diff --git a/CHANGELOG.md b/CHANGELOG.md
index bba162b1211..13ec95e3405 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -58,6 +58,7 @@ Docs: https://docs.openclaw.ai
 - Release/CI/E2E: fail the kitchen-sink RPC walk when command RSS sampling captures no process samples.
 - Release/CI/E2E: force-stop memory/fd repro gateway children that survive listener cleanup.
 - Release/CI/E2E: remove fallback ClawHub skill-install home directories when proof runs fail.
+- Release/CI/E2E: let plugin lifecycle measurement wrappers exit promptly after external shutdown while preserving descendant cleanup.
 - Installers: fail the PowerShell installer when interactive onboarding exits non-zero.
 - Scripts/UI: stop descendant processes from wrapped non-interactive commands when `run-with-env` receives shutdown signals.
 - Release/CI/E2E: write multi-node update Docker artifacts to unique per-run directories by default so parallel runs cannot overwrite evidence.
diff --git a/scripts/e2e/lib/plugin-lifecycle-matrix/measure.mjs b/scripts/e2e/lib/plugin-lifecycle-matrix/measure.mjs
index cf5b961a90d..4be88fdff9a 100644
--- a/scripts/e2e/lib/plugin-lifecycle-matrix/measure.mjs
+++ b/scripts/e2e/lib/plugin-lifecycle-matrix/measure.mjs
@@ -125,7 +125,10 @@ let maxCpuTicks = 0;
 let timedOut = false;
 let finished = false;
 let parentSignalInFlight = false;
+let forwardedParentSignal = null;
 let killTimer;
+let parentSignalTimer;
+let parentSignalPollTimer;
 const updateMetrics = () => {
   if (!child.pid) {
     return;
@@ -164,6 +167,21 @@ function terminateChildGroup(signal) {
   } catch {}
 }
 
+function childGroupExists() {
+  if (!child.pid) {
+    return false;
+  }
+  try {
+    process.kill(-child.pid, 0);
+    return true;
+  } catch (error) {
+    if (error && error.code === "ESRCH") {
+      return false;
+    }
+    return true;
+  }
+}
+
 function clearRuntimeTimers() {
   clearInterval(interval);
   if (timeoutTimer) {
@@ -172,9 +190,16 @@ function clearRuntimeTimers() {
   if (killTimer) {
     clearTimeout(killTimer);
   }
+  if (parentSignalTimer) {
+    clearTimeout(parentSignalTimer);
+  }
+  if (parentSignalPollTimer) {
+    clearInterval(parentSignalPollTimer);
+  }
 }
 
 function rethrowParentSignal(signal) {
+  clearRuntimeTimers();
   process.removeAllListeners(signal);
   process.kill(process.pid, signal);
   process.exit(128);
@@ -192,12 +217,18 @@ function handleParentSignal(signal) {
     return;
   }
   finished = true;
+  forwardedParentSignal = signal;
   clearRuntimeTimers();
   terminateChildGroup(signal);
-  setTimeout(() => {
+  parentSignalTimer = setTimeout(() => {
     terminateChildGroup("SIGKILL");
     rethrowParentSignal(signal);
   }, timeoutKillGraceMs);
+  parentSignalPollTimer = setInterval(() => {
+    if (!childGroupExists()) {
+      rethrowParentSignal(signal);
+    }
+  }, Math.min(50, timeoutKillGraceMs));
 }
 
 for (const signal of ["SIGHUP", "SIGINT", "SIGTERM"]) {
@@ -248,6 +279,12 @@ child.on("error", (error) => {
 });
 
 child.on("exit", (code, signal) => {
+  if (parentSignalInFlight && forwardedParentSignal) {
+    if (!childGroupExists()) {
+      rethrowParentSignal(forwardedParentSignal);
+    }
+    return;
+  }
   if (timedOut && killTimer) {
     return;
   }
diff --git a/test/scripts/plugin-lifecycle-measure.test.ts b/test/scripts/plugin-lifecycle-measure.test.ts
index 0aae4a1dc64..6dde1b0ca7e 100644
--- a/test/scripts/plugin-lifecycle-measure.test.ts
+++ b/test/scripts/plugin-lifecycle-measure.test.ts
@@ -1,5 +1,10 @@
-import { spawnSync } from "node:child_process";
-import { mkdtempSync, readFileSync, rmSync } from "node:fs";
+import { spawn, spawnSync, type ChildProcess } from "node:child_process";
+import {
+  existsSync,
+  mkdtempSync,
+  readFileSync,
+  rmSync,
+} from "node:fs";
 import { tmpdir } from "node:os";
 import path from "node:path";
 import { afterEach, describe, expect, it } from "vitest";
@@ -38,6 +43,35 @@ function waitForPidExit(pid: number, timeoutMs: number): boolean {
   return !pidExists(pid);
 }
 
