>
+                  ))}
+                </div>
+              )}
+            </div>
+
+            <div className="rd-field rd-field-inline">
+              <div className="rd-field">
+                <label>Port</label>
+                <input value={rdPort} onChange={(event) => setRdPort(event.target.value.replace(/[^0-9]/g, ""))} />
+              </div>
+              <div className="rd-field">
+                <label>Name (optional)</label>
+                <input value={rdName} placeholder="z.B. Server-Berlin" onChange={(event) => setRdName(event.target.value)} />
+              </div>
+            </div>
+
+            {rdHostMode === "network" && (
+              <div className="rd-field">
+                <label>Allowlist - erlaubte IPs/CIDR (eine pro Zeile)</label>
+                <textarea
+                  value={rdAllowlist}
+                  placeholder={"203.0.113.5\n10.0.0.0/24"}
+                  onChange={(event) => setRdAllowlist(event.target.value)}
+                />
+                <span className="rd-hint">Pflicht im Netzwerkmodus. Nur diese Quell-IPs duerfen verbinden (zusaetzlich zum Token). Loopback ist immer erlaubt.</span>
+              </div>
+            )}
+
+            {remoteDiag?.status.running && remoteDiag.code && (
+              <div className="rd-field">
+                <label>Verbindungscode</label>
+                <div className="rd-code">{remoteDiag.code}</div>
+                <div className="rd-chips">
+                  <button className="btn" onClick={() => { void onCopyRemoteDiagnosticsCode(); }}>Kopieren</button>
+                  <button className="btn" onClick={() => { void onRotateRemoteDiagnosticsToken(); }} disabled={remoteDiagBusy}>Token neu (Code ungueltig machen)</button>
+                </div>
+                <span className="rd-hint">Enthaelt das Zugriffstoken - wie ein Passwort behandeln. Token neu = alter Code wird sofort ungueltig.</span>
+              </div>
+            )}
+
+            <div className="modal-actions">
+              <button className="btn" onClick={() => setRemoteDiagOpen(false)}>Schliessen</button>
+              {remoteDiag?.status.running && (
+                <button className="btn danger" onClick={() => { void onDisableRemoteDiagnostics(); }} disabled={remoteDiagBusy}>Deaktivieren</button>
+              )}
+              <button className="btn accent" onClick={() => { void onSubmitRemoteDiagnostics(); }} disabled={remoteDiagBusy}>
+                {remoteDiag?.status.running ? "Aktualisieren" : "Aktivieren"}
+              </button>
+            </div>
+          </div>
+        </div>
+      )}
+
      {deleteConfirm && (() => {
        const itemCount = [...deleteConfirm.ids].filter((id) => snapshot.session.items[id]).length;
        const pkgCount = [...deleteConfirm.ids].filter((id) => snapshot.session.packages[id]).length;
--- a/src/renderer/styles.css
+++ b/src/renderer/styles.css
@ -3360,3 +3360,110 @@ td {
 .rotation-event .rotation-time { color: var(--muted, #a59c8e); font-variant-numeric: tabular-nums; }
 .rotation-event .rotation-body strong { font-weight: 600; }
 .rotation-event .rotation-reason { color: var(--muted, #a59c8e); }
+
+.rd-status-line {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  font-size: 13px;
+  color: var(--text);
+}
+.rd-dot {
+  width: 9px;
+  height: 9px;
+  border-radius: 50%;
+  background: var(--muted);
+  flex: 0 0 auto;
+}
+.rd-dot.on {
+  background: #3fb950;
+}
+.rd-field {
+  display: grid;
+  gap: 5px;
+}
+.rd-field > label {
+  font-size: 13px;
+  font-weight: 600;
+  color: var(--text);
+}
+.rd-field input,
+.rd-field textarea {
+  width: 100%;
+  box-sizing: border-box;
+  background: var(--bg);
+  color: var(--text);
+  border: 1px solid var(--border);
+  border-radius: 8px;
+  padding: 8px 10px;
+  font-size: 13px;
+  font-family: inherit;
+}
+.rd-field input:focus,
+.rd-field textarea:focus {
+  outline: none;
+  border-color: var(--accent);
+}
+.rd-field textarea {
+  resize: vertical;
+  min-height: 62px;
+}
+.rd-field-inline {
+  grid-template-columns: 1fr 1fr;
+  gap: 10px;
+}
+.rd-hint {
+  font-size: 12px;
+  color: var(--muted);
+  line-height: 1.45;
+}
+.rd-seg {
+  display: flex;
+  width: fit-content;
+  border: 1px solid var(--border);
+  border-radius: 8px;
+  overflow: hidden;
+}
+.rd-seg button {
+  background: transparent;
+  color: var(--muted);
+  border: none;
+  padding: 7px 14px;
+  cursor: pointer;
+  font-size: 13px;
+  font-weight: 600;
+}
+.rd-seg button.active {
+  background: var(--accent);
+  color: #1a1206;
+}
+.rd-chips {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 6px;
+}
+.rd-chip {
+  background: var(--surface);
+  border: 1px solid var(--border);
+  border-radius: 6px;
+  padding: 3px 9px;
+  font-size: 12px;
+  cursor: pointer;
+  color: var(--muted);
+}
+.rd-chip:hover {
+  color: var(--text);
+  border-color: var(--accent);
+}
+.rd-code {
+  font-family: ui-monospace, "Cascadia Code", monospace;
+  font-size: 12px;
+  word-break: break-all;
+  background: var(--bg);
+  border: 1px solid var(--border);
+  border-radius: 8px;
+  padding: 9px 10px;
+  max-height: 120px;
+  overflow-y: auto;
+  color: var(--text);
+}
--- a/src/shared/ipc.ts
+++ b/src/shared/ipc.ts
@ -52,6 +52,10 @@ export const IPC_CHANNELS = {
  GET_TRACE_CONFIG: "app:get-trace-config",
  SET_TRACE_ENABLED: "app:set-trace-enabled",
  ROTATE_DEBUG_TOKEN: "app:rotate-debug-token",
+  GET_REMOTE_DIAGNOSTICS: "app:get-remote-diagnostics",
+  ENABLE_REMOTE_DIAGNOSTICS: "app:enable-remote-diagnostics",
+  DISABLE_REMOTE_DIAGNOSTICS: "app:disable-remote-diagnostics",
+  ROTATE_REMOTE_DIAGNOSTICS_TOKEN: "app:rotate-remote-diagnostics-token",
  OPEN_REALDEBRID_LOGIN: "app:open-realdebrid-login",
  OPEN_ALLDEBRID_LOGIN: "app:open-alldebrid-login",
  IMPORT_BESTDEBRID_COOKIES: "app:import-bestdebrid-cookies",
--- a/src/shared/preload-api.ts
+++ b/src/shared/preload-api.ts
@ -7,8 +7,10 @@ import type {
  DebridLinkHostLimitInfo,
  DebridProvider,
  DuplicatePolicy,
+  EnableRemoteDiagnosticsInput,
  HistoryEntry,
  PackagePriority,
+  RemoteDiagnosticsInfo,
  RendererErrorReport,
  SessionStats,
  StartConflictEntry,
@ -71,6 +73,10 @@ export interface ElectronApi {
  getTraceConfig: () => Promise<SupportTraceConfig>;
  setTraceEnabled: (enabled: boolean, note?: string, durationMinutes?: number) => Promise<SupportTraceConfig>;
  rotateDebugToken: () => Promise<{ path: string }>;
+  getRemoteDiagnostics: () => Promise<RemoteDiagnosticsInfo>;
+  enableRemoteDiagnostics: (input: EnableRemoteDiagnosticsInput) => Promise<RemoteDiagnosticsInfo>;
+  disableRemoteDiagnostics: () => Promise<RemoteDiagnosticsInfo>;
+  rotateRemoteDiagnosticsToken: () => Promise<RemoteDiagnosticsInfo>;
  openRealDebridLogin: () => Promise<void>;
  openAllDebridLogin: () => Promise<void>;
  importBestDebridCookies: () => Promise<number>;
--- a/src/shared/types.ts
+++ b/src/shared/types.ts
@ -134,6 +134,7 @@ export interface AppSettings {
  hideExtractedItems: boolean;
  confirmDeleteSelection: boolean;
  backupIncludeDownloads: boolean;
+  backupIncludeMcp: boolean;
  notifyUrl: string;
  notifyMention: string;
  notifyOnPackageCompleted: boolean;
@ -537,3 +538,30 @@ export interface RendererErrorReport {
  column?: number;
  componentStack?: string;
 }
+
+export interface RemoteDiagnosticsStatus {
+  running: boolean;
+  host: string;
+  port: number;
+  hasToken: boolean;
+  localOnly: boolean;
+  allowlistCount: number;
+}
+
+export interface RemoteDiagnosticsInfo {
+  status: RemoteDiagnosticsStatus;
+  code: string | null;
+  publicHost: string;
+  name: string;
+  allowlist: string[];
+  suggestedHosts: string[];
+}
+
+export interface EnableRemoteDiagnosticsInput {
+  hostMode: "local" | "network";
+  publicHost: string;
+  port?: number;
+  allowlist: string[];
+  name?: string;
+  rotateToken?: boolean;
+}
--- a/tasks/todo.md
+++ b/tasks/todo.md
@ -1,37 +1,42 @@
-# Massives Conversion-Logging (v1.7.213) + Failover-Fix
+# MCP-Ferndiagnose (Goal, ultracode) — v1.7.223

-## Problem (live belegt, 2026-06-17)
- Links haengen mit "Unrestrict Timeout nach 60s", R53/R64, halten Download-Slot → Stop-and-Go.
- Web-first: 1 globaler 60s-Timeout um die GANZE Provider-Kette → Web frisst das Budget,
-  API-Failover wird NIE versucht (debrid.ts 3801 `signal.aborted` → throw). Retry startet wieder bei Web.
- API-first laeuft "um einiges fluessiger" (User bestaetigt: API resolved UND downloaded auf dem Server).
- ABER: API-Token-Fehler ("Token error, please log-in") + "Login oder Unrestrict fehlgeschlagen"
-  → beide Accounts kriegen Cooldown → Doom-Loop. connectApi single-flightet Logins schon (pendingConnects),
-  also ist die Token-Ursache NICHT trivial → braucht Token-Lifecycle-Logging.
+## Ziel (Nutzer)
+"Baue massive Diagnose-Funktionen ein (MCP), so dass ich MCP auf nem Windows-Server aktivieren kann und du
+auf den Server zugreifst und WIRKLICH ALLES siehst (State, Fehler, Logs, Probleme). 5-6 Server, ueber
+Verbindungscode. Du verbindest dich → liest alles → behebst Probleme direkt."

-## Kern-Blindstelle
-Bestehende Logs (account-rotation.log) zeigen `elapsedMs` aber NICHT:
- queue-wait vs aktive Arbeit (war der 60s-Timeout Warten in der Queue oder echtes Arbeiten?)
- Token-Lifecycle (cacheHit/freshLogin/invalidation) → woher "Token error"?
- Provider-Ketten-Entscheidung pro Item (welche Provider, welches Budget, warum Stopp)
- Was war in-flight als der Caller-60s-Timeout feuerte (Provider/Account/Phase) + Slot-Belegung
+## Architektur (Advisor-bestaetigt v1)
+- Standalone **stdio MCP-Bridge** auf MEINER (Claude-Code-)Maschine, proxyt zur bestehenden HTTP `debug-server.ts`
+  jedes Servers via **Verbindungscode**. Eine Bridge bedient alle 5-6 Server.
+- KEIN eingebettetes MCP-over-HTTP (verworfen: hand-rolled Protokoll auf Internet-Oberflaeche = mehr Risiko).
+- Bridge-Code identisch fuer Direkt-IP vs spaeterer Tunnel (proxyt host:port).
+- Verbindungscode: `rddiag:v1:<base64url(JSON {v,h:host,p:port,t:token,n?:name,fp?:certFp})>`. Nutzer liefert
+  oeffentlichen Host (nicht auto-detecten).

-## Plan (Release 213 = NUR Logging, bewusst KEINE Verhaltensaenderung — damit das naechste Bundle das ECHTE aktuelle Verhalten zeigt)
- [x] `src/main/conversion-trace.ts`: AsyncLocalStorage-Trace + dedizierte `conversion.log`. EIN strukturierter Block pro Unrestrict-Versuch.
- [x] Wiring: init in app-controller, shutdown, support-bundle.
- [x] Instrumentiert (nur tracePhase-Calls, additiv, no-op ohne aktiven Trace):
-      - download-manager unrestrict-Boundary: runWithConversionTrace + Caller-Timeout-Attribution + describeSlotOccupancy.
