diff --git a/cli/__tests__/adapters.claude.environment.test.mjs b/cli/__tests__/adapters.claude.environment.test.mjs
index 322cc8112f..0a088b65fb 100644
--- a/cli/__tests__/adapters.claude.environment.test.mjs
+++ b/cli/__tests__/adapters.claude.environment.test.mjs
@@ -1386,11 +1386,12 @@ describe('claude adapter — a workspace seat', () => {
     }
   });
 
-  test('under bwrap it refuses to spawn', async () => {
+  test('under bwrap on a Mac it refuses before preparing any state', async () => {
     const { impl, calls } = makeSpawnImpl();
     await expect(workspaceSpawn(impl, { mode: 'bwrap', trust: 'workspace' }))
-      .rejects.toThrow(/workspace Claude agents run on macOS only for now/);
+      .rejects.toThrow(/workspace Claude agents require bwrap: bwrap is Linux-only/);
     expect(calls).toHaveLength(0);
+    expect(fs.readdirSync(publicState)).toEqual([]);
   });
 
   test('with an unenforced mode it refuses rather than falls through to a bare spawn', async () => {
@@ -1401,6 +1402,215 @@ describe('claude adapter — a workspace seat', () => {
   });
 });
 
+// A workspace seat on Linux runs under bwrap. bwrap used to make the project
+// its HOME, so its transcripts landed in the person's project and it had no
+// login, and the adapter refused the combination. The seat now gets the same
+// per-seat state folder macOS uses, outside the project, with a copy of the
+// person's Claude login in it.
+describe('claude adapter — a workspace seat on Linux', () => {
+  const originalPlatform = process.platform;
+  let cwd;
+  let state;
+  let operatorClaude;
+  const login = '{"claudeAiOauth":{"accessToken":"test-only"}}\n';
+
+  beforeEach(() => {
+    cwd = fs.mkdtempSync(path.join(os.tmpdir(), 'cli-claude-linux-ws-'));
+    state = fs.mkdtempSync(path.join(os.tmpdir(), 'cli-claude-linux-state-'));
+    operatorClaude = fs.mkdtempSync(path.join(os.tmpdir(), 'cli-claude-linux-login-'));
+    fs.writeFileSync(path.join(operatorClaude, '.credentials.json'), login, { mode: 0o600 });
+    Object.defineProperty(process, 'platform', { value: 'linux' });
+  });
+  afterEach(() => {
+    Object.defineProperty(process, 'platform', { value: originalPlatform });
+    for (const dir of [cwd, state, operatorClaude]) fs.rmSync(dir, { recursive: true, force: true });
+  });
+
+  // Plays the child: it looks for its login under the HOME it was given and
+  // writes its transcript there, as claude does.
+  const childImpl = () => {
+    const calls = [];
+    const impl = (cmd, args, opts) => {
+      // bwrap sets the child's HOME with --setenv; that is the one it sees.