+function waitForPath(filePath: string, timeoutMs: number): boolean {
+  const waitBuffer = new SharedArrayBuffer(4);
+  const waitView = new Int32Array(waitBuffer);
+  const deadline = Date.now() + timeoutMs;
+  while (Date.now() < deadline) {
+    if (existsSync(filePath)) {
+      return true;
+    }
+    Atomics.wait(waitView, 0, 0, 25);
+  }
+  return existsSync(filePath);
+}
+
+function waitForChildClose(
+  child: ChildProcess,
+  timeoutMs: number,
+): Promise<{ code: number | null; signal: NodeJS.Signals | null }> {
+  return new Promise((resolve, reject) => {
+    const timer = setTimeout(() => {
+      child.kill("SIGKILL");
+      reject(new Error("timed out waiting for measured wrapper to exit"));
+    }, timeoutMs);
+    child.once("close", (code, signal) => {
+      clearTimeout(timer);
+      resolve({ code, signal });
+    });
+  });
+}
+
 afterEach(() => {
   for (const dir of tempDirs.splice(0)) {
     rmSync(dir, { recursive: true, force: true });
@@ -213,4 +247,88 @@ describe("plugin lifecycle resource sampler", () => {
       }
     }
   });
+
+  it.runIf(process.platform === "linux")(
+    "exits promptly when externally terminated phases stop during grace",
+    async () => {
+      const dir = makeTempDir();
+      const summary = path.join(dir, "summary.tsv");
+      const readyFile = path.join(dir, "ready.pid");
+      const result = spawn(
+        "node",
+        [
+          scriptPath,
+          summary,
+          "external-fast-stop",
+          "--",
+          "node",
+          "--input-type=module",
+          "--eval",
+          [
+            "import { writeFileSync } from 'node:fs';",
+            "writeFileSync(process.env.READY_FILE, String(process.pid));",
+            "process.on('SIGTERM', () => process.exit(0));",
+            "setInterval(() => {}, 1000);",
+          ].join("\n"),
+        ],
+        {
+          cwd: process.cwd(),
+          env: {
+            ...process.env,
+            OPENCLAW_PLUGIN_LIFECYCLE_PHASE_TIMEOUT_MS: "5000",
+            OPENCLAW_PLUGIN_LIFECYCLE_TIMEOUT_KILL_GRACE_MS: "1500",
+            READY_FILE: readyFile,
+          },
+          stdio: "ignore",
+        },
+      );
+
+      expect(waitForPath(readyFile, 1000)).toBe(true);
+      const started = Date.now();
+      result.kill("SIGTERM");
+      const close = await waitForChildClose(result, 5000);
+
+      expect(Date.now() - started).toBeLessThan(1000);
+      expect(close.signal).toBe("SIGTERM");
+    },
+  );
+
+  it.runIf(process.platform === "linux")(
+    "exits promptly when shell descendants drain during termination grace",
+    async () => {
+      const dir = makeTempDir();
+      const summary = path.join(dir, "summary.tsv");
+      const readyFile = path.join(dir, "ready.pid");
+      const result = spawn(
+        "node",
+        [
+          scriptPath,
+          summary,
+          "external-descendant-drain",
+          "--",
+          "bash",
+          "-lc",
+          'trap "exit 0" TERM; bash -c \'trap "sleep 0.15; exit 0" TERM; printf "%s\\n" "$$" >"$READY_FILE"; while :; do sleep 1; done\' & wait',
+        ],
+        {
+          cwd: process.cwd(),
+          env: {
+            ...process.env,
+            OPENCLAW_PLUGIN_LIFECYCLE_PHASE_TIMEOUT_MS: "5000",
+            OPENCLAW_PLUGIN_LIFECYCLE_TIMEOUT_KILL_GRACE_MS: "1500",
+            READY_FILE: readyFile,
+          },
+          stdio: "ignore",
+        },
+      );
+
+      expect(waitForPath(readyFile, 1000)).toBe(true);
+      const started = Date.now();
+      result.kill("SIGTERM");
+      const close = await waitForChildClose(result, 5000);
+
+      expect(Date.now() - started).toBeLessThan(1000);
+      expect(close.signal).toBe("SIGTERM");
+    },
+  );
 });