-      - debrid.ts Provider-Kette: chain-try/chain-ok/chain-failed/chain-aborted (zeigt ob Failover feuert).
-      - debrid.ts Mega-Rotation: mega-account workMs + outcome (ok/failed/fatal/aborted) + cooldown.
-      - MegaDebridClient connectApi/doConnectApi/unrestrictViaApi: token cached/pending-join/fresh-login + connectMs + getLink response_code/text (DAS klaert "Token error").
-      - mega-web-fallback runExclusive: web-queue queueWaitMs + workMs (DAS klaert ob 60s = Warten oder Arbeit).
- [x] Test: conversion-trace.test.ts (Formatter + ALS-Kontext). tsc unveraendert 6.
- [ ] Build + Suite gruen. Release 213 (Gitea + Mirror).
+## Sicherheitsmodell (Advisor, first-class)
+Plain HTTP + Bearer ueber Internet = sniffbares Token mit Lesezugriff auf sensible Logs. Mitigations:
+- App-seitige IP-Allowlist (extractDebugClientIp existiert schon).
+- `/trace/config` MUTIERT → "read-only"-Claim auditieren: Writes von Remote-Oberflaeche gaten oder umlabeln.
+- Opt-in + sofort widerrufbar (Token-Rotation killt Zugang).
+- debug_token.txt in userData bestaetigen (ueberlebt Auto-Update).
+- Optional self-signed Cert + Fingerprint im Code gepinnt (NICHT v1-blockierend).

-## DEFERRED auf 214 (erst NACH Logs, kein Blind-Fix mehr)
- 60s global → per-Provider-Budget (Failover feuert) — proven, aber erst messen: tritt der 60s ueberhaupt bei API-first auf, und ist es Queue oder Arbeit?
- API Token-Error Doom-Loop ("Token error, please log-in") — Mechanismus per conversion.log verifizieren, DANN fixen (evtl. per-Account-Serialisierung fuer API wie bei Web).
- Config-Realitaet an User: 2. Account (xe) lief abgelaufen/deaktiviert → 212-Parallelitaet griff nicht; API-first ist der schnelle Pfad.
+## Phasen
+- [x] **P0 Vertical Slice (Diskriminator) — ERLEDIGT, harness ALL PASS:** Bridge → debug-server via stdio JSON-RPC, echte Daten zurueck.
+  - [x] MCP SDK API holen (context7) → @modelcontextprotocol/sdk 1.29.0, registerTool(name,{inputSchema:zodShape},cb)
+  - [x] Bridge in `tools/rd-diagnostics-mcp/` (eigenes package.json, NICHT in App-Bundle): code.mjs/http.mjs/bridge.mjs/gen-code.mjs
+  - [x] 14 Tools: rd_servers/rd_ping/rd_diagnostics/rd_status/rd_items/rd_packages/rd_errors/rd_logs/rd_history/rd_accounts/rd_host/rd_self_check/rd_get + Multi-Server (code|server|RDDIAG_CODE|RDDIAG_SERVERS)
+  - [x] Verbindungscode-Codec rddiag:v1:base64url({v,h,p,t,n?,fp?,s?})
+  - [x] Test-Harness (test/harness.mjs): fake debug-server (auth+routes+query-echo) + Bridge als stdio-Child → 19 Checks gruen (handshake, tools/list, ping, diagnostics+query-passthrough, logs-mapping, errors, escape-hatch, 401, missing-code, unreachable+hint)
+- [x] **P1 Security-Hardening — ERLEDIGT:** IP-Allowlist (exakt+CIDR), erzwungen VOR Auth am ECHTEN Socket-Peer (req.socket.remoteAddress), NICHT X-Forwarded-For (Advisor: XFF faelschbar → Bypass; gefixt+Threat-Test). Fail-closed. /trace/config belassen (zeitbegrenzt). userData/runtime verifiziert. Log-Audit: keine Secrets in /logs/*.
+- [x] **P2 One-Click-Enable + Code — ERLEDIGT:** restartDebugServer ('close'+closeAllConnections, EADDRINUSE). IPC get/enable/disable/rotate + Controller + Typen. Flache Modal-UI (Hilfe→Remote-Support→"Ferndiagnose (MCP)"): Status, lokal/netzwerk, Public-Host+Chips, Allowlist, Code+Copy+Token-Rotation+Deaktivieren.
+- [x] **P3 — durch bestehende Endpunkte abgedeckt:** /accounts (Cooldown/Rotation), /errors, /status, /diagnostics via Bridge. Kein neuer Endpunkt noetig.
+- [x] **P4 Verify — ERLEDIGT:** Suite 906 gruen, tsc=6, Harness gruen, Advisor (fing XFF-Bypass). Release v1.7.223 Gitea (6b52678, 4 Assets) + Mirror (24485be, 4 Assets, Claude-frei). Bridge `claude mcp add` (user, ✔ Connected).
+- [ ] **P5 Reachability (NUTZER):** Ferndiagnose auf 1 Server an → Code an mich → ich verbinde. Entscheid: Tunnel (sicherste, "Nur lokal") vs Direkt-Bind 0.0.0.0+Allowlist (nur vertrauenswuerdiges Netz/VPN; Token reist plain HTTP).

 ## Review
-Logging-Release: pure Diagnose, null Verhaltensrisiko. Naechster Schritt: User reproduziert, schickt Bundle, conversion.log zeigt Queue-vs-Arbeit + Token-Lifecycle eindeutig → praeziser Fix in 214.
+Vertikaler Slice zuerst (Bridge gegen Fake-Debug-Server, JSON-RPC stdio), dann App-Seite load-bearing-first
+(Backend+Tests vor UI). Advisor fing einen releaseblockierenden Bug: Allowlist nutzte extractDebugClientIp
+(X-Forwarded-For zuerst = angreiferkontrolliert) → Bypass per `X-Forwarded-For: 127.0.0.1`; Tests maskierten es
+(injizierten die IP per genau dem Header). Fix: Enforcement am Socket-Peer, XFF nur fuers Log; Threat-Test
+(socket 8.8.8.8 + XFF 127.0.0.1 → denied). Empfohlener Transport: Loopback+Tunnel; Direkt-Bind nur mit Allowlist.
--- a/tests/backup-mcp.test.ts
+++ b/tests/backup-mcp.test.ts
@ -0,0 +1,232 @@
+import fs from "node:fs";
+import http from "node:http";
+import os from "node:os";
+import path from "node:path";
+import { once } from "node:events";
+import { afterEach, describe, expect, it } from "vitest";
+
+import { buildBackupPayload, resolveMcpRemoteRestore, BackupMcpRemote } from "../src/main/backup-payload";
+import { defaultSettings } from "../src/main/constants";
+import { normalizeSettings } from "../src/main/storage";
+import {
+  startDebugServer,
+  stopDebugServer,
+  restartDebugServer,
+  writeDebugServerConfig,
+  getDebugAllowlist,
+  getDebugServerRuntimeStatus
+} from "../src/main/debug-server";
+import type { DownloadManager } from "../src/main/download-manager";
+import type { AppSettings, SessionState } from "../src/shared/types";
+
+const tempDirs: string[] = [];
+
+function input(settingsOverride: Partial<AppSettings>, mcpRemote?: BackupMcpRemote) {
+  return {
+    settings: { ...defaultSettings(), ...settingsOverride } as AppSettings,
+    appVersion: "1.7.224",
+    exportedAt: "2026-06-19T00:00:00.000Z",
+    session: {} as unknown as SessionState,
+    history: [],
+    mcpRemote
+  };
+}
+
+async function getFreePort(): Promise<number> {
+  const probe = http.createServer();
+  probe.listen(0, "127.0.0.1");
+  await once(probe, "listening");
+  const address = probe.address();
+  if (!address || typeof address === "string") {
+    throw new Error("port probe failed");
+  }
+  probe.close();
+  await once(probe, "close");
+  return address.port;
+}
+
+async function waitForReady(url: string): Promise<void> {
+  const deadline = Date.now() + 5000;
+  while (Date.now() < deadline) {
+    try {
+      const res = await fetch(url);
+      if (res.ok) {
+        return;
+      }
+    } catch {
+    }
+    await new Promise((resolve) => setTimeout(resolve, 40));
+  }
+  throw new Error(`debug server not ready: ${url}`);
+}
+
+afterEach(() => {
+  stopDebugServer();
+  while (tempDirs.length > 0) {
+    const dir = tempDirs.pop();
+    if (!dir) {
+      continue;
+    }
+    try {
+      fs.rmSync(dir, { recursive: true, force: true });
+    } catch {
+    }
+  }
+});
+
+describe("backup mcpRemote export gating", () => {
+  it("includes mcpRemote when backupIncludeMcp is on", () => {
+    const section: BackupMcpRemote = { allowlist: ["10.0.0.5", "192.168.1.0/24"], port: 9999, hostMode: "network" };
+    const payload = buildBackupPayload(input({ backupIncludeMcp: true }, section));
+    expect(payload.mcpRemote).toEqual(section);
+  });
+
+  it("omits mcpRemote when the toggle is off even if a section is provided", () => {
+    const payload = buildBackupPayload(input({ backupIncludeMcp: false }, { allowlist: ["10.0.0.5"], port: 9868, hostMode: "network" }));
+    expect(payload.mcpRemote).toBeUndefined();
+  });
+
+  it("omits mcpRemote when toggle on but no section gathered", () => {
+    const payload = buildBackupPayload(input({ backupIncludeMcp: true }, undefined));
+    expect(payload.mcpRemote).toBeUndefined();
+  });
+
+  it("the mcpRemote section carries ONLY allowlist/port/hostMode (no token, publicHost, name)", () => {
+    const payload = buildBackupPayload(input({ backupIncludeMcp: true }, { allowlist: ["10.0.0.5"], port: 9868, hostMode: "network" }));
+    expect(payload.mcpRemote && Object.keys(payload.mcpRemote).sort()).toEqual(["allowlist", "hostMode", "port"]);
+    const sectionJson = JSON.stringify(payload.mcpRemote);
+    expect(sectionJson.toLowerCase()).not.toContain("token");
+    expect(sectionJson).not.toContain("publicHost");
+    expect(sectionJson.toLowerCase()).not.toContain("\"name\"");
+  });
+});
+
+describe("backupIncludeMcp settings persistence", () => {
+  it("normalizeSettings preserves backupIncludeMcp (the toggle survives save/load)", () => {
+    expect(normalizeSettings({ backupIncludeMcp: true } as unknown as AppSettings).backupIncludeMcp).toBe(true);
+    expect(normalizeSettings({ backupIncludeMcp: false } as unknown as AppSettings).backupIncludeMcp).toBe(false);
+    expect(normalizeSettings({} as unknown as AppSettings).backupIncludeMcp).toBe(false);
+  });
+});
+
+describe("resolveMcpRemoteRestore", () => {
+  it("maps network + non-empty allowlist to 0.0.0.0", () => {
+    expect(resolveMcpRemoteRestore({ allowlist: ["10.0.0.5"], port: 9868, hostMode: "network" }))
+      .toEqual({ host: "0.0.0.0", port: 9868, allowlist: ["10.0.0.5"] });
+  });
+
+  it("SAFETY: network with EMPTY allowlist binds local, never 0.0.0.0", () => {
+    expect(resolveMcpRemoteRestore({ allowlist: [], port: 9868, hostMode: "network" })?.host).toBe("127.0.0.1");
+  });
+
+  it("maps local to 127.0.0.1", () => {
+    expect(resolveMcpRemoteRestore({ allowlist: ["10.0.0.5"], port: 9868, hostMode: "local" })?.host).toBe("127.0.0.1");
+  });
+
+  it("rejects an out-of-range or non-integer port", () => {
+    expect(resolveMcpRemoteRestore({ allowlist: ["10.0.0.5"], port: 80, hostMode: "network" })?.port).toBeUndefined();
+    expect(resolveMcpRemoteRestore({ allowlist: ["10.0.0.5"], port: 70000, hostMode: "network" })?.port).toBeUndefined();
+    expect(resolveMcpRemoteRestore({ allowlist: ["10.0.0.5"], port: 9868.5, hostMode: "network" })?.port).toBeUndefined();
+  });
+
+  it("filters non-string and blank allowlist entries and trims", () => {
+    const r = resolveMcpRemoteRestore({ allowlist: ["10.0.0.5", "", "  ", 5, null, " 8.8.8.8 "], port: 9868, hostMode: "network" });
+    expect(r?.allowlist).toEqual(["10.0.0.5", "8.8.8.8"]);
+  });
+
+  it("returns null for missing or empty/invalid sections", () => {
+    expect(resolveMcpRemoteRestore(undefined)).toBeNull();
+    expect(resolveMcpRemoteRestore(null)).toBeNull();
+    expect(resolveMcpRemoteRestore("x")).toBeNull();
+    expect(resolveMcpRemoteRestore({})).toBeNull();
+  });
+});
+
+describe("backup mcpRemote live restore round-trip", () => {
+  it("export -> resolve -> apply is reflected in the running debug-server (proves restart fired)", async () => {
+    const baseDir = fs.mkdtempSync(path.join(os.tmpdir(), "rd-bkmcp-"));
+    tempDirs.push(baseDir);
+    const startPort = await getFreePort();
+    const restorePort = await getFreePort();
+    fs.writeFileSync(path.join(baseDir, "debug_token.txt"), "rt-secret", "utf8");
+    fs.writeFileSync(path.join(baseDir, "debug_port.txt"), String(startPort), "utf8");
+    fs.writeFileSync(path.join(baseDir, "debug_host.txt"), "127.0.0.1", "utf8");