+      const home = args[args.indexOf('HOME') + 1];
+      const loginPath = path.join(home, '.claude', '.credentials.json');
+      const foundLogin = fs.existsSync(loginPath) ? fs.readFileSync(loginPath, 'utf8') : null;
+      const sid = args[args.indexOf('--session-id') + 1];
+      const dir = path.join(home, '.claude', 'projects', cwd.replace(/[^a-zA-Z0-9]/g, '-'));
+      fs.mkdirSync(dir, { recursive: true });
+      fs.writeFileSync(path.join(dir, `${sid}.jsonl`), `${JSON.stringify({
+        type: 'assistant',
+        message: { usage: { input_tokens: 1, cache_creation_input_tokens: 2, cache_read_input_tokens: 40 } },
+      })}\n`);
+      calls.push({ cmd, args, opts, foundLogin });
+      return fakeChild({ stdout: 'ok' });
+    };
+    return { impl, calls };
+  };
+
+  const linuxSpawn = (impl, sandbox = { trust: 'workspace' }, env = {}) => claude.spawn('hi', {
+    agentName: 'linux-workspace-test',
+    sessionId: null,
+    cwd,
+    env: { PATH: process.env.PATH, CLAUDE_CONFIG_DIR: operatorClaude, ...env },
+    environment: { model: 'test-model', sandbox },
+    memoryLongTerm: '',
+    _publicClaudeState: state,
+    _detectBwrap: () => ({ available: true, path: 'bwrap' }),
+    _spawnImpl: impl,
+  });
+
+  const flagTriples = (args, flag) => args.flatMap((arg, i) => (
+    arg === flag ? [[args[i + 1], args[i + 2]]] : []
+  ));
+
+  test('runs in bwrap with a HOME outside the project, finds its login, and writes nothing into the project', async () => {
+    const { impl, calls } = childImpl();
+    const res = await linuxSpawn(impl);
+
+    expect(calls).toHaveLength(1);
+    const { cmd, args, opts, foundLogin } = calls[0];
+    expect(cmd).toBe('bwrap');
+    const outer = args.slice(0, args.indexOf('--'));
+    expect(outer.slice(outer.indexOf('HOME') - 1, outer.indexOf('HOME') + 2))
+      .toEqual(['--setenv', 'HOME', state]);
+    expect(opts.env.HOME).toBe(state);
+    expect(opts.env.CLAUDE_CONFIG_DIR).toBeUndefined();
+    // The state folder is the only writable bind; with no write grant the
+    // project is read-only.
+    expect(flagTriples(outer, '--bind')).toEqual([[state, state]]);
+    expect(flagTriples(outer, '--ro-bind')).toContainEqual([cwd, cwd]);
+
+    expect(foundLogin).toBe(login);
+    const copy = path.join(state, '.claude', '.credentials.json');
+    expect(fs.lstatSync(copy).isFile()).toBe(true);
+    expect(fs.statSync(copy).mode & 0o777).toBe(0o600);
+    expect(fs.statSync(path.join(state, '.claude')).mode & 0o777).toBe(0o700);
+    expect(fs.readdirSync(cwd)).toEqual([]);
+    // TASK-440 reads the transcript from the HOME the child wrote under.
+    expect(res.contextTokens).toBe(43);
+
+    // The seat runs the workspace tier's policy, not the public seat's.
+    const inner = args.slice(args.indexOf('--') + 1);
+    expect(inner).toEqual(expect.arrayContaining(['--permission-mode', 'dontAsk']));
+    expect(inner.join(' ')).toContain('Read(./.env)');
+  });
+
+  test('a write grant makes the project writable and keeps its .git read-only', async () => {
+    const gitDir = path.join(cwd, '.git');
+    fs.mkdirSync(gitDir);
+    const { impl, calls } = childImpl();
+    await linuxSpawn(impl, { trust: 'workspace', allow: ['write'] });
+
+    const outer = calls[0].args.slice(0, calls[0].args.indexOf('--'));
+    expect(flagTriples(outer, '--bind')).toEqual([[state, state], [cwd, cwd]]);
+    // Strict, not -try: a .git that vanished must stop bwrap, not go unbound.
+    expect(flagTriples(outer, '--ro-bind')).toContainEqual([gitDir, gitDir]);
+    // .git is bound after the project, so it lands on top of it.
