diff --git a/CHANGELOG.md b/CHANGELOG.md
index d09e96dcec..6bc2d423b6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -23,6 +23,7 @@ Docs: https://docs.openclaw.ai
 - Scripts/UI/Windows: fix `pnpm ui:*` spawn `EINVAL` failures by restoring shell-backed launch for `.cmd`/`.bat` runners, narrowing shell usage to launcher types that require it, and rejecting unsafe forwarded shell metacharacters in UI script args. (#18594)
 - Hooks/Session-memory: recover `/new` conversation summaries when session pointers are reset-path or missing `sessionFile`, and consistently prefer the newest `.jsonl.reset.*` transcript candidate for fallback extraction. (#18088)
 - Slack: restrict forwarded-attachment ingestion to explicit shared-message attachments and skip non-Slack forwarded `image_url` fetches, preventing non-forward attachment unfurls from polluting inbound agent context while preserving forwarded message handling.
+- Agents/Sessions: align session lock watchdog hold windows with run and compaction timeout budgets (plus grace), preventing valid long-running turns from being force-unlocked mid-run while still recovering hung lock owners. (#18060)
 - Cron/Heartbeat: canonicalize session-scoped reminder `sessionKey` routing and preserve explicit flat `sessionKey` cron tool inputs, preventing enqueue/wake namespace drift for session-targeted reminders. (#18637) Thanks @vignesh07.
 - OpenClawKit/iOS ChatUI: accept canonical session-key completion events for local pending runs and preserve message IDs across history refreshes, preventing stuck "thinking" state and message flicker after gateway replies. (#18165) Thanks @mbelinky.
 - iOS/Onboarding: add QR-first onboarding wizard with setup-code deep link support, pairing/auth issue guidance, and device-pair QR generation improvements for Telegram/Web/TUI fallback flows. (#18162) Thanks @mbelinky and @Marvae.
diff --git a/src/agents/pi-embedded-runner/compact.ts b/src/agents/pi-embedded-runner/compact.ts
index 25917e9595..7d2f8815c7 100644
--- a/src/agents/pi-embedded-runner/compact.ts
+++ b/src/agents/pi-embedded-runner/compact.ts
@@ -1,5 +1,3 @@
-import fs from "node:fs/promises";
-import os from "node:os";
 import type { AgentMessage } from "@mariozechner/pi-agent-core";
 import {
   createAgentSession,
@@ -7,10 +5,14 @@ import {
   SessionManager,
   SettingsManager,
 } from "@mariozechner/pi-coding-agent";
-import { resolveHeartbeatPrompt } from "../../auto-reply/heartbeat.js";
+import fs from "node:fs/promises";
+import os from "node:os";
 import type { ReasoningLevel, ThinkLevel } from "../../auto-reply/thinking.js";
-import { resolveChannelCapabilities } from "../../config/channel-capabilities.js";
 import type { OpenClawConfig } from "../../config/config.js";
+import type { ExecElevatedDefaults } from "../bash-tools.js";
+import type { EmbeddedPiCompactResult } from "./types.js";
+import { resolveHeartbeatPrompt } from "../../auto-reply/heartbeat.js";
+import { resolveChannelCapabilities } from "../../config/channel-capabilities.js";
 import { getMachineDisplayName } from "../../infra/machine-name.js";
 import { getGlobalHookRunner } from "../../plugins/hook-runner-global.js";
 import { type enqueueCommand, enqueueCommandInLane } from "../../process/command-queue.js";
@@ -24,7 +26,6 @@ import { normalizeMessageChannel } from "../../utils/message-channel.js";
 import { isReasoningTagProvider } from "../../utils/provider-utils.js";
 import { resolveOpenClawAgentDir } from "../agent-paths.js";
 import { resolveSessionAgentIds } from "../agent-scope.js";
-import type { ExecElevatedDefaults } from "../bash-tools.js";
 import { makeBootstrapWarn, resolveBootstrapContextForRun } from "../bootstrap-files.js";
 import { listChannelSupportedActions, resolveChannelMessageToolHints } from "../channel-tools.js";
 import { formatUserTime, resolveUserTimeFormat, resolveUserTimezone } from "../date-time.js";
@@ -46,7 +47,10 @@ import { resolveSandboxContext } from "../sandbox.js";
 import { repairSessionFileIfNeeded } from "../session-file-repair.js";
 import { guardSessionManager } from "../session-tool-result-guard-wrapper.js";
 import { sanitizeToolUseResultPairing } from "../session-transcript-repair.js";
-import { acquireSessionWriteLock } from "../session-write-lock.js";
+import {
+  acquireSessionWriteLock,
+  resolveSessionLockMaxHoldFromTimeout,
+} from "../session-write-lock.js";
 import { detectRuntimeShell } from "../shell-utils.js";
 import {
   applySkillEnvOverrides,
@@ -56,7 +60,10 @@ import {
   type SkillSnapshot,
 } from "../skills.js";
 import { resolveTranscriptPolicy } from "../transcript-policy.js";
-import { compactWithSafetyTimeout } from "./compaction-safety-timeout.js";
+import {
+  compactWithSafetyTimeout,
+  EMBEDDED_COMPACTION_TIMEOUT_MS,
+} from "./compaction-safety-timeout.js";
 import { buildEmbeddedExtensionPaths } from "./extensions.js";
 import {
   logToolSchemasForGoogle,
@@ -75,7 +82,6 @@ import {
   createSystemPromptOverride,
 } from "./system-prompt.js";
 import { splitSdkTools } from "./tool-split.js";
-import type { EmbeddedPiCompactResult } from "./types.js";
 import { describeUnknownError, mapThinkingLevel } from "./utils.js";
 import { flushPendingToolResultsAfterIdle } from "./wait-for-idle-before-flush.js";
 