+    fs.writeFileSync(path.join(baseDir, "debug_allowlist.txt"), "", "utf8");
+    startDebugServer({} as unknown as DownloadManager, baseDir);
+    await waitForReady(`http://127.0.0.1:${startPort}/health?token=rt-secret`);
+    expect(getDebugAllowlist()).toEqual([]);
+
+    const payload = buildBackupPayload(input(
+      { backupIncludeMcp: true },
+      { allowlist: ["203.0.113.4", "10.0.0.0/24"], port: restorePort, hostMode: "network" }
+    ));
+
+    const restore = resolveMcpRemoteRestore(payload.mcpRemote);
+    expect(restore).not.toBeNull();
+    writeDebugServerConfig({ host: restore!.host, port: restore!.port, allowlist: restore!.allowlist });
+    const status = await restartDebugServer();
+
+    expect(getDebugAllowlist()).toEqual(["203.0.113.4", "10.0.0.0/24"]);
+    expect(status.port).toBe(restorePort);
+    expect(status.host).toBe("0.0.0.0");
+    expect(status.allowlistCount).toBe(2);
+
+    expect(fs.readFileSync(path.join(baseDir, "debug_token.txt"), "utf8").trim()).toBe("rt-secret");
+    expect(fs.existsSync(path.join(baseDir, "debug_remote.json"))).toBe(false);
+
+    await waitForReady(`http://127.0.0.1:${restorePort}/health?token=rt-secret`);
+  });
+
+  it("full-backup path writes the debug_* files to disk without a restart (boot picks them up)", async () => {
+    const baseDir = fs.mkdtempSync(path.join(os.tmpdir(), "rd-bkmcp2-"));
+    tempDirs.push(baseDir);
+    const startPort = await getFreePort();
+    fs.writeFileSync(path.join(baseDir, "debug_token.txt"), "rt2", "utf8");
+    fs.writeFileSync(path.join(baseDir, "debug_port.txt"), String(startPort), "utf8");
+    fs.writeFileSync(path.join(baseDir, "debug_host.txt"), "127.0.0.1", "utf8");
+    fs.writeFileSync(path.join(baseDir, "debug_allowlist.txt"), "", "utf8");
+    startDebugServer({} as unknown as DownloadManager, baseDir);
+    await waitForReady(`http://127.0.0.1:${startPort}/health?token=rt2`);
+
+    const restore = resolveMcpRemoteRestore({ allowlist: ["198.51.100.9"], port: 9100, hostMode: "network" });
+    writeDebugServerConfig({ host: restore!.host, port: restore!.port, allowlist: restore!.allowlist });
+
+    expect(fs.readFileSync(path.join(baseDir, "debug_host.txt"), "utf8").trim()).toBe("0.0.0.0");
+    expect(fs.readFileSync(path.join(baseDir, "debug_port.txt"), "utf8").trim()).toBe("9100");
+    expect(fs.readFileSync(path.join(baseDir, "debug_allowlist.txt"), "utf8")).toContain("198.51.100.9");
+    expect(getDebugServerRuntimeStatus().port).toBe(startPort);
+  });
+});
+
+describe("debug-server live diagnostics endpoints", () => {
+  it("serves /providers (live cooldown/runtime snapshot) and /logs/conversion over authenticated HTTP", async () => {
+    const baseDir = fs.mkdtempSync(path.join(os.tmpdir(), "rd-prov-"));
+    tempDirs.push(baseDir);
+    const port = await getFreePort();
+    fs.writeFileSync(path.join(baseDir, "debug_token.txt"), "prov-secret", "utf8");
+    fs.writeFileSync(path.join(baseDir, "debug_port.txt"), String(port), "utf8");
+    fs.writeFileSync(path.join(baseDir, "debug_host.txt"), "127.0.0.1", "utf8");
+    fs.writeFileSync(path.join(baseDir, "debug_allowlist.txt"), "", "utf8");
+    startDebugServer({} as unknown as DownloadManager, baseDir);
+    await waitForReady(`http://127.0.0.1:${port}/health?token=prov-secret`);
+
+    const provRes = await fetch(`http://127.0.0.1:${port}/providers?token=prov-secret`);
+    expect(provRes.status).toBe(200);
+    const prov = await provRes.json();
+    expect(typeof prov.capturedAtMs).toBe("number");
+    expect(prov.megaDebrid).toBeTruthy();
+    expect(Array.isArray(prov.megaDebrid.accounts)).toBe(true);
+    expect(typeof prov.megaDebrid.rotationCursor).toBe("number");
+    expect(prov.debridLink).toBeTruthy();
+    expect(Array.isArray(prov.debridLink.keys)).toBe(true);
+
+    const unauth = await fetch(`http://127.0.0.1:${port}/providers`);
+    expect(unauth.status).toBe(401);
+
+    const convRes = await fetch(`http://127.0.0.1:${port}/logs/conversion?token=prov-secret`);
+    expect(convRes.status).toBe(200);
+    const conv = await convRes.json();
+    expect(Array.isArray(conv.lines)).toBe(true);
+    expect(conv).toHaveProperty("available");
+  });
+});
--- a/tests/connection-code.test.ts
+++ b/tests/connection-code.test.ts
@ -0,0 +1,42 @@
+import { describe, it, expect } from "vitest";
+import { encodeConnectionCode } from "../src/main/connection-code";
+import { decodeConnectionCode } from "../tools/rd-diagnostics-mcp/src/code.mjs";
+
+describe("connection-code", () => {
+  it("round-trips through the bridge decoder", () => {
+    const code = encodeConnectionCode({ host: "203.0.113.5", port: 9868, token: "deadbeef", name: "server-1" });
+    expect(code.startsWith("rddiag:v1:")).toBe(true);
+    const decoded = decodeConnectionCode(code);
+    expect(decoded.host).toBe("203.0.113.5");
+    expect(decoded.port).toBe(9868);
+    expect(decoded.token).toBe("deadbeef");
+    expect(decoded.name).toBe("server-1");
+    expect(decoded.scheme).toBe("http");
+  });
+
+  it("carries https scheme and fingerprint when set", () => {
+    const code = encodeConnectionCode({
+      host: "diag.example.com",
+      port: 8443,
+      token: "abc",
+      scheme: "https",
+      fingerprint: "AA:BB:CC"
+    });
+    const decoded = decodeConnectionCode(code);
+    expect(decoded.scheme).toBe("https");
+    expect(decoded.fingerprint).toBe("AA:BB:CC");
+  });
+
+  it("omits scheme key for plain http (default)", () => {
+    const code = encodeConnectionCode({ host: "10.0.0.2", port: 9868, token: "t" });
+    const json = JSON.parse(Buffer.from(code.slice("rddiag:v1:".length).replace(/-/g, "+").replace(/_/g, "/"), "base64").toString("utf8"));
+    expect(json.s).toBeUndefined();
+    expect(json).toMatchObject({ v: 1, h: "10.0.0.2", p: 9868, t: "t" });
+  });
+
+  it("rejects invalid input", () => {
+    expect(() => encodeConnectionCode({ host: "", port: 9868, token: "t" })).toThrow();
+    expect(() => encodeConnectionCode({ host: "h", port: 0, token: "t" })).toThrow();
+    expect(() => encodeConnectionCode({ host: "h", port: 9868, token: "" })).toThrow();
+  });
+});
--- a/tests/debrid.test.ts
+++ b/tests/debrid.test.ts
@ -3,7 +3,8 @@ import { defaultSettings, REQUEST_RETRIES } from "../src/main/constants";
 import { parseDebridLinkApiKeys } from "../src/shared/debrid-link-keys";
 import { getMegaDebridAccountId } from "../src/shared/mega-debrid-accounts";
 import { getProviderUsageDayKey } from "../src/shared/provider-daily-limits";
-import { classifyMegaDebridAccountFailureForTests, clearMegaDebridEmptyResponseStreak, DebridService, extractRapidgatorFilenameFromHtml, fetchAllDebridHostInfo, fetchDebridLinkHostLimits, filenameFromRapidgatorUrlPath, getDebridLinkKeyCooldownStateForTests, getDebridLinkKeyRuntimeStateForTests, getMegaDebridAccountCooldownState, leadProviderChainWith, MEGA_DEBRID_EMPTY_STREAK_UNTIL_RESTART, MEGA_DEBRID_STICKY_LINKS, normalizeResolvedFilename, primeMegaDebridUntilRestartForTests, recordMegaDebridEmptyResponseStreak, resetDebridLinkRuntimeStateForTests, resetMegaDebridRuntimeStateForTests } from "../src/main/debrid";
+import { isMegaDebridTransientResolveFailure } from "../src/shared/mega-debrid-errors";
+import { classifyMegaDebridAccountFailureForTests, clearMegaDebridEmptyResponseStreak, DebridService, extractRapidgatorFilenameFromHtml, fetchAllDebridHostInfo, fetchDebridLinkHostLimits, filenameFromRapidgatorUrlPath, getDebridLinkKeyCooldownStateForTests, getDebridLinkKeyRuntimeStateForTests, getMegaDebridAccountCooldownState, getProviderRuntimeSnapshot, leadProviderChainWith, MEGA_DEBRID_EMPTY_STREAK_UNTIL_RESTART, MEGA_DEBRID_STICKY_LINKS, normalizeResolvedFilename, primeMegaDebridRuntimeCooldownForTests, primeMegaDebridUntilRestartForTests, recordMegaDebridEmptyResponseStreak, resetDebridLinkRuntimeStateForTests, resetMegaDebridRuntimeStateForTests } from "../src/main/debrid";

 const originalFetch = globalThis.fetch;

@ -2070,9 +2071,76 @@ describe("debrid service", () => {
    expect(calls).toBeGreaterThanOrEqual(1);
  }, 20000);

+  it("getProviderRuntimeSnapshot surfaces a live Mega-Debrid account cooldown (until/remaining/reason) for the diagnostics endpoint", () => {
+    const accId = getMegaDebridAccountId("user");
+    const key = `${accId}:web`;
+    expect(getProviderRuntimeSnapshot().megaDebrid.accounts.find((a) => a.key === key)?.cooldown ?? null).toBeNull();
+
+    primeMegaDebridRuntimeCooldownForTests(key, 90_000, "Abbruch/Timeout nach 60s");
+
+    const snap = getProviderRuntimeSnapshot();
+    expect(typeof snap.capturedAtMs).toBe("number");
+    const acc = snap.megaDebrid.accounts.find((a) => a.key === key);
+    expect(acc).toBeTruthy();
+    expect(acc!.cooldown).not.toBeNull();
+    expect(acc!.cooldown!.remainingMs).toBeGreaterThan(0);
+    expect(acc!.cooldown!.remainingMs).toBeLessThanOrEqual(90_000);
+    expect(acc!.cooldown!.untilMs).toBeGreaterThan(snap.capturedAtMs);
+    expect(acc!.cooldown!.message).toContain("Abbruch");
+  });
+
+  it("single Mega-Debrid account: a long Web abort parks only the slow link and does NOT freeze the sole account", async () => {
+    process.env.RD_MEGA_ABORT_MIN_RUN_MS = "0";
+    const settings = {
+      ...defaultSettings(),
+      token: "",
+      bestToken: "",
+      allDebridToken: "",
+      megaLogin: "user",
+      megaPassword: "pass",
+      megaCredentials: "user:pass",
+      megaDebridPreferApi: false,
+      providerOrder: [] as const,
+      providerPrimary: "megadebrid" as const,
+      providerSecondary: "none" as const,
+      providerTertiary: "none" as const,
+      autoProviderFallback: false
+    };
+    globalThis.fetch = (async () => new Response("error", { status: 500 })) as typeof fetch;
+
+    const controller = new AbortController();
+    let calls = 0;
+    const megaWeb = vi.fn((): Promise<{ fileName: string; directUrl: string; fileSize: number | null; retriesUsed: number }> => {
+      calls += 1;
+      if (calls === 1) {
+        controller.abort("simulated-60s-timeout");
+        return Promise.reject(new Error("aborted"));
+      }
+      return Promise.resolve({
+        fileName: "healthy.rar",
+        directUrl: "https://www11.unrestrict.link/download/file/ok/healthy.rar",
+        fileSize: null,
+        retriesUsed: 0
+      });
+    });
+
+    const service = new DebridService(settings, { megaWebUnrestrict: megaWeb });
+
+    const err = await service.unrestrictLink("https://rapidgator.net/file/slow-link.rar.html", controller.signal).then(() => null, (e: unknown) => e);
+    expect(err).toBeTruthy();
+    expect(String(err)).toMatch(/mega_debrid_slow_link:\d+:/i);
+
+    const key = `${getMegaDebridAccountId("user")}:web`;
+    expect(getMegaDebridAccountCooldownState(key)).toBeNull();
+
+    const second = await service.unrestrictLink("https://rapidgator.net/file/healthy.rar.html");
+    expect(second.provider).toBe("megadebrid");
+    expect(calls).toBeGreaterThanOrEqual(2);
+  }, 20000);
+
  it("escalates a Mega-Debrid account to 'until restart' after the empty-response streak threshold", () => {
    const key = `${getMegaDebridAccountId("user1")}:web`;