+    const bindAt = (flag, p) => outer.findIndex((arg, i) => arg === flag && outer[i + 1] === p);
+    expect(bindAt('--ro-bind', gitDir)).toBeGreaterThan(bindAt('--bind', cwd));
+  });
+
+  test('a write grant on a project with no .git refuses, and creates nothing in it', async () => {
+    const { impl, calls } = childImpl();
+    await expect(linuxSpawn(impl, { trust: 'workspace', allow: ['write'] }))
+      .rejects.toThrow(/need the project to be a git repository/);
+    expect(calls).toHaveLength(0);
+    expect(fs.readdirSync(cwd)).toEqual([]);
+  });
+
+  test('a write grant refuses a .git that is a symlink', async () => {
+    const elsewhere = fs.mkdtempSync(path.join(os.tmpdir(), 'cli-claude-linux-git-'));
+    try {
+      fs.symlinkSync(elsewhere, path.join(cwd, '.git'));
+      const { impl, calls } = childImpl();
+      await expect(linuxSpawn(impl, { trust: 'workspace', allow: ['write'] }))
+        .rejects.toThrow(/need the project to be a git repository/);
+      expect(calls).toHaveLength(0);
+    } finally {
+      fs.rmSync(elsewhere, { recursive: true, force: true });
+    }
+  });
+
+  test('without a write grant a project with no .git still runs, read-only', async () => {
+    const { impl, calls } = childImpl();
+    await linuxSpawn(impl);
+    const outer = calls[0].args.slice(0, calls[0].args.indexOf('--'));
+    expect(flagTriples(outer, '--ro-bind')).toContainEqual([cwd, cwd]);
+    expect(fs.readdirSync(cwd)).toEqual([]);
+  });
+
+  test('refuses a login that is a symlink, and spawns nothing', async () => {
+    const real = path.join(operatorClaude, 'elsewhere.json');
+    fs.renameSync(path.join(operatorClaude, '.credentials.json'), real);
+    fs.symlinkSync(real, path.join(operatorClaude, '.credentials.json'));
+    const { impl, calls } = childImpl();
+
+    await expect(linuxSpawn(impl)).rejects.toThrow(/refusing a Claude login that is not a regular file/);
+    expect(calls).toHaveLength(0);
+    expect(fs.existsSync(path.join(state, '.claude', '.credentials.json'))).toBe(false);
+  });
+
+  test('refuses a login that is not a regular file, checked on the opened file', async () => {
+    const login = path.join(operatorClaude, '.credentials.json');
+    fs.rmSync(login);
+    fs.mkdirSync(login);
+    const { impl, calls } = childImpl();
+    await expect(linuxSpawn(impl)).rejects.toThrow(/refusing a Claude login that is not a regular file/);
+    expect(calls).toHaveLength(0);
+  });
+
+  test('replaces a symlink the jail left at the copy, rather than writing through it', async () => {
+    const victim = path.join(operatorClaude, 'victim.txt');
+    fs.writeFileSync(victim, 'untouched');
+    fs.mkdirSync(path.join(state, '.claude'), { mode: 0o700 });
+    fs.symlinkSync(victim, path.join(state, '.claude', '.credentials.json'));
+    const { impl, calls } = childImpl();
+
+    await linuxSpawn(impl);
+    expect(calls[0].foundLogin).toBe(login);
+    expect(fs.lstatSync(path.join(state, '.claude', '.credentials.json')).isSymbolicLink()).toBe(false);
+    expect(fs.readFileSync(victim, 'utf8')).toBe('untouched');
+  });
+
+  test('a person who logged out is not still signed in here', async () => {
+    fs.rmSync(path.join(operatorClaude, '.credentials.json'));
+    fs.mkdirSync(path.join(state, '.claude'), { mode: 0o700 });
+    fs.writeFileSync(path.join(state, '.claude', '.credentials.json'), login, { mode: 0o600 });
+    const { impl, calls } = childImpl();
+
+    await linuxSpawn(impl);
+    expect(calls[0].foundLogin).toBeNull();
+  });
+
+  test('a host with no usable bwrap refuses before preparing any state', async () => {
+    const { impl, calls } = childImpl();
+    await expect(claude.spawn('hi', {
+      agentName: 'linux-workspace-test',
+      sessionId: null,
+      cwd,
+      env: { PATH: process.env.PATH, CLAUDE_CONFIG_DIR: operatorClaude },
+      environment: { model: 'test-model', sandbox: { trust: 'workspace' } },
