diff --git a/.agents/skills/blacksmith-testbox/SKILL.md b/.agents/skills/blacksmith-testbox/SKILL.md
index 4d3a1b34228..7df209fd010 100644
--- a/.agents/skills/blacksmith-testbox/SKILL.md
+++ b/.agents/skills/blacksmith-testbox/SKILL.md
@@ -123,17 +123,22 @@ instantly and boots the CI environment in the background while you work:
     blacksmith testbox warmup ci-check-testbox.yml
     # → tbx_01jkz5b3t9...
 
-Save this ID. You need it for every `run` command.
+Save this ID in the current session. You need it for every `run` command.
+Treat `blacksmith testbox list` as diagnostics, not a reusable work queue.
+Listed boxes can be visible at the org/repo level while still being unusable or
+stale for the current local agent lane.
 
 For OpenClaw maintainer Testbox mode, pre-warm at the start of longer or wider
 tasks:
 
     blacksmith testbox warmup ci-check-testbox.yml --ref main --idle-timeout 90
+    pnpm testbox:claim --id <ID>
 
 Use the build-artifact warmup when e2e/package/build proof benefits from seeded
 `dist/`, `dist-runtime/`, and build-all caches:
 
     blacksmith testbox warmup ci-build-artifacts-testbox.yml --ref main --idle-timeout 90
+    pnpm testbox:claim --id <ID>
 
 Warmup dispatches a GitHub Actions workflow that provisions a VM with the
 full CI environment: dependencies installed, services started, secrets
@@ -178,6 +183,26 @@ The `run` command automatically waits for the testbox to become ready if
 it is still booting, so you can call `run` immediately after warmup without
 needing to check status first.
 
+In OpenClaw, prefer the guarded runner wrapper so stale/reused ids fail before
+the Blacksmith CLI spends time syncing or emits a confusing missing-key error:
+
+    pnpm testbox:run --id <ID> -- "OPENCLAW_TESTBOX=1 pnpm check:changed"
+
+The wrapper refuses to run when the local per-Testbox key is missing or when the
+id was not claimed by this OpenClaw checkout with `pnpm testbox:claim --id
+<ID>`. Treat that as the expected remediation, not as a GitHub account or
+normal SSH-key problem. A local key alone is not enough; a ready box may still
+carry stale rsync state from another lane.
+
+If the agent crashes, the remote box relies on Blacksmith's idle timeout. The
+local OpenClaw claim marker is not deleted automatically, so the wrapper treats
+claims older than 12 hours as stale. Override only for intentional long-running
+work with `OPENCLAW_TESTBOX_CLAIM_TTL_MINUTES=<minutes>`.
+
+Before spending a broad gate on a manually assembled command, you can also run:
+
+    pnpm testbox:sanity -- --id <ID>
+
 ## Downloading files from a testbox
 
 Use the `download` command to retrieve files or directories from a running
@@ -286,16 +311,17 @@ checks that need parity or remote state.
 1. Decide whether the repo's local loop is the right default. For OpenClaw,
    `OPENCLAW_TESTBOX=1` makes Testbox the maintainer default.
 2. If Testbox is warranted, warm up early:
-   `blacksmith testbox warmup ci-check-testbox.yml --ref main --idle-timeout 90` → save the ID
+   `blacksmith testbox warmup ci-check-testbox.yml --ref main --idle-timeout 90` → save the ID,
+   then `pnpm testbox:claim --id <ID>`
 3. Write code while the testbox boots in the background.
 4. Run the remote command when needed:
-   `blacksmith testbox run --id <ID> "pnpm check:changed"`
+   `pnpm testbox:run --id <ID> -- "OPENCLAW_TESTBOX=1 pnpm check:changed"`
 5. If tests fail, fix code and re-run against the same warm box.
 6. If you changed dependency manifests (package.json, etc.), prepend
    the install command: `blacksmith testbox run --id <ID> "npm install && npm test"`
 7. If a narrow PR reports a full sync or the box was reused/expired, sanity
    check the remote copy before a slow gate:
-   `blacksmith testbox run --id <ID> "pnpm testbox:sanity"`.
+   `pnpm testbox:run --id <ID> -- "pnpm testbox:sanity"`.