-    expect(MEGA_DEBRID_EMPTY_STREAK_UNTIL_RESTART).toBe(3);
+    expect(MEGA_DEBRID_EMPTY_STREAK_UNTIL_RESTART).toBe(10);
    expect(recordMegaDebridEmptyResponseStreak(key)).toBe(1);
    expect(recordMegaDebridEmptyResponseStreak(key)).toBe(2);
    expect(recordMegaDebridEmptyResponseStreak(key)).toBe(3);
@ -2100,6 +2168,14 @@ describe("debrid service", () => {
    expect(genuineEmpty.limitSignal).toBe(true);
  });

+  it("classifies an empty Mega-Debrid API result ('Linkgenerierung lieferte kein Ergebnis') as a fast transient, not a 30s cooldown", () => {
+    const result = classifyMegaDebridAccountFailureForTests(new Error("Mega-Debrid API: Linkgenerierung lieferte kein Ergebnis"));
+    expect(result.fatal).toBe(false);
+    expect(result.cooldownMs).toBe(0);
+    expect(result.limitSignal).toBeFalsy();
+    expect(isMegaDebridTransientResolveFailure(result.message)).toBe(true);
+  });
+
  it("skips a Mega-Debrid account parked until restart and rotates to the next, without re-testing it", async () => {
    const settings = {
      ...defaultSettings(),
@ -2189,8 +2265,9 @@ describe("debrid service", () => {
    globalThis.fetch = (async () => new Response("error", { status: 500 })) as typeof fetch;

    const key = `${getMegaDebridAccountId("user1")}:web`;
+    for (let i = 0; i < MEGA_DEBRID_EMPTY_STREAK_UNTIL_RESTART - 1; i += 1) {
      recordMegaDebridEmptyResponseStreak(key);
-    recordMegaDebridEmptyResponseStreak(key);
+    }
    expect(getMegaDebridAccountCooldownState(key)?.untilRestart ?? false).toBe(false);

    const megaWeb = vi.fn(async () => null);
--- a/tests/debug-server-allowlist.test.ts
+++ b/tests/debug-server-allowlist.test.ts
@ -0,0 +1,146 @@
+import fs from "node:fs";
+import http from "node:http";
+import os from "node:os";
+import path from "node:path";
+import { once } from "node:events";
+import { afterEach, describe, expect, it } from "vitest";
+
+import {
+  startDebugServer,
+  stopDebugServer,
+  restartDebugServer,
+  writeDebugServerConfig,
+  getDebugServerRuntimeStatus,
+  evaluateClientAllowed,
+  getPeerIp
+} from "../src/main/debug-server";
+import type { DownloadManager } from "../src/main/download-manager";
+
+const tempDirs: string[] = [];
+const TOKEN = "allowlist-secret";
+
+async function getFreePort(): Promise<number> {
+  const probe = http.createServer();
+  probe.listen(0, "127.0.0.1");
+  await once(probe, "listening");
+  const address = probe.address();
+  if (!address || typeof address === "string") {
+    throw new Error("port probe failed");
+  }
+  probe.close();
+  await once(probe, "close");
+  return address.port;
+}
+
+async function waitForReady(url: string): Promise<void> {
+  const deadline = Date.now() + 5000;
+  while (Date.now() < deadline) {
+    try {
+      const res = await fetch(url);
+      if (res.ok) {
+        return;
+      }
+    } catch {
+    }
+    await new Promise((resolve) => setTimeout(resolve, 40));
+  }
+  throw new Error(`debug server not ready: ${url}`);
+}
+
+async function startWithAllowlist(allowlist: string[], host = "0.0.0.0"): Promise<{ baseUrl: string }> {
+  const baseDir = fs.mkdtempSync(path.join(os.tmpdir(), "rd-allow-"));
+  tempDirs.push(baseDir);
+  const port = await getFreePort();
+  fs.writeFileSync(path.join(baseDir, "debug_token.txt"), TOKEN, "utf8");
+  fs.writeFileSync(path.join(baseDir, "debug_port.txt"), String(port), "utf8");
+  fs.writeFileSync(path.join(baseDir, "debug_host.txt"), host, "utf8");
+  fs.writeFileSync(path.join(baseDir, "debug_allowlist.txt"), allowlist.join("\n"), "utf8");
+  const manager = {} as unknown as DownloadManager;
+  startDebugServer(manager, baseDir);
+  const baseUrl = `http://127.0.0.1:${port}`;
+  await waitForReady(`${baseUrl}/health?token=${TOKEN}`);
+  return { baseUrl };
+}
+
+afterEach(() => {
+  stopDebugServer();
+  while (tempDirs.length > 0) {
+    const dir = tempDirs.pop();
+    if (!dir) {
+      continue;
+    }
+    try {
+      fs.rmSync(dir, { recursive: true, force: true });
+    } catch {
+    }
+  }
+});
+
+describe("debug-server allowlist matcher (pure)", () => {
+  it("always allows loopback regardless of rules", () => {
+    expect(evaluateClientAllowed("127.0.0.1", [])).toBe(true);
+    expect(evaluateClientAllowed("::1", [])).toBe(true);
+    expect(evaluateClientAllowed("::ffff:127.0.0.1", ["8.8.8.8"])).toBe(true);
+  });
+
+  it("matches an exact allowlisted IP and rejects others", () => {
+    expect(evaluateClientAllowed("8.8.8.8", ["8.8.8.8"])).toBe(true);
+    expect(evaluateClientAllowed("9.9.9.9", ["8.8.8.8"])).toBe(false);
+  });
+
+  it("matches inside a CIDR and rejects outside it", () => {
+    expect(evaluateClientAllowed("10.0.0.42", ["10.0.0.0/24"])).toBe(true);
+    expect(evaluateClientAllowed("10.0.1.42", ["10.0.0.0/24"])).toBe(false);
+  });
+
+  it("fail-closed: empty rules reject every non-loopback client", () => {
+    expect(evaluateClientAllowed("203.0.113.7", [])).toBe(false);
+    expect(evaluateClientAllowed("8.8.8.8", [])).toBe(false);
+  });
+
+  it("derives the client IP from the socket peer, never from X-Forwarded-For", () => {
+    const forgedLoopback = {
+      socket: { remoteAddress: "8.8.8.8" },
+      headers: { "x-forwarded-for": "127.0.0.1" }
+    } as unknown as http.IncomingMessage;
+    expect(getPeerIp(forgedLoopback)).toBe("8.8.8.8");
+    expect(evaluateClientAllowed(getPeerIp(forgedLoopback), [])).toBe(false);
+    expect(evaluateClientAllowed(getPeerIp(forgedLoopback), ["9.9.9.9"])).toBe(false);
+    expect(evaluateClientAllowed(getPeerIp(forgedLoopback), ["8.8.8.8"])).toBe(true);
+
+    const ipv6Mapped = {
+      socket: { remoteAddress: "::ffff:10.0.0.5" },
+      headers: {}
+    } as unknown as http.IncomingMessage;
+    expect(getPeerIp(ipv6Mapped)).toBe("10.0.0.5");
+  });
+});
+
+describe("debug-server allowlist enforcement (wired)", () => {
+  it("allows a loopback connection and ignores a spoofed X-Forwarded-For", async () => {
+    const { baseUrl } = await startWithAllowlist(["8.8.8.8"]);
+    const plain = await fetch(`${baseUrl}/health?token=${TOKEN}`);
+    expect(plain.status).toBe(200);
+    const spoofed = await fetch(`${baseUrl}/health?token=${TOKEN}`, {
+      headers: { "X-Forwarded-For": "203.0.113.9" }
+    });
+    expect(spoofed.status).toBe(200);
+  });
+
+  it("still enforces the token for loopback clients", async () => {
+    const { baseUrl } = await startWithAllowlist(["8.8.8.8"]);
+    const res = await fetch(`${baseUrl}/health`);
+    expect(res.status).toBe(401);
+  });
+
+  it("reloads the allowlist live via restartDebugServer", async () => {
+    const { baseUrl } = await startWithAllowlist(["8.8.8.8"]);
+    expect(getDebugServerRuntimeStatus().allowlistCount).toBe(1);
+    writeDebugServerConfig({ allowlist: ["9.9.9.9", "10.0.0.0/24"] });
+    const status = await restartDebugServer();
+    expect(status.running).toBe(true);
+    expect(status.allowlistCount).toBe(2);
+    await waitForReady(`${baseUrl}/health?token=${TOKEN}`);
+    expect((await fetch(`${baseUrl}/health?token=${TOKEN}`)).status).toBe(200);
+  });
+});
--- a/tests/download-manager.test.ts
+++ b/tests/download-manager.test.ts
@ -14,7 +14,7 @@ import { getProviderUsageDayKey } from "../src/shared/provider-daily-limits";
 import { getItemLogPath, initItemLogs, shutdownItemLogs } from "../src/main/item-log";
 import { initPackageLogs, shutdownPackageLogs } from "../src/main/package-log";
 import { createStoragePaths, emptySession } from "../src/main/storage";
-import { primeDebridLinkRuntimeCooldownForTests, resetDebridLinkRuntimeStateForTests, primeMegaDebridRuntimeCooldownForTests, resetMegaDebridRuntimeStateForTests } from "../src/main/debrid";
+import { primeDebridLinkRuntimeCooldownForTests, resetDebridLinkRuntimeStateForTests, primeMegaDebridRuntimeCooldownForTests, resetMegaDebridRuntimeStateForTests, primeMegaDebridInFlightForTests } from "../src/main/debrid";
 import { getMegaDebridAccountId } from "../src/shared/mega-debrid-accounts";
 import { getRenameLogPath, initRenameLog, shutdownRenameLog } from "../src/main/rename-log";
 import { UnrestrictedLink } from "../src/main/realdebrid";
@ -2209,6 +2209,98 @@ describe("download manager", () => {
    expect(fs.statSync(item.targetPath).size).toBe(binary.length);
  });

+  it("recovers an HTTP 416 item with a clean fresh restart after the in-budget retries are exhausted", async () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "rd-416-fresh-"));
+    tempDirs.push(root);
+    const binary = Buffer.alloc(160 * 1024, 19);
+    const prevDelay = process.env.RD_HTTP416_FRESH_RESTART_DELAY_MS;
+    process.env.RD_HTTP416_FRESH_RESTART_DELAY_MS = "0";
+    let downloadCalls = 0;
+
+    globalThis.fetch = async (input: RequestInfo | URL): Promise<Response> => {
+      const url = typeof input === "string" ? input : input instanceof URL ? input.toString() : input.url;
+      if (url.includes("/unrestrict/link")) {
+        return new Response(JSON.stringify({ download: "https://dummy/direct-416-recover", filename: "fresh-416.mkv", filesize: binary.length }), { status: 200, headers: { "Content-Type": "application/json" } });
+      }
+      throw new Error(`unexpected fetch ${url}`);
+    };
+
+    try {
+      const manager = new DownloadManager(
+        { ...defaultSettings(), token: "rd-token", outputDir: path.join(root, "downloads"), extractDir: path.join(root, "extract"), retryLimit: 2, autoExtract: false, autoReconnect: false },
+        emptySession(),
+        createStoragePaths(path.join(root, "state"))
+      );
+
+      (manager as any).downloadToFile = async (_active: unknown, _directUrl: string, targetPath: string) => {
+        downloadCalls += 1;
+        if (downloadCalls <= 3) {
+          throw new Error("HTTP 416");
+        }
+        fs.mkdirSync(path.dirname(targetPath), { recursive: true });
+        fs.writeFileSync(targetPath, binary);
+        const item = Object.values((manager as any).session.items)[0] as { downloadedBytes: number; totalBytes: number; progressPercent: number } | undefined;
+        if (item) {
+          item.downloadedBytes = binary.length;
+          item.totalBytes = binary.length;
+          item.progressPercent = 100;
+        }
+        return { resumable: true };
+      };
+
+      manager.addPackages([{ name: "fresh-416", links: ["https://dummy/fresh-416"] }]);
+      await manager.start();
+      await waitFor(() => !manager.getSnapshot().session.running, 20000);
+
+      const item = Object.values(manager.getSnapshot().session.items)[0];
+      expect(item?.status).toBe("completed");
+      expect(downloadCalls).toBeGreaterThan(3);
+    } finally {
+      if (prevDelay === undefined) { delete process.env.RD_HTTP416_FRESH_RESTART_DELAY_MS; } else { process.env.RD_HTTP416_FRESH_RESTART_DELAY_MS = prevDelay; }
+    }
+  }, 25000);
+
+  it("bounds HTTP 416 clean restarts and finally fails instead of looping forever or stalling permanently", async () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "rd-416-cap-"));
+    tempDirs.push(root);
+    const prevDelay = process.env.RD_HTTP416_FRESH_RESTART_DELAY_MS;
+    process.env.RD_HTTP416_FRESH_RESTART_DELAY_MS = "0";