+      _publicClaudeState: state,
+      _detectBwrap: () => ({ available: false, error: 'bwrap not found on PATH.' }),
+      _spawnImpl: impl,
+    })).rejects.toThrow(/workspace Claude agents require bwrap: bwrap not found/);
+    expect(calls).toHaveLength(0);
+    expect(fs.readdirSync(state)).toEqual([]);
+  });
+
+  test('a public Linux seat keeps its old jail: the project is its HOME and nothing else is writable', async () => {
+    const { impl, calls } = childImpl();
+    await linuxSpawn(impl, { trust: 'public' });
+
+    const outer = calls[0].args.slice(0, calls[0].args.indexOf('--'));
+    expect(outer.slice(outer.indexOf('HOME') - 1, outer.indexOf('HOME') + 2))
+      .toEqual(['--setenv', 'HOME', cwd]);
+    expect(flagTriples(outer, '--bind')).toEqual([[cwd, cwd]]);
+    expect(fs.readdirSync(state)).toEqual([]);
+  });
+});
+
 describe('claude adapter — a workspace seat\'s git tool', () => {
   let cwd;
   let publicState;
diff --git a/cli/__tests__/bwrap.test.mjs b/cli/__tests__/bwrap.test.mjs
index 52f28dd9f9..cb48d7d017 100644
--- a/cli/__tests__/bwrap.test.mjs
+++ b/cli/__tests__/bwrap.test.mjs
@@ -181,6 +181,43 @@ describe('wrapArgvWithBwrap', () => {
     expect(argv).not.toContain('/home/operator/.config/commonly');
   });
 
+  itLinux('binds an adapter-owned HOME writable, separate from a read-only workspace', () => {
+    const argv = wrapArgvWithBwrap(['claude'], {}, {
+      workspacePath: '/tmp/ws',
+      workspaceReadOnly: true,
+      homePath: '/home/u/.commonly/claude-homes/abc',
+      writablePaths: ['/home/u/.commonly/claude-homes/abc'],
+      readOnlyWorkspaceEntries: ['.git'],
+    });
+    const at = (flag, p) => argv.findIndex((arg, i) => arg === flag && argv[i + 1] === p && argv[i + 2] === p);
+    expect(at('--bind', '/home/u/.commonly/claude-homes/abc')).toBeGreaterThan(-1);
+    expect(at('--ro-bind', '/tmp/ws')).toBeGreaterThan(-1);
+    expect(at('--bind', '/tmp/ws')).toBe(-1);
+    expect(at('--ro-bind-try', '/tmp/ws/.git')).toBeGreaterThan(at('--ro-bind', '/tmp/ws'));
+    const homeIndex = argv.indexOf('HOME');
+    expect(argv[homeIndex + 1]).toBe('/home/u/.commonly/claude-homes/abc');
+  });
+
+  itLinux('in a writable workspace a read-only entry is bound strictly, so a missing one stops bwrap', () => {
+    const argv = wrapArgvWithBwrap(['claude'], {}, {
+      workspacePath: '/tmp/ws', readOnlyWorkspaceEntries: ['.git'],
+    });
+    const at = (flag, p) => argv.findIndex((arg, i) => arg === flag && argv[i + 1] === p && argv[i + 2] === p);
+    expect(at('--ro-bind', '/tmp/ws/.git')).toBeGreaterThan(at('--bind', '/tmp/ws'));
+    expect(at('--ro-bind-try', '/tmp/ws/.git')).toBe(-1);
+  });
+
+  itLinux('rejects a relative writable path and a workspace entry that leaves the workspace', () => {
+    expect(() => wrapArgvWithBwrap(['claude'], {}, {
+      workspacePath: '/tmp/ws', writablePaths: ['state'],
+    })).toThrow(/writablePaths entries must be absolute/);
+    for (const entry of ['../outside', '/etc', 'a/../../b']) {
+      expect(() => wrapArgvWithBwrap(['claude'], {}, {
+        workspacePath: '/tmp/ws', readOnlyWorkspaceEntries: [entry],
+      })).toThrow(/relative names inside the workspace/);
+    }
+  });
+
   itLinux('rejects relative adapter-owned transient paths', () => {
     expect(() => wrapArgvWithBwrap(
       ['claude'],
diff --git a/cli/src/lib/adapters/claude.js b/cli/src/lib/adapters/claude.js
index 2c7ef54c39..3eff813427 100644
--- a/cli/src/lib/adapters/claude.js
+++ b/cli/src/lib/adapters/claude.js
@@ -55,8 +55,10 @@ import {
   lstat,
   mkdir,
   mkdtemp,
+  open,
   readFile,
   readlink,
+  rename,
   rm,
   symlink,
   unlink,
@@ -208,6 +210,29 @@ const statOrNull = async (path) => {
   }
 };
 
+// The non-secret account metadata Claude needs from ~/.claude.json to find its
+// login, and nothing else from that file.