@@ -503,6 +509,9 @@ export async function compactEmbeddedPiSessionDirect(
 
     const sessionLock = await acquireSessionWriteLock({
       sessionFile: params.sessionFile,
+      maxHoldMs: resolveSessionLockMaxHoldFromTimeout({
+        timeoutMs: EMBEDDED_COMPACTION_TIMEOUT_MS,
+      }),
     });
     try {
       await repairSessionFileIfNeeded({
diff --git a/src/agents/pi-embedded-runner/run/attempt.ts b/src/agents/pi-embedded-runner/run/attempt.ts
index 2b71041c44..e70aeb0e67 100644
--- a/src/agents/pi-embedded-runner/run/attempt.ts
+++ b/src/agents/pi-embedded-runner/run/attempt.ts
@@ -1,9 +1,10 @@
-import fs from "node:fs/promises";
-import os from "node:os";
 import type { AgentMessage } from "@mariozechner/pi-agent-core";
 import type { ImageContent } from "@mariozechner/pi-ai";
 import { streamSimple } from "@mariozechner/pi-ai";
 import { createAgentSession, SessionManager, SettingsManager } from "@mariozechner/pi-coding-agent";
+import fs from "node:fs/promises";
+import os from "node:os";
+import type { EmbeddedRunAttemptParams, EmbeddedRunAttemptResult } from "./types.js";
 import { resolveHeartbeatPrompt } from "../../../auto-reply/heartbeat.js";
 import { resolveChannelCapabilities } from "../../../config/channel-capabilities.js";
 import { getMachineDisplayName } from "../../../infra/machine-name.js";
@@ -54,7 +55,10 @@ import { resolveSandboxRuntimeStatus } from "../../sandbox/runtime-status.js";
 import { repairSessionFileIfNeeded } from "../../session-file-repair.js";
 import { guardSessionManager } from "../../session-tool-result-guard-wrapper.js";
 import { sanitizeToolUseResultPairing } from "../../session-transcript-repair.js";
-import { acquireSessionWriteLock } from "../../session-write-lock.js";
+import {
+  acquireSessionWriteLock,
+  resolveSessionLockMaxHoldFromTimeout,
+} from "../../session-write-lock.js";
 import { detectRuntimeShell } from "../../shell-utils.js";
 import {
   applySkillEnvOverrides,
@@ -100,7 +104,6 @@ import {
   shouldFlagCompactionTimeout,
 } from "./compaction-timeout.js";
 import { detectAndLoadPromptImages } from "./images.js";
-import type { EmbeddedRunAttemptParams, EmbeddedRunAttemptResult } from "./types.js";
 