+    let downloadCalls = 0;
+
+    globalThis.fetch = async (input: RequestInfo | URL): Promise<Response> => {
+      const url = typeof input === "string" ? input : input instanceof URL ? input.toString() : input.url;
+      if (url.includes("/unrestrict/link")) {
+        return new Response(JSON.stringify({ download: "https://dummy/direct-416-forever", filename: "always-416.mkv", filesize: 1024 }), { status: 200, headers: { "Content-Type": "application/json" } });
+      }
+      throw new Error(`unexpected fetch ${url}`);
+    };
+
+    try {
+      const manager = new DownloadManager(
+        { ...defaultSettings(), token: "rd-token", outputDir: path.join(root, "downloads"), extractDir: path.join(root, "extract"), retryLimit: 0, autoExtract: false, autoReconnect: false },
+        emptySession(),
+        createStoragePaths(path.join(root, "state"))
+      );
+
+      (manager as any).downloadToFile = async () => {
+        downloadCalls += 1;
+        throw new Error("direct_link_retry_exhausted:HTTP 416");
+      };
+
+      manager.addPackages([{ name: "always-416", links: ["https://dummy/always-416"] }]);
+      await manager.start();
+      await waitFor(() => !manager.getSnapshot().session.running, 20000);
+
+      const item = Object.values(manager.getSnapshot().session.items)[0];
+      expect(item?.status).toBe("failed");
+      expect(downloadCalls).toBeGreaterThan(4);
+      expect(downloadCalls).toBeLessThan(30);
+      expect((manager as any).http416FreshRestartByItem.get(item.id)).toBeUndefined();
+    } finally {
+      if (prevDelay === undefined) { delete process.env.RD_HTTP416_FRESH_RESTART_DELAY_MS; } else { process.env.RD_HTTP416_FRESH_RESTART_DELAY_MS = prevDelay; }
+    }
+  }, 25000);
+
  it("retries HTTP 416 in-session when using Debrid-Link API and then completes", async () => {
    const root = fs.mkdtempSync(path.join(os.tmpdir(), "rd-dm-"));
    tempDirs.push(root);
@ -12244,3 +12336,200 @@ describe("download manager", () => {
    }
  });
 });
+
+describe("start conflict guard + selective resume", () => {
+  function makeItem(id: string, packageId: string, status: string, fileName: string): any {
+    return {
+      id, packageId, url: `https://hoster.example/${id}`, provider: "realdebrid",
+      status, retries: 0, speedBps: 0, downloadedBytes: status === "completed" ? 100 : 0,
+      totalBytes: status === "completed" ? 100 : null, progressPercent: status === "completed" ? 100 : 0,
+      fileName, targetPath: "", resumable: true, attempts: 0, lastError: "", fullStatus: "",
+      createdAt: Date.now(), updatedAt: Date.now()
+    };
+  }
+
+  it("does not flag a partially-downloaded package whose extract dir holds its own completed output", async () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "rd-startconflict-own-"));
+    tempDirs.push(root);
+    const storagePaths = createStoragePaths(path.join(root, "state"));
+    initPackageLogs(storagePaths.baseDir);
+    initItemLogs(storagePaths.baseDir);
+
+    const session = emptySession();
+    const packageId = "pkg-own-output";
+    const extractDir = path.join(root, "extract", "OwnOutput");
+    fs.mkdirSync(extractDir, { recursive: true });
+    fs.writeFileSync(path.join(extractDir, "episode01.mkv"), Buffer.alloc(64, 7));
+    session.packageOrder = [packageId];
+    session.packages[packageId] = {
+      id: packageId, name: "OwnOutput",
+      outputDir: path.join(root, "downloads", "OwnOutput"), extractDir,
+      status: "queued", itemIds: ["own-done", "own-pending"], cancelled: false, enabled: true,
+      createdAt: Date.now(), updatedAt: Date.now()
+    } as any;
+    session.items["own-done"] = makeItem("own-done", packageId, "completed", "done.rar");
+    session.items["own-pending"] = makeItem("own-pending", packageId, "queued", "pending.rar");
+
+    const manager = new DownloadManager(
+      { ...defaultSettings(), token: "rd-token", outputDir: path.join(root, "downloads"), extractDir: path.join(root, "extract") },
+      session, storagePaths
+    );
+
+    const conflicts = await manager.getStartConflicts();
+    expect(conflicts.map((c) => c.packageId)).not.toContain(packageId);
+  });
+
+  it("flags a fresh package when its package-specific extract dir already holds files and it has no completed items", async () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "rd-startconflict-fresh-"));
+    tempDirs.push(root);
+    const storagePaths = createStoragePaths(path.join(root, "state"));
+    initPackageLogs(storagePaths.baseDir);
+    initItemLogs(storagePaths.baseDir);
+
+    const session = emptySession();
+    const packageId = "pkg-fresh-conflict";
+    const extractDir = path.join(root, "extract", "FreshConflict");
+    fs.mkdirSync(extractDir, { recursive: true });
+    fs.writeFileSync(path.join(extractDir, "old-from-previous-run.mkv"), Buffer.alloc(64, 9));
+    session.packageOrder = [packageId];
+    session.packages[packageId] = {
+      id: packageId, name: "FreshConflict",
+      outputDir: path.join(root, "downloads", "FreshConflict"), extractDir,
+      status: "queued", itemIds: ["fresh-pending"], cancelled: false, enabled: true,
+      createdAt: Date.now(), updatedAt: Date.now()
+    } as any;
+    session.items["fresh-pending"] = makeItem("fresh-pending", packageId, "queued", "fresh.rar");
+
+    const manager = new DownloadManager(
+      { ...defaultSettings(), token: "rd-token", outputDir: path.join(root, "downloads"), extractDir: path.join(root, "extract") },
+      session, storagePaths
+    );
+
+    const conflicts = await manager.getStartConflicts();
+    expect(conflicts.map((c) => c.packageId)).toContain(packageId);
+  });
+
+  it("start() holds excluded packages out of the run set and runs the rest", async () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "rd-selective-resume-"));
+    tempDirs.push(root);
+    const storagePaths = createStoragePaths(path.join(root, "state"));
+    initPackageLogs(storagePaths.baseDir);
+    initItemLogs(storagePaths.baseDir);
+
+    const session = emptySession();
+    const runId = "pkg-run";
+    const holdId = "pkg-hold";
+    fs.mkdirSync(path.join(root, "downloads", "RunMe"), { recursive: true });
+    fs.mkdirSync(path.join(root, "downloads", "HoldMe"), { recursive: true });
+    session.packageOrder = [runId, holdId];
+    session.packages[runId] = {
+      id: runId, name: "RunMe",
+      outputDir: path.join(root, "downloads", "RunMe"), extractDir: path.join(root, "extract", "RunMe"),
+      status: "queued", itemIds: ["run-item"], cancelled: false, enabled: true,
+      createdAt: Date.now(), updatedAt: Date.now()
+    } as any;
+    session.packages[holdId] = {
+      id: holdId, name: "HoldMe",
+      outputDir: path.join(root, "downloads", "HoldMe"), extractDir: path.join(root, "extract", "HoldMe"),
+      status: "queued", itemIds: ["hold-item"], cancelled: false, enabled: true,
+      createdAt: Date.now(), updatedAt: Date.now()
+    } as any;
+    session.items["run-item"] = makeItem("run-item", runId, "queued", "run.rar");
+    session.items["hold-item"] = makeItem("hold-item", holdId, "queued", "hold.rar");
+
+    const manager = new DownloadManager(
+      { ...defaultSettings(), token: "rd-token", maxParallel: 2, outputDir: path.join(root, "downloads"), extractDir: path.join(root, "extract") },
+      session, storagePaths
+    );
+    (manager as any).debridService.unrestrictLink = () => new Promise(() => {});
+
+    await manager.start({ excludePackageIds: new Set([holdId]) });
+
+    expect((manager as any).runPackageIds.has(runId)).toBe(true);
+    expect((manager as any).runPackageIds.has(holdId)).toBe(false);
+    expect((manager as any).runItemIds.has("run-item")).toBe(true);
+    expect((manager as any).runItemIds.has("hold-item")).toBe(false);
+    expect(session.items["hold-item"].status).toBe("queued");
+
+    manager.stop();
+  });
+});
+
+describe("mega-debrid api/web resolution overlap gate", () => {
+  function megaApiSettings(root: string): any {
+    return {
+      ...defaultSettings(),
+      megaLogin: "u", megaPassword: "p", megaCredentials: "u:p",
+      megaDebridApiEnabled: true, megaDebridWebEnabled: true, megaDebridPreferApi: true,
+      outputDir: path.join(root, "downloads"), extractDir: path.join(root, "extract")
+    };
+  }
+
+  function megaItem(id: string, status: string): any {
+    return {
+      id, packageId: "pkg", url: `https://rapidgator.net/file/${id}`, provider: "megadebrid-api",
+      status, retries: 0, speedBps: 0, downloadedBytes: 0, totalBytes: null, progressPercent: 0,
+      fileName: `${id}.rar`, targetPath: "", resumable: true, attempts: 0, lastError: "", fullStatus: "",
+      createdAt: Date.now(), updatedAt: Date.now()
+    };
+  }
+
+  function addValidating(manager: DownloadManager, session: any, ids: string[]): void {
+    for (const id of ids) {
+      session.items[id] = megaItem(id, "validating");
+      (manager as any).activeTasks.set(id, {
+        itemId: id, packageId: "pkg", abortController: new AbortController(), abortReason: "none",
+        resumable: true, nonResumableCounted: false, blockedOnDiskWrite: false, blockedOnDiskSince: 0
+      });
+    }
+  }
+
+  function buildManager(root: string, session: any): DownloadManager {
+    return new DownloadManager(megaApiSettings(root), session, createStoragePaths(path.join(root, "state")));
+  }
+
+  it("lets the first mega resolve start when nothing is in flight", () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "rd-overlap-0-"));
+    tempDirs.push(root);
+    const session = emptySession();
+    const candidate = megaItem("cand", "queued");
+    session.items["cand"] = candidate;
+    const manager = buildManager(root, session);
+    expect((manager as any).shouldDelayStartForItem(candidate)).toBe(false);
+  });
+
+  it("serializes a second API resolve while the first is still in its API phase (no concurrent API)", () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "rd-overlap-1-"));
+    tempDirs.push(root);
+    const session = emptySession();
+    const candidate = megaItem("cand", "queued");
+    session.items["cand"] = candidate;
+    const manager = buildManager(root, session);
+    addValidating(manager, session, ["a"]);
+    expect((manager as any).shouldDelayStartForItem(candidate)).toBe(true);
+  });
+
+  it("allows one API resolve to overlap once the first has moved to its web phase", () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "rd-overlap-2-"));
+    tempDirs.push(root);
+    const session = emptySession();
+    const candidate = megaItem("cand", "queued");
+    session.items["cand"] = candidate;
+    const manager = buildManager(root, session);
+    addValidating(manager, session, ["a"]);
+    primeMegaDebridInFlightForTests("acc:web", 1);
+    expect((manager as any).shouldDelayStartForItem(candidate)).toBe(false);
+  });
+
+  it("caps the overlap at one API plus one web (no third concurrent resolve)", () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "rd-overlap-3-"));
+    tempDirs.push(root);
+    const session = emptySession();
+    const candidate = megaItem("cand", "queued");
+    session.items["cand"] = candidate;