+const claudeAuthMetadata = async () => {
+  const operatorConfigPath = join(homedir(), '.claude.json');
+  const sourceStat = await statOrNull(operatorConfigPath);
+  let source = {};
+  if (sourceStat) {
+    if (!sourceStat.isFile() || sourceStat.isSymbolicLink()) {
+      throw new Error(`refusing non-regular operator Claude config: ${operatorConfigPath}`);
+    }
+    try {
+      source = JSON.parse(await readFile(operatorConfigPath, 'utf8'));
+    } catch (err) {
+      throw new Error(`failed to read operator Claude auth metadata: ${err.message}`);
+    }
+  }
+  const sanitized = { hasCompletedOnboarding: true };
+  for (const key of ['installMethod', 'userID', 'machineID', 'oauthAccount']) {
+    if (source[key] !== undefined) sanitized[key] = source[key];
+  }
+  return sanitized;
+};
+
 // Claude's macOS OAuth credential lives in Keychain, but Claude also needs a
 // small amount of non-secret account metadata from ~/.claude.json to locate
 // it. Never bind or copy the operator's full file: it contains project paths,
@@ -248,35 +273,102 @@ const preparePublicClaudeState = async (ctx) => {
     await symlink(operatorKeychains, stateKeychains);
   }
 
-  const operatorConfigPath = join(homedir(), '.claude.json');
-  const sourceStat = await statOrNull(operatorConfigPath);
-  let source = {};
-  if (sourceStat) {
-    if (!sourceStat.isFile() || sourceStat.isSymbolicLink()) {
-      throw new Error(`refusing non-regular operator Claude config: ${operatorConfigPath}`);
-    }
-    try {
-      source = JSON.parse(await readFile(operatorConfigPath, 'utf8'));
-    } catch (err) {
-      throw new Error(`failed to read operator Claude auth metadata: ${err.message}`);
-    }
-  }
-
-  const sanitized = {
-    hasCompletedOnboarding: true,
-  };
-  for (const key of ['installMethod', 'userID', 'machineID', 'oauthAccount']) {
-    if (source[key] !== undefined) sanitized[key] = source[key];
-  }
   await writeFile(
     configPath,
-    `${JSON.stringify(sanitized, null, 2)}\n`,
+    `${JSON.stringify(await claudeAuthMetadata(), null, 2)}\n`,
     { encoding: 'utf8', mode: 0o600 },
   );
   await chmod(configPath, 0o600);
   return { statePath, tmpPath, configPath };
 };
 
+// Writes a 0600 file into a directory the confined child can also write. The
+// directory must still be a real directory, and the file is written beside the
+// target and renamed over it, so a symlink the child left at either name is
+// replaced, never followed into another of the person's files.
+const replacePrivateFile = async (dir, name, content) => {
+  const dirStat = await statOrNull(dir);
+  if (!dirStat || dirStat.isSymbolicLink() || !dirStat.isDirectory()) {
+    throw new Error(`refusing to write Claude state into a non-directory: ${dir}`);
+  }
+  const target = join(dir, name);
+  const staged = join(dir, `.${name}.${randomUUID()}.tmp`);
+  await writeFile(staged, content, { encoding: 'utf8', mode: 0o600, flag: 'wx' });
+  try {
+    await chmod(staged, 0o600);
+    await rename(staged, target);
+  } catch (err) {
+    await rm(staged, { force: true });
+    throw err;
+  }
+  return target;
+};
+
+// A workspace seat on Linux runs under bwrap, which has no keychain. Claude
+// Code on Linux keeps its login in <config dir>/.credentials.json, so the
+// seat's own state dir gets a copy of the person's, taken fresh each spawn:
+// their own credential on their own machine, the exposure the macOS keychain
+// arm already has. Only the copy is inside the jail. Nothing is written back:
+// the jail can write its copy, and a write-back would let it replace the
+// person's login with one of its choosing. A missing login removes the copy,
+// so a person who logged out is not still signed in here.