    If it reports missing root files or mass tracked deletions, stop the box and
    warm a fresh one. Use `OPENCLAW_TESTBOX_ALLOW_MASS_DELETIONS=1` only for an
    intentional large deletion PR.
diff --git a/.agents/skills/openclaw-testing/SKILL.md b/.agents/skills/openclaw-testing/SKILL.md
index 9dc12518ccf..1b2c0a720cb 100644
--- a/.agents/skills/openclaw-testing/SKILL.md
+++ b/.agents/skills/openclaw-testing/SKILL.md
@@ -36,6 +36,14 @@ Prove the touched surface first. Do not reflexively run the whole suite.
 - Prefer GitHub Actions for release/Docker proof when the workflow already has the prepared image and secrets.
 - Use `scripts/committer "<msg>" <paths...>` when committing; stage only your files.
 - If deps are missing, run `pnpm install`, retry once, then report the first actionable error.
+- For Blacksmith Testbox proof, reuse only an id warmed and claimed in this
+  operator session. `blacksmith testbox list` is diagnostics only; a listed id
+  can have a local key and still carry stale rsync state from another lane.
+  After warmup, run `pnpm testbox:claim --id <id>`, then prefer
+  `pnpm testbox:run --id <id> -- "<command>"` for OpenClaw gates so stale
+  org-visible ids fail fast before syncing. Claims older than 12 hours are
+  stale unless `OPENCLAW_TESTBOX_CLAIM_TTL_MINUTES` is explicitly set for long
+  work.
 
 ## Local Test Shortcuts
 
diff --git a/package.json b/package.json
index 64a5876780e..47248abb7db 100644
--- a/package.json
+++ b/package.json
@@ -1569,6 +1569,8 @@
     "test:voicecall:closedloop": "node scripts/test-voicecall-closedloop.mjs",
     "test:watch": "node scripts/test-projects.mjs --watch",
     "test:windows:ci": "node scripts/test-projects.mjs src/shared/runtime-import.test.ts src/plugins/import-specifier.test.ts src/process/exec.windows.test.ts src/process/windows-command.test.ts src/infra/windows-install-roots.test.ts extensions/lobster/src/lobster-runner.test.ts test/scripts/npm-runner.test.ts test/scripts/pnpm-runner.test.ts test/scripts/ui.test.ts test/scripts/vitest-process-group.test.ts",
+    "testbox:claim": "node scripts/blacksmith-testbox-runner.mjs --claim",
+    "testbox:run": "node scripts/blacksmith-testbox-runner.mjs",
     "testbox:sanity": "node scripts/testbox-sync-sanity.mjs",
     "tool-display:check": "node --import tsx scripts/tool-display.ts --check",
     "tool-display:write": "node --import tsx scripts/tool-display.ts --write",
diff --git a/scripts/blacksmith-testbox-runner.mjs b/scripts/blacksmith-testbox-runner.mjs
new file mode 100644
index 00000000000..dddd3911e69
--- /dev/null
+++ b/scripts/blacksmith-testbox-runner.mjs
@@ -0,0 +1,122 @@
+#!/usr/bin/env node
+
+import { execFileSync, spawnSync } from "node:child_process";
+import path from "node:path";
+import { pathToFileURL } from "node:url";
+import {
+  evaluateLocalTestboxKey,
+  evaluateOpenClawTestboxClaim,
+  resolveTestboxId,
+  writeOpenClawTestboxClaim,
+} from "./blacksmith-testbox-state.mjs";
+
+function git(args, cwd) {
+  return execFileSync("git", args, { cwd, encoding: "utf8" });
+}
+
+export function splitRunnerArgs(argv = []) {
+  const separatorIndex = argv.indexOf("--");
+  if (separatorIndex === -1) {
+    return { runnerArgs: argv, commandArgs: [] };
+  }
+  return {
+    runnerArgs: argv.slice(0, separatorIndex),
+    commandArgs: argv.slice(separatorIndex + 1),
+  };
+}
+
+export function buildBlacksmithRunArgs({ commandArgs, testboxId }) {
+  const command = commandArgs.join(" ").trim();
+  if (!command) {
+    return [];
+  }