+    const manager = buildManager(root, session);
+    addValidating(manager, session, ["a", "b"]);
+    primeMegaDebridInFlightForTests("acc:web", 1);
+    expect((manager as any).shouldDelayStartForItem(candidate)).toBe(true);
+  });
+});
--- a/tests/session-restart-loss.test.ts
+++ b/tests/session-restart-loss.test.ts
--- a/tests/unrestrict-retry.test.ts
+++ b/tests/unrestrict-retry.test.ts
@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { transientResolveRetryDelayMs, parseMegaDebridCooldownRetry, parseMegaDebridResetPark } from "../src/main/download-manager";
+import { transientResolveRetryDelayMs, parseMegaDebridCooldownRetry, parseMegaDebridResetPark, parseMegaDebridSlowLinkRetry } from "../src/main/download-manager";

 describe("transientResolveRetryDelayMs (fast, bounded retry for transient resolve failures)", () => {
  it("starts fast (<= 3s) instead of the 5s..120s exponential", () => {
@ -63,6 +63,31 @@ describe("parseMegaDebridCooldownRetry (honor the encoded account-cooldown delay
  });
 });

+describe("parseMegaDebridSlowLinkRetry (park only the slow link, never the account)", () => {
+  it("parses the encoded delay from a slow-link error", () => {
+    const r = parseMegaDebridSlowLinkRetry("mega_debrid_slow_link:120000:Mega-Debrid (Account 1/1, Su******e3): aborted");
+    expect(r).not.toBeNull();
+    expect(r!.delayMs).toBe(120000);
+    expect(r!.detail).toContain("Mega-Debrid");
+  });
+
+  it("parses it when embedded in the aggregated provider-chain error", () => {
+    const aggregated = "Provider-Kette: Mega-Debrid Web fehlgeschlagen (Error: mega_debrid_slow_link:90000:Mega-Debrid (Account 1/1): aborted)";
+    expect(parseMegaDebridSlowLinkRetry(aggregated)!.delayMs).toBe(90000);
+  });
+
+  it("clamps to [1s, 15min]", () => {
+    expect(parseMegaDebridSlowLinkRetry("mega_debrid_slow_link:1:x")!.delayMs).toBe(1000);
+    expect(parseMegaDebridSlowLinkRetry("mega_debrid_slow_link:99999999:x")!.delayMs).toBe(15 * 60 * 1000);
+  });
+
+  it("does not collide with the account-cooldown or reset-park tokens", () => {
+    expect(parseMegaDebridSlowLinkRetry("mega_debrid_cooldown:20330:x")).toBeNull();
+    expect(parseMegaDebridSlowLinkRetry("mega_debrid_reset_park:43200000:x")).toBeNull();
+    expect(parseMegaDebridCooldownRetry("mega_debrid_slow_link:120000:x")).toBeNull();
+  });
+});
+
 describe("parseMegaDebridResetPark (park the item until the Tagesreset, not a ~2min generic retry)", () => {
  it("parses the encoded until-reset delay from the park token", () => {
    const r = parseMegaDebridResetPark("mega_debrid_reset_park:43200000:Mega-Debrid: Alle Accounts am Tageslimit (bis zum Tagesreset gesperrt)");
--- a/tools/rd-diagnostics-mcp/README.md
+++ b/tools/rd-diagnostics-mcp/README.md
@ -0,0 +1,62 @@
+# rd-diagnostics-mcp
+
+Standalone **stdio MCP bridge** to the Real-Debrid-Downloader debug-server. It runs on the machine where the
+MCP client runs, takes a **connection code** for a downloader server, and exposes that server's
+read-only HTTP diagnostics API (`/diagnostics`, `/status`, `/errors`, `/logs/*`, `/accounts`, …) as MCP tools.
+One bridge serves all 5–6 servers; you pass a `code` (or a configured `server` name) per call.
+
+This bridge is **not** bundled into the Electron app and adds **no** dependencies to it.
+
+## Setup
+
+```bash
+cd tools/rd-diagnostics-mcp
+npm install
+```
+
+Register it with your MCP client as a stdio server that launches the bridge:
+
+```bash
+node "<repo>/tools/rd-diagnostics-mcp/src/bridge.mjs"
+```
+
+Provide servers via environment variables (codes contain a token — treat like passwords):
+
+- `RDDIAG_CODE` — a single default connection code (`rddiag:v1:...`)
+- `RDDIAG_SERVERS` — JSON map of name → code, e.g. `{"berlin":"rddiag:v1:...","fra":"rddiag:v1:..."}`
+
+Without env config, every tool simply takes a `code` argument.
+
+## Tools
+
+`rd_servers`, `rd_ping`, `rd_diagnostics`, `rd_status`, `rd_items`, `rd_packages`, `rd_errors`, `rd_logs`
+(`main|audit|rename|trace|session|conversion|package|item`), `rd_history`, `rd_accounts`, `rd_providers`
+(live per-account/key cooldown + in-flight + rotation state), `rd_host`, `rd_self_check`,
+`rd_get` (raw escape-hatch, any read-only path).
+
+Each tool accepts `code` or `server` to pick the target.
+
+## Connection code
+
+Format: `rddiag:v1:<base64url(JSON)>` with `{ v:1, h:host, p:port, t:token, n?:name, fp?:certFingerprint, s?:scheme }`.
+Generated by the app (Hilfe → Remote-Support → Ferndiagnose (MCP)) or via `node src/gen-code.mjs --host H --port P --token T`.
+
+## Security model (read before exposing a server)
+
+- The debug surface is **read-only** for state/logs; the one control endpoint is `/trace/config` (toggles the
+  optional, time-bounded support trace). No persistent secrets are written into the logs it serves: passwords are
+  redacted, debrid API keys/tokens and resolved download URLs are never logged; `/settings` and `/accounts` are redacted.
+- Auth is a bearer token (24 random bytes). Over plain HTTP on a public network the token is sniffable, so:
+  - **Preferred:** keep the server bound to `127.0.0.1` ("Nur lokal") and reach it through a private tunnel
+    (Tailscale / SSH / Cloudflare Tunnel). The tunnel encrypts and authenticates; no public exposure.
+  - **Direct network bind (`0.0.0.0`)** requires a non-empty **IP allowlist** (enforced fail-closed: with an empty
+    allowlist only loopback is accepted). Use only inside a trusted LAN/VPN.
+- Revoke instantly from the app ("Token neu" or "Deaktivieren") — the old code stops working immediately.
+- `fp` pins a self-signed cert fingerprint and is verified on `secureConnect` (before the token is sent). HTTPS is
+  not the v1 default; plain HTTP behind a tunnel is the recommended transport.
+
+## Test
+
+```bash
+npm test    # spins a fake debug-server, runs the bridge as a stdio child, asserts the full protocol path
+```
--- a/tools/rd-diagnostics-mcp/package-lock.json
+++ b/tools/rd-diagnostics-mcp/package-lock.json
--- a/tools/rd-diagnostics-mcp/package.json
+++ b/tools/rd-diagnostics-mcp/package.json
@ -0,0 +1,18 @@
+{
+  "name": "rd-diagnostics-mcp",
+  "version": "1.0.0",
+  "private": true,
+  "description": "Standalone stdio MCP bridge to the Real-Debrid-Downloader debug-server. Connects via connection code, proxies the read-only HTTP diagnostics API as MCP tools.",
+  "type": "module",
+  "bin": {
+    "rd-diagnostics-mcp": "src/bridge.mjs"
+  },
+  "scripts": {
+    "start": "node src/bridge.mjs",
+    "test": "node test/harness.mjs"
+  },
+  "dependencies": {
+    "@modelcontextprotocol/sdk": "^1.12.0",
+    "zod": "^3.23.8"
+  }
+}
--- a/tools/rd-diagnostics-mcp/src/bridge.mjs
+++ b/tools/rd-diagnostics-mcp/src/bridge.mjs
@ -0,0 +1,332 @@
+#!/usr/bin/env node
+import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
+import { z } from "zod";
+import { decodeConnectionCode } from "./code.mjs";
+import { debugGet } from "./http.mjs";
+
+function loadServerMap() {
+  const map = new Map();
+  const raw = process.env.RDDIAG_SERVERS;
+  if (raw) {
+    try {
+      const parsed = JSON.parse(raw);
+      for (const [name, code] of Object.entries(parsed || {})) {
+        map.set(String(name), String(code));
+      }
+    } catch {
+      process.stderr.write("rd-diagnostics-mcp: RDDIAG_SERVERS ist kein gueltiges JSON, wird ignoriert\n");
+    }
+  }
+  return map;
+}
+
+const SERVER_MAP = loadServerMap();
+const DEFAULT_CODE = process.env.RDDIAG_CODE ? String(process.env.RDDIAG_CODE) : "";
+
+function listAvailableServers() {
+  const names = [...SERVER_MAP.keys()];
+  if (DEFAULT_CODE) names.push("(RDDIAG_CODE-Default)");
+  return names;
+}
+
+function resolveTarget(args) {
+  let code = "";
+  if (args && args.code) {
+    code = String(args.code);
+  } else if (args && args.server) {
+    const found = SERVER_MAP.get(String(args.server));
+    if (!found) {
+      throw new Error(
+        `Server "${args.server}" nicht konfiguriert. Bekannt: ${listAvailableServers().join(", ") || "(keine)"}`
+      );
+    }
+    code = found;
+  } else if (DEFAULT_CODE) {
+    code = DEFAULT_CODE;
+  } else if (SERVER_MAP.size === 1) {
+    code = [...SERVER_MAP.values()][0];
+  } else {
+    throw new Error(
+      `Kein Verbindungscode. Uebergib "code" oder "server", oder setze RDDIAG_CODE/RDDIAG_SERVERS. Bekannt: ${listAvailableServers().join(", ") || "(keine)"}`
+    );
+  }
+  return decodeConnectionCode(code);
+}
+
+function targetLabel(target) {
+  return target.name ? `${target.name} (${target.host}:${target.port})` : `${target.host}:${target.port}`;
+}
+
+function buildQuery(params) {
+  const usable = Object.entries(params || {}).filter(
+    ([, v]) => v !== undefined && v !== null && String(v).length > 0
+  );
+  if (usable.length === 0) return "";
+  const sp = new URLSearchParams();
+  for (const [k, v] of usable) sp.set(k, String(v));
+  return "?" + sp.toString();
+}
+
+function prettyBody(body) {
+  try {
+    return JSON.stringify(JSON.parse(body), null, 2);
+  } catch {
+    return body;
+  }
+}
+
+function connectionHint(err) {
+  const m = String((err && err.code) || err && err.message || "");
+  if (/ECONNREFUSED/.test(m)) return "Debug-Server nicht erreichbar — auf dem Server aktiviert? Port/Firewall offen?";
+  if (/ENOTFOUND|EAI_AGAIN/.test(m)) return "Host nicht aufloesbar — stimmt die Adresse im Verbindungscode?";
+  if (/ETIMEDOUT|Zeitueberschreitung/.test(m)) return "Zeitueberschreitung — Server/Netz langsam oder Port geblockt.";
+  if (/ECONNRESET|EPIPE/.test(m)) return "Verbindung abgebrochen — falscher Port/Scheme (http vs https)?";
+  if (/Fingerprint/.test(m)) return "TLS-Fingerprint passt nicht — Code stammt evtl. von einem anderen Server.";
+  return "";
+}
+
+async function requestTool(args, path, params, opts = {}) {
+  let target;
+  try {
+    target = resolveTarget(args);
+  } catch (err) {
+    return { content: [{ type: "text", text: `# Verbindungsfehler\n${err.message}` }], isError: true };
+  }
+  const fullPath = path + buildQuery(params);
+  const label = targetLabel(target);
+  try {
+    const res = await debugGet(target, fullPath, { timeoutMs: opts.timeoutMs || 20000 });
+    const isError = res.status < 200 || res.status >= 300;
+    let extra = "";
+    if (res.status === 401) extra = "\n(401 = Token im Verbindungscode ist abgelaufen/rotiert. Neuen Code anfordern.)";
+    if (res.status === 503) extra = "\n(503 = Download-Manager nicht bereit. App laeuft, aber noch nicht initialisiert?)";
+    const head = `# ${label} ${fullPath} → HTTP ${res.status}${extra}`;
+    return { content: [{ type: "text", text: head + "\n" + prettyBody(res.body) }], isError };
+  } catch (err) {
+    const hint = connectionHint(err);
+    const text = `# ${label} ${fullPath} → FEHLER\n${err.message}${hint ? "\n→ " + hint : ""}`;
+    return { content: [{ type: "text", text }], isError: true };
+  }
+}
+
+const CODE_FIELD = {
+  code: z.string().optional().describe("Verbindungscode (rddiag:v1:...). Optional, wenn server/RDDIAG_CODE gesetzt ist."),
+  server: z.string().optional().describe("Name eines via RDDIAG_SERVERS konfigurierten Servers statt eines vollen Codes.")