 export function injectHistoryImagesIntoMessages(
   messages: AgentMessage[],
@@ -482,6 +485,9 @@ export async function runEmbeddedAttempt(
 
     const sessionLock = await acquireSessionWriteLock({
       sessionFile: params.sessionFile,
+      maxHoldMs: resolveSessionLockMaxHoldFromTimeout({
+        timeoutMs: params.timeoutMs,
+      }),
     });
 
     let sessionManager: ReturnType<typeof guardSessionManager> | undefined;
diff --git a/src/agents/session-write-lock.e2e.test.ts b/src/agents/session-write-lock.e2e.test.ts
index 9d829ba5cb..12865204da 100644
--- a/src/agents/session-write-lock.e2e.test.ts
+++ b/src/agents/session-write-lock.e2e.test.ts
@@ -2,7 +2,12 @@ import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
 import { describe, expect, it, vi } from "vitest";
-import { __testing, acquireSessionWriteLock, cleanStaleLockFiles } from "./session-write-lock.js";
+import {
+  __testing,
+  acquireSessionWriteLock,
+  cleanStaleLockFiles,
+  resolveSessionLockMaxHoldFromTimeout,
+} from "./session-write-lock.js";
 
 describe("acquireSessionWriteLock", () => {
   it("reuses locks across symlinked session paths", async () => {
@@ -103,6 +108,19 @@ describe("acquireSessionWriteLock", () => {
     }
   });
 
+  it("derives max hold from timeout plus grace", () => {
+    expect(resolveSessionLockMaxHoldFromTimeout({ timeoutMs: 600_000 })).toBe(720_000);
+    expect(resolveSessionLockMaxHoldFromTimeout({ timeoutMs: 1_000, minMs: 5_000 })).toBe(123_000);
+  });
+
+  it("clamps max hold for effectively no-timeout runs", () => {
+    expect(
+      resolveSessionLockMaxHoldFromTimeout({
+        timeoutMs: 2_147_000_000,
+      }),
+    ).toBe(2_147_000_000);
+  });
+
   it("cleans stale .jsonl lock files in sessions directories", async () => {
     const root = await fs.mkdtemp(path.join(os.tmpdir(), "openclaw-lock-"));
     const sessionsDir = path.join(root, "sessions");
diff --git a/src/agents/session-write-lock.ts b/src/agents/session-write-lock.ts
index 7ae9ae1c33..847d5c7429 100644
--- a/src/agents/session-write-lock.ts
+++ b/src/agents/session-write-lock.ts
@@ -38,6 +38,8 @@ const WATCHDOG_STATE_KEY = Symbol.for("openclaw.sessionWriteLockWatchdogState");
 const DEFAULT_STALE_MS = 30 * 60 * 1000;
 const DEFAULT_MAX_HOLD_MS = 5 * 60 * 1000;
 const DEFAULT_WATCHDOG_INTERVAL_MS = 60_000;
+const DEFAULT_TIMEOUT_GRACE_MS = 2 * 60 * 1000;
+const MAX_LOCK_HOLD_MS = 2_147_000_000;
 
 type CleanupState = {
   registered: boolean;
@@ -95,6 +97,20 @@ function resolvePositiveMs(
   return value;
 }
 
+export function resolveSessionLockMaxHoldFromTimeout(params: {
+  timeoutMs: number;
+  graceMs?: number;
+  minMs?: number;
+}): number {
+  const minMs = resolvePositiveMs(params.minMs, DEFAULT_MAX_HOLD_MS);
+  const timeoutMs = resolvePositiveMs(params.timeoutMs, minMs, { allowInfinity: true });
+  if (timeoutMs === Number.POSITIVE_INFINITY) {
+    return MAX_LOCK_HOLD_MS;
+  }
+  const graceMs = resolvePositiveMs(params.graceMs, DEFAULT_TIMEOUT_GRACE_MS);
+  return Math.min(MAX_LOCK_HOLD_MS, Math.max(minMs, timeoutMs + graceMs));
+}
+
 async function releaseHeldLock(
   normalizedSessionFile: string,
   held: HeldLock,