+  return ["testbox", "run", "--id", testboxId, command];
+}
+
+function hasClaimFlag(runnerArgs) {
+  return runnerArgs.includes("--claim") || runnerArgs.includes("--claim-fresh");
+}
+
+function stripRunnerOnlyFlags(runnerArgs) {
+  return runnerArgs.filter((arg) => arg !== "--claim" && arg !== "--claim-fresh");
+}
+
+export function runBlacksmithTestboxRunner({
+  argv = process.argv.slice(2),
+  cwd = process.cwd(),
+  env = process.env,
+  spawn = spawnSync,
+  stderr = process.stderr,
+  stdout = process.stdout,
+} = {}) {
+  const { runnerArgs, commandArgs } = splitRunnerArgs(argv);
+  const shouldClaim = hasClaimFlag(runnerArgs);
+  const testboxId = resolveTestboxId({ argv: stripRunnerOnlyFlags(runnerArgs), env });
+  if (!testboxId) {
+    stderr.write(
+      "Missing Testbox id. Pass `--id <tbx_id>` or set OPENCLAW_TESTBOX_ID from this session's warmup output.\n",
+    );
+    return 2;
+  }
+
+  const keyResult = evaluateLocalTestboxKey({ env, testboxId });
+  if (!keyResult.ok) {
+    stderr.write(`${keyResult.problems.join("\n")}\n`);
+    stderr.write(
+      "Refusing to reuse a remote-visible Testbox without the local private key. Run:\n" +
+        "  blacksmith testbox warmup ci-check-testbox.yml --ref main --idle-timeout 90\n",
+    );
+    return 2;
+  }
+
+  const root = git(["rev-parse", "--show-toplevel"], cwd).trim();
+  if (path.resolve(cwd) !== path.resolve(root)) {
+    stderr.write(
+      `Refusing to run Testbox sync from ${cwd}; run from repo root ${root} so rsync does not mirror a subdirectory.\n`,
+    );
+    return 2;
+  }
+
+  if (shouldClaim) {
+    const claim = writeOpenClawTestboxClaim({ cwd: root, env, testboxId });
+    stdout.write(`OpenClaw Testbox claim written: ${testboxId} -> ${claim.claimPath}\n`);
+  } else {
+    const claimResult = evaluateOpenClawTestboxClaim({
+      cwd: root,
+      env,
+      testboxId,
+    });
+    if (!claimResult.ok) {
+      stderr.write(`${claimResult.problems.join("\n")}\n`);
+      stderr.write(
+        "Refusing to run a Testbox that was not claimed by this OpenClaw checkout. Run:\n" +
+          "  blacksmith testbox warmup ci-check-testbox.yml --ref main --idle-timeout 90\n" +
+          "  pnpm testbox:claim --id <new_tbx_id>\n",
+      );
+      return 2;
+    }
+  }
+
+  const blacksmithArgs = buildBlacksmithRunArgs({ commandArgs, testboxId });
+  if (blacksmithArgs.length === 0) {
+    stdout.write(`Testbox local key and OpenClaw claim ok: ${testboxId}\n`);
+    return 0;
+  }
+
+  const result = spawn("blacksmith", blacksmithArgs, {
+    cwd,
+    env,
+    stdio: "inherit",
+  });
+  if (typeof result.status === "number") {
+    return result.status;
+  }
+  if (result.error) {
+    stderr.write(`Failed to start blacksmith: ${result.error.message}\n`);
+  }
+  return 1;
+}
+
+if (import.meta.url === pathToFileURL(process.argv[1] ?? "").href) {
+  process.exitCode = runBlacksmithTestboxRunner();
+}
diff --git a/scripts/blacksmith-testbox-state.mjs b/scripts/blacksmith-testbox-state.mjs
new file mode 100644
index 00000000000..6f68b96037f
--- /dev/null
+++ b/scripts/blacksmith-testbox-state.mjs
@@ -0,0 +1,194 @@
+import fs from "node:fs";
+import path from "node:path";
+
+const DEFAULT_OPENCLAW_TESTBOX_CLAIM_TTL_MINUTES = 12 * 60;
+const TESTBOX_ID_PATTERN = /^tbx_[a-z0-9]+$/u;
+const OPENCLAW_TESTBOX_CLAIM_FILE = "openclaw-runner.json";
+
+function parsePositiveInteger(value, fallback) {
+  if (!value) {
+    return fallback;
+  }
+  const parsed = Number.parseInt(value, 10);
+  return Number.isFinite(parsed) && parsed > 0 ? parsed : fallback;