+};
+
+const server = new McpServer({ name: "rd-diagnostics-mcp", version: "1.0.0" });
+
+server.registerTool(
+  "rd_servers",
+  {
+    title: "Konfigurierte Server",
+    description: "Listet die in dieser Bridge konfigurierten Server (RDDIAG_SERVERS / RDDIAG_CODE). Verbindet sich nicht.",
+    inputSchema: {}
+  },
+  async () => {
+    const names = [...SERVER_MAP.keys()];
+    const lines = [];
+    lines.push(`Konfigurierte Server: ${names.length}`);
+    for (const n of names) lines.push(`- ${n}`);
+    lines.push(`Default (RDDIAG_CODE): ${DEFAULT_CODE ? "gesetzt" : "nicht gesetzt"}`);
+    lines.push("");
+    lines.push("Tools akzeptieren entweder code:<rddiag:v1:...> oder server:<name>.");
+    return { content: [{ type: "text", text: lines.join("\n") }] };
+  }
+);
+
+server.registerTool(
+  "rd_ping",
+  {
+    title: "Erreichbarkeit pruefen",
+    description: "Schneller Health-Check (GET /health): App-Version, Uptime, Speicher. Zuerst aufrufen, um Erreichbarkeit + Token zu pruefen.",
+    inputSchema: { ...CODE_FIELD }
+  },
+  async (args) => requestTool(args, "/health", {}, { timeoutMs: 10000 })
+);
+
+server.registerTool(
+  "rd_diagnostics",
+  {
+    title: "Gesamtdiagnose",
+    description: "Aggregierter Zustand (GET /diagnostics): Meta, Status, Settings, Stats, Accounts, History, Host + die wichtigsten Logs. Der 'alles auf einen Blick'-Endpunkt.",
+    inputSchema: {
+      ...CODE_FIELD,
+      lines: z.number().int().positive().optional().describe("Anzahl Log-Zeilen pro Log (Default 150)."),
+      grep: z.string().optional().describe("Filter fuer Log-Zeilen."),
+      package: z.string().optional().describe("Optional auf ein Paket fokussieren.")
+    }
+  },
+  async (args) => requestTool(args, "/diagnostics", { lines: args.lines, grep: args.grep, package: args.package }, { timeoutMs: 30000 })
+);
+
+server.registerTool(
+  "rd_status",
+  {
+    title: "Live-Status",
+    description: "Laufzeit-Status (GET /status): aktive Downloads, Queue, Provider-Zustand.",
+    inputSchema: { ...CODE_FIELD }
+  },
+  async (args) => requestTool(args, "/status", {})
+);
+
+server.registerTool(
+  "rd_items",
+  {
+    title: "Download-Items",
+    description: "Einzelne Download-Items (GET /items), optional gefiltert nach Status/Paket.",
+    inputSchema: {
+      ...CODE_FIELD,
+      status: z.string().optional().describe("Status-Filter (z.B. downloading, error, done)."),
+      package: z.string().optional().describe("Paket-Filter.")
+    }
+  },
+  async (args) => requestTool(args, "/items", { status: args.status, package: args.package })
+);
+
+server.registerTool(
+  "rd_packages",
+  {
+    title: "Pakete",
+    description: "Pakete (GET /packages), optional mit enthaltenen Items.",
+    inputSchema: {
+      ...CODE_FIELD,
+      package: z.string().optional().describe("Bestimmtes Paket."),
+      includeItems: z.boolean().optional().describe("Items mitliefern.")
+    }
+  },
+  async (args) => requestTool(args, "/packages", { package: args.package, includeItems: args.includeItems ? "1" : "" })
+);
+
+server.registerTool(
+  "rd_errors",
+  {
+    title: "Letzte Fehler",
+    description: "Fehler-Ring (GET /errors): die letzten Fehler mit Level/Quelle. 'Was ist schiefgelaufen'.",
+    inputSchema: {
+      ...CODE_FIELD,
+      level: z.string().optional().describe("Level-Filter (ERROR, WARN, ...)."),
+      limit: z.number().int().positive().optional().describe("Anzahl (Default 100).")
+    }
+  },
+  async (args) => requestTool(args, "/errors", { level: args.level, limit: args.limit })
+);
+
+const LOG_PATHS = {
+  main: "/logs/main",
+  audit: "/logs/audit",
+  rename: "/logs/rename",
+  trace: "/logs/trace",
+  session: "/logs/session",
+  conversion: "/logs/conversion",
+  package: "/logs/package",
+  item: "/logs/item"
+};
+
+server.registerTool(
+  "rd_logs",
+  {
+    title: "Log lesen",
+    description: "Liest das Ende eines Logs (GET /logs/<name>). name: main|audit|rename|trace|session|conversion|package|item. conversion = Pro-Item Link-Aufloesungs-Lebenszyklus (Token, API, Web, Rotation, Abbrueche mit Zeiten). Fuer package/item zusaetzlich package/item angeben.",
+    inputSchema: {
+      ...CODE_FIELD,
+      name: z.enum(["main", "audit", "rename", "trace", "session", "conversion", "package", "item"]).describe("Welches Log."),
+      lines: z.number().int().positive().optional().describe("Anzahl Zeilen vom Ende (Default 100)."),
+      grep: z.string().optional().describe("Filter."),
+      package: z.string().optional().describe("Nur fuer name=package."),
+      item: z.string().optional().describe("Nur fuer name=item.")
+    }
+  },
+  async (args) => {
+    const path = LOG_PATHS[args.name];
+    return requestTool(args, path, { lines: args.lines, grep: args.grep, package: args.package, item: args.item });
+  }
+);
+
+server.registerTool(
+  "rd_history",
+  {
+    title: "Verlauf",
+    description: "Abgeschlossener Verlauf (GET /history), optional nach Status/Suchbegriff.",
+    inputSchema: {
+      ...CODE_FIELD,
+      limit: z.number().int().positive().optional().describe("Anzahl (Default 50)."),
+      status: z.string().optional().describe("Status-Filter."),
+      grep: z.string().optional().describe("Suchbegriff.")
+    }
+  },
+  async (args) => requestTool(args, "/history", { limit: args.limit, status: args.status, grep: args.grep })
+);
+
+server.registerTool(
+  "rd_accounts",
+  {
+    title: "Accounts",
+    description: "Debrid-Accounts (GET /accounts, Token redigiert): Gueltigkeit, Premium, Cooldown/Rotation.",
+    inputSchema: { ...CODE_FIELD }
+  },
+  async (args) => requestTool(args, "/accounts", {})
+);
+
+server.registerTool(
+  "rd_providers",
+  {
+    title: "Provider-Laufzeitzustand",
+    description: "Live Provider-Runtime (GET /providers): pro Mega-Account/Debrid-Link-Key der AKTIVE Cooldown (until/remainingMs/Grund/Kategorie), in-flight-Tiefe, Mega-Rotationscursor, Empty-Response-Streaks. Die 'warum kuehlt es JETZT ab'-Ansicht — beantwortet Cooldown-Fragen direkt statt aus Log-Arithmetik.",
+    inputSchema: { ...CODE_FIELD }
+  },
+  async (args) => requestTool(args, "/providers", {})
+);
+
+server.registerTool(
+  "rd_host",
+  {
+    title: "Host-Diagnose",
+    description: "Windows-Host-Diagnose (GET /host/diagnostics): Laufwerke, Speicher, Pfade.",
+    inputSchema: { ...CODE_FIELD }
+  },
+  async (args) => requestTool(args, "/host/diagnostics", {})
+);
+
+server.registerTool(
+  "rd_self_check",
+  {
+    title: "Self-Check",
+    description: "Setup/Self-Check (GET /self-check): erkennt Konfigurations-/Pfadprobleme.",
+    inputSchema: { ...CODE_FIELD }
+  },
+  async (args) => requestTool(args, "/self-check", {})
+);
+
+server.registerTool(
+  "rd_get",
+  {
+    title: "Roh-Endpunkt (Escape-Hatch)",
+    description: "Beliebigen Debug-Server-Pfad lesen (GET <path>), wenn kein spezialisiertes Tool passt. Pfad inkl. fuehrendem / und optionalem Query-String, z.B. /meta oder /stats.",
+    inputSchema: {
+      ...CODE_FIELD,
+      path: z.string().describe("Pfad mit fuehrendem /, optional ?query. Nur GET, read-only.")