+}
+
+export function parseTestboxIdArg(argv = []) {
+  for (let index = 0; index < argv.length; index += 1) {
+    const value = argv[index];
+    if (value === "--id" || value === "--testbox-id") {
+      return argv[index + 1] ?? "";
+    }
+    if (value?.startsWith("--id=")) {
+      return value.slice("--id=".length);
+    }
+    if (value?.startsWith("--testbox-id=")) {
+      return value.slice("--testbox-id=".length);
+    }
+  }
+  return "";
+}
+
+export function resolveTestboxId({ argv = [], env = process.env } = {}) {
+  return (
+    parseTestboxIdArg(argv) ||
+    env.OPENCLAW_TESTBOX_ID ||
+    env.BLACKSMITH_TESTBOX_ID ||
+    env.TESTBOX_ID ||
+    ""
+  ).trim();
+}
+
+export function resolveBlacksmithTestboxStateDir({ env = process.env, homeDir } = {}) {
+  if (env.OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR) {
+    return env.OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR;
+  }
+  const blacksmithHome =
+    env.BLACKSMITH_HOME || path.join(homeDir || env.HOME || process.cwd(), ".blacksmith");
+  return path.join(blacksmithHome, "testboxes");
+}
+
+export function evaluateLocalTestboxKey({
+  testboxId,
+  env = process.env,
+  exists = fs.existsSync,
+  homeDir,
+} = {}) {
+  if (!testboxId) {
+    return { ok: true, checked: false, problems: [] };
+  }
+
+  const problems = [];
+  if (!TESTBOX_ID_PATTERN.test(testboxId)) {
+    problems.push(`invalid Testbox id: ${testboxId}`);
+    return {
+      ok: false,
+      checked: true,
+      keyPath: "",
+      problems,
+      testboxId,
+    };
+  }
+
+  const stateDir = resolveBlacksmithTestboxStateDir({ env, homeDir });
+  const testboxDir = path.join(stateDir, testboxId);
+  const keyPath = path.join(testboxDir, "id_ed25519");
+  if (!exists(keyPath)) {
+    problems.push(
+      `local Testbox SSH key missing for ${testboxId}: expected ${keyPath}. ` +
+        "This id may be visible in `blacksmith testbox list` but unusable by this operator; warm a fresh box instead.",
+    );
+  }
+
+  return {
+    ok: problems.length === 0,
+    checked: true,
+    keyPath,
+    problems,
+    testboxDir,
+    testboxId,
+  };
+}
+
+export function resolveOpenClawTestboxClaimPath({ testboxId, env = process.env, homeDir } = {}) {
+  const stateDir = resolveBlacksmithTestboxStateDir({ env, homeDir });
+  return path.join(stateDir, testboxId, OPENCLAW_TESTBOX_CLAIM_FILE);
+}
+
+export function evaluateOpenClawTestboxClaim({
+  testboxId,
+  cwd,
+  env = process.env,
+  exists = fs.existsSync,
+  now = () => new Date(),
+  readFile = fs.readFileSync,
+  homeDir,
+} = {}) {
+  if (!testboxId) {
+    return { ok: true, checked: false, problems: [] };
+  }
+
+  const claimPath = resolveOpenClawTestboxClaimPath({ testboxId, env, homeDir });
+  const expectedRepoRoot = path.resolve(cwd || process.cwd());
+  const maxAgeMinutes = parsePositiveInteger(
+    env.OPENCLAW_TESTBOX_CLAIM_TTL_MINUTES,
+    DEFAULT_OPENCLAW_TESTBOX_CLAIM_TTL_MINUTES,
+  );
+  const problems = [];
+
+  if (!exists(claimPath)) {
+    problems.push(
+      `OpenClaw Testbox claim missing for ${testboxId}: expected ${claimPath}. ` +
+        "Do not reuse ids from `blacksmith testbox list`; warm a fresh box and claim it with `pnpm testbox:claim --id <id>`.",
+    );
+    return {
+      ok: false,
+      checked: true,
+      claimPath,
+      expectedRepoRoot,
+      problems,
+      testboxId,
+    };
+  }
+
+  let claim;
+  try {
+    claim = JSON.parse(readFile(claimPath, "utf8"));
+  } catch (error) {
+    problems.push(`OpenClaw Testbox claim is unreadable for ${testboxId}: ${error.message}`);
+  }
+
+  const claimedRepoRoot = claim?.repoRoot ? path.resolve(claim.repoRoot) : "";
+  if (!claimedRepoRoot) {
+    problems.push(`OpenClaw Testbox claim is missing repoRoot for ${testboxId}: ${claimPath}`);
+  } else if (claimedRepoRoot !== expectedRepoRoot) {
+    problems.push(
+      `OpenClaw Testbox claim repo mismatch for ${testboxId}: claimed ${claimedRepoRoot}, current ${expectedRepoRoot}. ` +
+        "Warm and claim a fresh box for this checkout.",
+    );
+  }
+
+  const claimedAtMs = Date.parse(claim?.claimedAt ?? "");
+  if (!Number.isFinite(claimedAtMs)) {
+    problems.push(`OpenClaw Testbox claim is missing claimedAt for ${testboxId}: ${claimPath}`);
+  } else {
+    const ageMinutes = Math.floor((now().getTime() - claimedAtMs) / 60000);
+    if (ageMinutes > maxAgeMinutes) {
+      problems.push(
+        `OpenClaw Testbox claim is stale for ${testboxId}: ${ageMinutes}m old, limit ${maxAgeMinutes}m. ` +
+          "Warm and claim a fresh box after crashes or long pauses.",
+      );
+    }
+  }
+
+  return {
+    ok: problems.length === 0,
+    checked: true,
+    claim,
+    claimPath,
+    expectedRepoRoot,
+    problems,
+    testboxId,
+  };
+}
+
+export function writeOpenClawTestboxClaim({
+  testboxId,
+  cwd,
+  env = process.env,
+  homeDir,
+  mkdir = fs.mkdirSync,
+  writeFile = fs.writeFileSync,
+  now = () => new Date(),
+} = {}) {
+  const claimPath = resolveOpenClawTestboxClaimPath({ testboxId, env, homeDir });
+  const repoRoot = path.resolve(cwd || process.cwd());
+  const payload = {
+    claimedAt: now().toISOString(),
+    repoRoot,
+    runnerVersion: 1,
+  };
+  mkdir(path.dirname(claimPath), { recursive: true });
+  writeFile(claimPath, `${JSON.stringify(payload, null, 2)}\n`);
+  return { claimPath, payload, testboxId };
+}
diff --git a/scripts/test-projects.test-support.mjs b/scripts/test-projects.test-support.mjs
index 9094ea7b070..a74674cc3e6 100644
--- a/scripts/test-projects.test-support.mjs
+++ b/scripts/test-projects.test-support.mjs
@@ -267,6 +267,8 @@ const TOOLING_SOURCE_TEST_TARGETS = new Map([
   ["scripts/test-projects.mjs", ["test/scripts/test-projects.test.ts"]],
   ["scripts/test-projects.test-support.d.mts", ["test/scripts/test-projects.test.ts"]],
   ["scripts/test-projects.test-support.mjs", ["test/scripts/test-projects.test.ts"]],
+  ["scripts/blacksmith-testbox-state.mjs", ["test/scripts/blacksmith-testbox-state.test.ts"]],
+  ["scripts/blacksmith-testbox-runner.mjs", ["test/scripts/blacksmith-testbox-runner.test.ts"]],
   ["scripts/testbox-sync-sanity.mjs", ["test/scripts/testbox-sync-sanity.test.ts"]],
 ]);
 const TOOLING_TEST_TARGETS = new Map([
@@ -279,6 +281,14 @@ const TOOLING_TEST_TARGETS = new Map([
     ["test/scripts/plugin-prerelease-test-plan.test.ts"],
   ],
   ["test/scripts/test-projects.test.ts", ["test/scripts/test-projects.test.ts"]],
+  [
+    "test/scripts/blacksmith-testbox-runner.test.ts",
+    ["test/scripts/blacksmith-testbox-runner.test.ts"],
+  ],
+  [
+    "test/scripts/blacksmith-testbox-state.test.ts",
+    ["test/scripts/blacksmith-testbox-state.test.ts"],
+  ],
   ["test/scripts/testbox-sync-sanity.test.ts", ["test/scripts/testbox-sync-sanity.test.ts"]],
   [
     "test/scripts/vitest-local-scheduling.test.ts",
diff --git a/scripts/testbox-sync-sanity.mjs b/scripts/testbox-sync-sanity.mjs
index 6499332d2bf..6942c385f58 100644
--- a/scripts/testbox-sync-sanity.mjs
+++ b/scripts/testbox-sync-sanity.mjs