+    }
+  },
+  async (args) => {
+    const p = String(args.path || "");
+    if (!p.startsWith("/")) {
+      return { content: [{ type: "text", text: "# Fehler\npath muss mit / beginnen" }], isError: true };
+    }
+    return requestTool(args, p, {}, { timeoutMs: 30000 });
+  }
+);
+
+async function main() {
+  const transport = new StdioServerTransport();
+  await server.connect(transport);
+  process.stderr.write(
+    `rd-diagnostics-mcp bereit. Server: ${listAvailableServers().join(", ") || "(keine vorkonfiguriert; code pro Aufruf uebergeben)"}\n`
+  );
+}
+
+main().catch((err) => {
+  process.stderr.write(`rd-diagnostics-mcp Startfehler: ${err && err.stack ? err.stack : err}\n`);
+  process.exit(1);
+});
--- a/tools/rd-diagnostics-mcp/src/code.d.mts
+++ b/tools/rd-diagnostics-mcp/src/code.d.mts
@ -0,0 +1,20 @@
+export interface DecodedConnectionCode {
+  host: string;
+  port: number;
+  token: string;
+  scheme: string;
+  name: string;
+  fingerprint: string;
+}
+
+export interface EncodeConnectionCodeInput {
+  host: string;
+  port: number;
+  token: string;
+  name?: string;
+  fingerprint?: string;
+  scheme?: string;
+}
+
+export function encodeConnectionCode(input: EncodeConnectionCodeInput): string;
+export function decodeConnectionCode(code: string): DecodedConnectionCode;
--- a/tools/rd-diagnostics-mcp/src/code.mjs
+++ b/tools/rd-diagnostics-mcp/src/code.mjs
@ -0,0 +1,56 @@
+const PREFIX = "rddiag:v1:";
+
+function base64urlEncode(str) {
+  return Buffer.from(str, "utf8")
+    .toString("base64")
+    .replace(/\+/g, "-")
+    .replace(/\//g, "_")
+    .replace(/=+$/, "");
+}
+
+function base64urlDecode(str) {
+  const pad = str.length % 4 === 0 ? "" : "=".repeat(4 - (str.length % 4));
+  const b64 = str.replace(/-/g, "+").replace(/_/g, "/") + pad;
+  return Buffer.from(b64, "base64").toString("utf8");
+}
+
+export function encodeConnectionCode({ host, port, token, name, fingerprint, scheme }) {
+  if (!host || typeof host !== "string") throw new Error("host fehlt");
+  const p = Number(port);
+  if (!Number.isInteger(p) || p < 1 || p > 65535) throw new Error("port ungueltig");
+  if (!token || typeof token !== "string") throw new Error("token fehlt");
+  const payload = { v: 1, h: host, p, t: token };
+  if (name) payload.n = String(name);
+  if (fingerprint) payload.fp = String(fingerprint);
+  if (scheme && scheme !== "http") payload.s = String(scheme);
+  return PREFIX + base64urlEncode(JSON.stringify(payload));
+}
+
+export function decodeConnectionCode(code) {
+  const raw = String(code || "").trim();
+  if (!raw.startsWith(PREFIX)) {
+    throw new Error(`Verbindungscode muss mit "${PREFIX}" beginnen`);
+  }
+  let json;
+  try {
+    json = JSON.parse(base64urlDecode(raw.slice(PREFIX.length)));
+  } catch {
+    throw new Error("Verbindungscode ist beschaedigt (kein gueltiges base64url/JSON)");
+  }
+  if (!json || typeof json !== "object") throw new Error("Verbindungscode-Inhalt ungueltig");
+  const host = String(json.h || "").trim();
+  const port = Number(json.p);
+  const token = String(json.t || "");
+  if (!host) throw new Error("Verbindungscode ohne Host");
+  if (!Number.isInteger(port) || port < 1 || port > 65535) throw new Error("Verbindungscode mit ungueltigem Port");
+  if (!token) throw new Error("Verbindungscode ohne Token");
+  const scheme = json.s === "https" ? "https" : "http";
+  return {
+    host,
+    port,
+    token,
+    scheme,
+    name: json.n ? String(json.n) : "",
+    fingerprint: json.fp ? String(json.fp) : ""
+  };
+}
--- a/tools/rd-diagnostics-mcp/src/gen-code.mjs
+++ b/tools/rd-diagnostics-mcp/src/gen-code.mjs
@ -0,0 +1,22 @@
+#!/usr/bin/env node
+import { encodeConnectionCode } from "./code.mjs";
+
+function arg(name, fallback) {
+  const i = process.argv.indexOf("--" + name);
+  if (i >= 0 && i + 1 < process.argv.length) return process.argv[i + 1];
+  return fallback;
+}
+
+const host = arg("host");
+const port = arg("port");
+const token = arg("token");
+const name = arg("name");
+const scheme = arg("scheme");
+const fingerprint = arg("fp");
+
+if (!host || !port || !token) {
+  process.stderr.write("Usage: node src/gen-code.mjs --host <h> --port <p> --token <t> [--name <n>] [--scheme https] [--fp <sha256>]\n");
+  process.exit(2);
+}
+
+process.stdout.write(encodeConnectionCode({ host, port, token, name, scheme, fingerprint }) + "\n");
--- a/tools/rd-diagnostics-mcp/src/http.mjs
+++ b/tools/rd-diagnostics-mcp/src/http.mjs
@ -0,0 +1,63 @@
+import http from "node:http";
+import https from "node:https";
+
+function normalizeFp(fp) {
+  return String(fp || "").replace(/:/g, "").toLowerCase();
+}
+
+export function debugGet(target, path, { timeoutMs = 20000 } = {}) {
+  const scheme = target.scheme === "https" ? "https" : "http";
+  const lib = scheme === "https" ? https : http;
+  const rel = path.startsWith("/") ? path : "/" + path;
+  const url = new URL(rel, `${scheme}://${target.host}:${target.port}`);
+  const pinning = scheme === "https" && !!target.fingerprint;
+
+  return new Promise((resolve, reject) => {
+    const options = {
+      method: "GET",
+      headers: {
+        Authorization: `Bearer ${target.token}`,
+        Accept: "application/json"
+      },
+      timeout: timeoutMs
+    };
+    if (scheme === "https") {
+      options.rejectUnauthorized = !target.fingerprint;
+    }
+
+    const req = lib.request(url, options, (res) => {
+      let data = "";
+      res.setEncoding("utf8");
+      res.on("data", (chunk) => {
+        data += chunk;
+      });
+      res.on("end", () => {
+        resolve({ status: res.statusCode || 0, body: data, headers: res.headers });
+      });
+    });
+
+    req.on("timeout", () => {
+      req.destroy(new Error(`Zeitueberschreitung nach ${timeoutMs}ms`));
+    });
+    req.on("error", (err) => {
+      reject(err);
+    });
+
+    if (pinning) {
+      req.on("socket", (socket) => {
+        socket.on("secureConnect", () => {
+          const cert = typeof socket.getPeerCertificate === "function" ? socket.getPeerCertificate() : null;
+          const got = normalizeFp(cert && cert.fingerprint256);
+          const want = normalizeFp(target.fingerprint);
+          if (!got || got !== want) {
+            req.destroy(new Error(`TLS-Fingerprint stimmt nicht (erwartet ${want || "?"}, erhalten ${got || "?"})`));
+            return;
+          }
+          req.end();
+        });
+      });
+    } else {
+      req.end();
+    }
+  });
+}
--- a/tools/rd-diagnostics-mcp/test/harness.mjs
+++ b/tools/rd-diagnostics-mcp/test/harness.mjs
@ -0,0 +1,175 @@
+import http from "node:http";
+import { spawn } from "node:child_process";
+import { fileURLToPath } from "node:url";
+import { dirname, join } from "node:path";
+import { encodeConnectionCode } from "../src/code.mjs";
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const BRIDGE = join(__dirname, "..", "src", "bridge.mjs");
+const TOKEN = "test-token-abc123";
+
+const failures = [];
+function check(name, cond, detail) {
+  if (cond) {
+    process.stdout.write(`  PASS ${name}\n`);
+  } else {
+    failures.push(name);
+    process.stdout.write(`  FAIL ${name}${detail ? " — " + detail : ""}\n`);
+  }
+}
+
+function startFakeServer() {
+  return new Promise((resolve) => {
+    const server = http.createServer((req, res) => {
+      const url = new URL(req.url, "http://localhost");
+      const auth = req.headers.authorization || "";
+      const tokenOk = auth === `Bearer ${TOKEN}` || url.searchParams.get("token") === TOKEN;
+      if (!tokenOk) {
+        res.writeHead(401, { "content-type": "application/json" });
+        res.end(JSON.stringify({ error: "Unauthorized" }));
+        return;
+      }
+      const p = url.pathname;
+      const q = Object.fromEntries(url.searchParams.entries());
+      const send = (obj) => {
+        res.writeHead(200, { "content-type": "application/json" });
+        res.end(JSON.stringify(obj));
+      };
+      if (p === "/health") return send({ status: "ok", appVersion: "1.7.222", uptime: 42 });
+      if (p === "/diagnostics") return send({ meta: { appVersion: "1.7.222" }, status: { active: 1 }, query: q });
+      if (p === "/errors") return send({ errors: [{ level: "ERROR", message: "boom" }], query: q });
+      if (p === "/logs/main") return send({ lines: ["line1", "line2"], count: 2, query: q });
+      if (p === "/status") return send({ active: 1, queued: 3 });
+      if (p === "/items") return send({ items: [], query: q });
+      if (p === "/accounts") return send({ accounts: [{ name: "acc1", premium: true }] });
+      if (p === "/meta") return send({ appVersion: "1.7.222", endpoints: ["/health", "/diagnostics"] });
+      res.writeHead(404, { "content-type": "application/json" });
+      res.end(JSON.stringify({ error: "not found", path: p }));
+    });
+    server.listen(0, "127.0.0.1", () => resolve(server));
+  });
+}
+
+function startBridge() {
+  const child = spawn(process.execPath, [BRIDGE], { stdio: ["pipe", "pipe", "pipe"] });
+  child.stderr.on("data", (d) => process.stderr.write(`[bridge] ${d}`));
+  const pending = new Map();
+  let buf = "";
+  child.stdout.on("data", (chunk) => {
+    buf += chunk.toString("utf8");
+    let idx;
+    while ((idx = buf.indexOf("\n")) >= 0) {
+      const line = buf.slice(0, idx).trim();
+      buf = buf.slice(idx + 1);
+      if (!line) continue;
+      let msg;
+      try {
+        msg = JSON.parse(line);
+      } catch {
+        continue;
+      }
+      if (msg.id !== undefined && pending.has(msg.id)) {
+        pending.get(msg.id)(msg);
+        pending.delete(msg.id);
+      }
+    }
+  });
+  let nextId = 1;
+  function rpc(method, params) {
+    const id = nextId++;
+    return new Promise((resolve, reject) => {
+      pending.set(id, resolve);
+      child.stdin.write(JSON.stringify({ jsonrpc: "2.0", id, method, params }) + "\n");
+      setTimeout(() => {
+        if (pending.has(id)) {
+          pending.delete(id);
+          reject(new Error(`RPC timeout: ${method}`));
+        }
+      }, 15000);
+    });
+  }
+  function notify(method, params) {
+    child.stdin.write(JSON.stringify({ jsonrpc: "2.0", method, params }) + "\n");
+  }
+  return { child, rpc, notify };
+}
+
+function textOf(callResult) {
+  const c = callResult && callResult.result && callResult.result.content;
+  if (!Array.isArray(c)) return "";
+  return c.map((x) => x.text || "").join("\n");
+}
+
+async function run() {
+  const fake = await startFakeServer();
+  const port = fake.address().port;
+  const code = encodeConnectionCode({ host: "127.0.0.1", port, token: TOKEN, name: "testserver" });
+  const badCode = encodeConnectionCode({ host: "127.0.0.1", port, token: "WRONG", name: "testserver" });
+
+  const bridge = startBridge();
+  try {
+    const init = await bridge.rpc("initialize", {
+      protocolVersion: "2024-11-05",
+      capabilities: {},
+      clientInfo: { name: "harness", version: "1.0.0" }
+    });
+    check("initialize handshake", !!(init.result && init.result.serverInfo), JSON.stringify(init.error || {}));
+    check("server name reported", init.result && init.result.serverInfo && init.result.serverInfo.name === "rd-diagnostics-mcp");
+    bridge.notify("notifications/initialized", {});
+
+    const tools = await bridge.rpc("tools/list", {});
+    const names = (tools.result && tools.result.tools || []).map((t) => t.name);
+    check("tools/list returns tools", names.length >= 10, `got ${names.length}`);
+    for (const expected of ["rd_ping", "rd_diagnostics", "rd_errors", "rd_logs", "rd_get", "rd_servers"]) {
+      check(`tool present: ${expected}`, names.includes(expected));
+    }
+
+    const ping = await bridge.rpc("tools/call", { name: "rd_ping", arguments: { code } });
+    const pingText = textOf(ping);
+    check("rd_ping reaches server", /HTTP 200/.test(pingText) && /"status": "ok"/.test(pingText), pingText.slice(0, 200));
+    check("rd_ping shows server label", /testserver \(127\.0\.0\.1:/.test(pingText));
+
+    const diag = await bridge.rpc("tools/call", { name: "rd_diagnostics", arguments: { code, lines: 50, grep: "err" } });
+    const diagText = textOf(diag);
+    check("rd_diagnostics returns aggregate", /"appVersion": "1\.7\.222"/.test(diagText));
+    check("rd_diagnostics passes query params", /"lines": "50"/.test(diagText) && /"grep": "err"/.test(diagText), diagText.slice(0, 300));
+
+    const logs = await bridge.rpc("tools/call", { name: "rd_logs", arguments: { code, name: "main", lines: 5 } });
+    const logsText = textOf(logs);
+    check("rd_logs maps name→path + lines", /logs\/main\?lines=5/.test(logsText) && /"count": 2/.test(logsText), logsText.slice(0, 200));
+
+    const errs = await bridge.rpc("tools/call", { name: "rd_errors", arguments: { code, level: "ERROR" } });
+    check("rd_errors returns ring", /"message": "boom"/.test(textOf(errs)));
+
+    const raw = await bridge.rpc("tools/call", { name: "rd_get", arguments: { code, path: "/meta" } });
+    check("rd_get escape hatch hits arbitrary path", /"endpoints"/.test(textOf(raw)));
+
+    const unauthorized = await bridge.rpc("tools/call", { name: "rd_ping", arguments: { code: badCode } });
+    check("bad token → HTTP 401 + isError", /HTTP 401/.test(textOf(unauthorized)) && unauthorized.result.isError === true);
+
+    const noCode = await bridge.rpc("tools/call", { name: "rd_ping", arguments: {} });
+    check("missing code → graceful isError", noCode.result && noCode.result.isError === true && /Kein Verbindungscode/.test(textOf(noCode)));
+
+    const unreachable = await bridge.rpc("tools/call", {
+      name: "rd_ping",
+      arguments: { code: encodeConnectionCode({ host: "127.0.0.1", port: 1, token: TOKEN }) }
+    });
+    check("unreachable → isError + hint", unreachable.result.isError === true && /nicht erreichbar|abgebrochen|FEHLER/.test(textOf(unreachable)), textOf(unreachable).slice(0, 160));
+  } finally {
+    bridge.child.kill();
+    fake.close();
+  }
+
+  process.stdout.write("\n");
+  if (failures.length) {
+    process.stdout.write(`RESULT: ${failures.length} FAIL\n`);
+    process.exit(1);
+  }
+  process.stdout.write("RESULT: ALL PASS\n");
+  process.exit(0);
+}
+
+run().catch((err) => {
+  process.stderr.write(`harness error: ${err && err.stack ? err.stack : err}\n`);
+  process.exit(1);
+});