@@ -4,6 +4,11 @@ import { execFileSync } from "node:child_process";
 import fs from "node:fs";
 import path from "node:path";
 import { pathToFileURL } from "node:url";
+import {
+  evaluateLocalTestboxKey,
+  evaluateOpenClawTestboxClaim,
+  resolveTestboxId,
+} from "./blacksmith-testbox-state.mjs";
 
 const DEFAULT_DELETION_THRESHOLD = 200;
 const REQUIRED_ROOT_FILES = ["package.json", "pnpm-lock.yaml", ".gitignore"];
@@ -78,11 +83,22 @@ function git(args, cwd) {
 export function runTestboxSyncSanity({
   cwd = process.cwd(),
   env = process.env,
+  argv = process.argv.slice(2),
   stdout = process.stdout,
   stderr = process.stderr,
 } = {}) {
   const root = git(["rev-parse", "--show-toplevel"], cwd).trim();
   const statusRaw = git(["status", "--short", "--untracked-files=all"], root);
+  const testboxId = resolveTestboxId({ argv, env });
+  const keyResult = evaluateLocalTestboxKey({
+    env,
+    testboxId,
+  });
+  const claimResult = evaluateOpenClawTestboxClaim({
+    cwd: root,
+    env,
+    testboxId,
+  });
   const result = evaluateTestboxSyncSanity({
     cwd: root,
     statusRaw,
@@ -92,13 +108,21 @@ export function runTestboxSyncSanity({
     ),
     allowMassDeletions: parseBooleanEnv(env.OPENCLAW_TESTBOX_ALLOW_MASS_DELETIONS),
   });
+  result.problems.push(...keyResult.problems);
+  result.problems.push(...claimResult.problems);
+  result.ok = result.problems.length === 0;
 
   if (!result.ok) {
     stderr.write(`Testbox sync sanity failed:\n- ${result.problems.join("\n- ")}\n`);
-    stderr.write("Warm a fresh box or rerun from a clean repo root before spending a gate.\n");
+    stderr.write(
+      "Warm a fresh box, keep using the id from this session, or rerun from a clean repo root before spending a gate.\n",
+    );
     return 1;
   }
 
+  if (keyResult.checked) {
+    stdout.write(`Testbox local key and OpenClaw claim ok: ${keyResult.testboxId}\n`);
+  }
   stdout.write(
     `Testbox sync sanity ok: ${result.statusEntryCount} changed entries, ${result.trackedDeletionCount} tracked deletions.\n`,
   );
diff --git a/test/scripts/blacksmith-testbox-runner.test.ts b/test/scripts/blacksmith-testbox-runner.test.ts
new file mode 100644
index 00000000000..b61727f96c0
--- /dev/null
+++ b/test/scripts/blacksmith-testbox-runner.test.ts
@@ -0,0 +1,94 @@
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
+import { describe, expect, it } from "vitest";
+import {
+  buildBlacksmithRunArgs,
+  runBlacksmithTestboxRunner,
+  splitRunnerArgs,
+} from "../../scripts/blacksmith-testbox-runner.mjs";
+
+describe("blacksmith testbox runner", () => {
+  it("splits runner args from the remote command", () => {
+    expect(
+      splitRunnerArgs(["--id", "tbx_abc123", "--", "OPENCLAW_TESTBOX=1", "pnpm", "check:changed"]),
+    ).toEqual({
+      runnerArgs: ["--id", "tbx_abc123"],
+      commandArgs: ["OPENCLAW_TESTBOX=1", "pnpm", "check:changed"],
+    });
+  });
+
+  it("builds blacksmith run arguments", () => {
+    expect(
+      buildBlacksmithRunArgs({
+        commandArgs: ["OPENCLAW_TESTBOX=1", "pnpm", "check:changed"],
+        testboxId: "tbx_abc123",
+      }),
+    ).toEqual(["testbox", "run", "--id", "tbx_abc123", "OPENCLAW_TESTBOX=1 pnpm check:changed"]);
+  });
+
+  it("refuses to run a remote-visible id without a local private key", () => {
+    let spawned = false;
+    const stderr = { write: (value: string) => value.length };
+    const code = runBlacksmithTestboxRunner({
+      argv: ["--id", "tbx_01kqap50t9fqggzw1akg5dtmmq", "--", "pnpm", "check:changed"],
+      env: { OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR: "/state/testboxes" },
+      spawn: () => {
+        spawned = true;
+        return { status: 0 };
+      },
+      stderr,
+    });
+
+    expect(code).toBe(2);
+    expect(spawned).toBe(false);
+  });
+
+  it("refuses to run a keyed id that was not claimed by this checkout", () => {
+    const stateDir = fs.mkdtempSync(path.join(os.tmpdir(), "openclaw-testbox-runner-"));
+    const testboxDir = path.join(stateDir, "tbx_01kqap50t9fqggzw1akg5dtmmq");
+    fs.mkdirSync(testboxDir, { recursive: true });
+    fs.writeFileSync(path.join(testboxDir, "id_ed25519"), "test-key\n");
+
+    let spawned = false;
+    let stderrText = "";
+    const code = runBlacksmithTestboxRunner({
+      argv: ["--id", "tbx_01kqap50t9fqggzw1akg5dtmmq", "--", "pnpm", "check:changed"],
+      env: { ...process.env, OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR: stateDir },
+      spawn: () => {
+        spawned = true;
+        return { status: 0 };
+      },
+      stderr: { write: (value: string) => (stderrText += value) },
+    });
+
+    expect(code).toBe(2);
+    expect(spawned).toBe(false);
+    expect(stderrText).toContain("OpenClaw Testbox claim missing");
+  });
+
+  it("claims a keyed id without spawning when no remote command is supplied", () => {
+    const stateDir = fs.mkdtempSync(path.join(os.tmpdir(), "openclaw-testbox-runner-"));
+    const testboxDir = path.join(stateDir, "tbx_01kqap50t9fqggzw1akg5dtmmq");
+    const claimPath = path.join(testboxDir, "openclaw-runner.json");
+    fs.mkdirSync(testboxDir, { recursive: true });
+    fs.writeFileSync(path.join(testboxDir, "id_ed25519"), "test-key\n");
+
+    let spawned = false;
+    let stdoutText = "";
+    const code = runBlacksmithTestboxRunner({
+      argv: ["--claim", "--id", "tbx_01kqap50t9fqggzw1akg5dtmmq"],
+      env: { ...process.env, OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR: stateDir },
+      spawn: () => {
+        spawned = true;
+        return { status: 0 };
+      },
+      stdout: { write: (value: string) => (stdoutText += value) },
+    });
+
+    expect(code).toBe(0);
+    expect(spawned).toBe(false);
+    expect(stdoutText).toContain("OpenClaw Testbox claim written");
+    expect(JSON.parse(fs.readFileSync(claimPath, "utf8")).repoRoot).toBe(process.cwd());
+  });
+});
diff --git a/test/scripts/blacksmith-testbox-state.test.ts b/test/scripts/blacksmith-testbox-state.test.ts
new file mode 100644
index 00000000000..f536ab749e5
--- /dev/null
+++ b/test/scripts/blacksmith-testbox-state.test.ts
@@ -0,0 +1,119 @@
+import { describe, expect, it } from "vitest";
+import {
+  evaluateLocalTestboxKey,
+  evaluateOpenClawTestboxClaim,
+  parseTestboxIdArg,
+  resolveTestboxId,
+  writeOpenClawTestboxClaim,
+} from "../../scripts/blacksmith-testbox-state.mjs";
+
+describe("blacksmith testbox state", () => {
+  it("parses Testbox ids from args and env", () => {
+    expect(parseTestboxIdArg(["--id", "tbx_abc123"])).toBe("tbx_abc123");
+    expect(parseTestboxIdArg(["--testbox-id=tbx_def456"])).toBe("tbx_def456");
+    expect(resolveTestboxId({ argv: [], env: { OPENCLAW_TESTBOX_ID: "tbx_env123" } })).toBe(
+      "tbx_env123",
+    );
+  });
+
+  it("fails when a remote-visible Testbox id has no local private key", () => {
+    const result = evaluateLocalTestboxKey({
+      env: { OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR: "/state/testboxes" },
+      exists: () => false,
+      testboxId: "tbx_01kqap50t9fqggzw1akg5dtmmq",
+    });
+
+    expect(result.ok).toBe(false);
+    expect(result.keyPath).toBe("/state/testboxes/tbx_01kqap50t9fqggzw1akg5dtmmq/id_ed25519");
+    expect(result.problems[0]).toContain("local Testbox SSH key missing");
+  });
+
+  it("accepts a Testbox id with a local private key", () => {
+    const result = evaluateLocalTestboxKey({
+      env: { OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR: "/state/testboxes" },
+      exists: (file) => file.endsWith("/tbx_01kqap50t9fqggzw1akg5dtmmq/id_ed25519"),
+      testboxId: "tbx_01kqap50t9fqggzw1akg5dtmmq",
+    });
+
+    expect(result.ok).toBe(true);
+    expect(result.checked).toBe(true);
+  });
+
+  it("fails when a keyed Testbox id has no OpenClaw claim", () => {
+    const result = evaluateOpenClawTestboxClaim({
+      cwd: "/repo",
+      env: { OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR: "/state/testboxes" },
+      exists: () => false,
+      testboxId: "tbx_01kqap50t9fqggzw1akg5dtmmq",
+    });
+
+    expect(result.ok).toBe(false);
+    expect(result.claimPath).toBe(
+      "/state/testboxes/tbx_01kqap50t9fqggzw1akg5dtmmq/openclaw-runner.json",
+    );
+    expect(result.problems[0]).toContain("OpenClaw Testbox claim missing");
+  });
+
+  it("fails when an OpenClaw claim belongs to a different checkout", () => {
+    const result = evaluateOpenClawTestboxClaim({
+      cwd: "/repo/current",
+      env: { OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR: "/state/testboxes" },
+      exists: () => true,
+      now: () => new Date("2026-04-29T12:00:00.000Z"),
+      readFile: () => JSON.stringify({ repoRoot: "/repo/other" }),
+      testboxId: "tbx_01kqap50t9fqggzw1akg5dtmmq",
+    });
+
+    expect(result.ok).toBe(false);
+    expect(result.problems[0]).toContain("claim repo mismatch");
+  });
+
+  it("fails when an OpenClaw claim is stale after a crash or long pause", () => {
+    const result = evaluateOpenClawTestboxClaim({
+      cwd: "/repo/current",
+      env: {
+        OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR: "/state/testboxes",
+        OPENCLAW_TESTBOX_CLAIM_TTL_MINUTES: "90",
+      },
+      exists: () => true,
+      now: () => new Date("2026-04-29T14:00:00.000Z"),
+      readFile: () =>
+        JSON.stringify({
+          claimedAt: "2026-04-29T12:00:00.000Z",
+          repoRoot: "/repo/current",
+        }),
+      testboxId: "tbx_01kqap50t9fqggzw1akg5dtmmq",
+    });
+
+    expect(result.ok).toBe(false);
+    expect(result.problems[0]).toContain("claim is stale");
+  });
+
+  it("writes and accepts an OpenClaw Testbox claim for the current checkout", () => {
+    const writes = new Map<string, string>();
+    const claim = writeOpenClawTestboxClaim({
+      cwd: "/repo/current",
+      env: { OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR: "/state/testboxes" },
+      mkdir: () => undefined,
+      now: () => new Date("2026-04-29T12:00:00.000Z"),
+      testboxId: "tbx_01kqap50t9fqggzw1akg5dtmmq",
+      writeFile: (file, value) => writes.set(file, value),
+    });
+
+    expect(claim.payload).toEqual({
+      claimedAt: "2026-04-29T12:00:00.000Z",
+      repoRoot: "/repo/current",
+      runnerVersion: 1,
+    });
+    expect(
+      evaluateOpenClawTestboxClaim({
+        cwd: "/repo/current",
+        env: { OPENCLAW_BLACKSMITH_TESTBOX_STATE_DIR: "/state/testboxes" },
+        exists: (file) => writes.has(file),
+        now: () => new Date("2026-04-29T12:30:00.000Z"),
+        readFile: (file) => writes.get(file) ?? "",
+        testboxId: "tbx_01kqap50t9fqggzw1akg5dtmmq",
+      }).ok,
+    ).toBe(true);
+  });
+});