+const claudeLoginSource = (env) => join(
+  env?.CLAUDE_CONFIG_DIR || process.env.CLAUDE_CONFIG_DIR || join(homedir(), '.claude'),
+  '.credentials.json',
+);
+
+// Opened once, without following a symlink, and checked on the open handle,
+// so the file read is the file checked (a FIFO cannot hold the open either).
+const carryClaudeLogin = async (env, configDir) => {
+  const source = claudeLoginSource(env);
+  const refuse = () => new Error(`refusing a Claude login that is not a regular file: ${source}`);
+  let handle;
+  try {
+    handle = await open(source, constants.O_RDONLY | constants.O_NOFOLLOW | constants.O_NONBLOCK);
+  } catch (err) {
+    if (err?.code === 'ENOENT') {
+      await rm(join(configDir, '.credentials.json'), { force: true });
+      return null;
+    }
+    if (err?.code === 'ELOOP') throw refuse();
+    throw err;
+  }
+  try {
+    if (!(await handle.stat()).isFile()) throw refuse();
+    return replacePrivateFile(configDir, '.credentials.json', await handle.readFile('utf8'));
+  } finally {
+    await handle.close();
+  }
+};
+
+// State for a workspace seat under bwrap: the same per-seat folder the macOS
+// path uses, outside the person's project, with the auth metadata whitelist
+// and the login copy. The jail binds this folder writable and makes it HOME,
+// so transcripts land here rather than in the project.
+const prepareWorkspaceBwrapClaudeState = async (ctx) => {
+  const identity = ctx.agentName || ctx.cwd || 'anonymous';
+  const identityHash = createHash('sha256').update(identity).digest('hex').slice(0, 20);
+  const statePath = ctx._publicClaudeState || publicClaudeStateRoot(identityHash);
+  const tmpPath = join(statePath, 'tmp');
+  const configDir = join(statePath, '.claude');
+  await mkdir(statePath, { recursive: true, mode: 0o700 });
+  await chmod(statePath, 0o700);
+  for (const dir of [tmpPath, configDir]) {
+    const existing = await statOrNull(dir);
+    if (existing && (existing.isSymbolicLink() || !existing.isDirectory())) {
+      throw new Error(`refusing Claude state path that is not a directory: ${dir}`);
+    }
+    if (!existing) await mkdir(dir, { mode: 0o700 });
+    await chmod(dir, 0o700);
+  }
+
+  const configPath = await replacePrivateFile(
+    statePath, '.claude.json', `${JSON.stringify(await claudeAuthMetadata(), null, 2)}\n`,
+  );
+  const loginPath = await carryClaudeLogin(ctx.env, configDir);
+  return { statePath, tmpPath, configPath, loginPath };
+};
+
 const buildClaudeEnv = (input, state, expansionEnv = {}, credentialFile = null, publicSeat = false) => {
   const source = input || process.env;
   const output = state || publicSeat ? {} : { ...source };
@@ -732,6 +824,9 @@ const prepareArgv = async (innerArgv, ctx) => {
   // get the jail only — a derived Linux seat kept Bash/Write/WebFetch and ran on
   // the operator's own Claude settings inside the namespace (Vera 69578).
   const publicBwrapSandbox = sandboxTrust === 'public' && sandboxMode === 'bwrap';
+  // A workspace seat on Linux: the same jail, with the workspace tier's policy
+  // and a HOME of its own outside the project.
+  const workspaceBwrapSandbox = sandboxTrust === 'workspace' && sandboxMode === 'bwrap';
   const commitHooksPath = ctx.commitAttributionEnv?.COMMONLY_AGENT_HOOKS_PATH || null;
   const originalHooksPath = ctx.commitAttributionEnv?.COMMONLY_AGENT_ORIGINAL_HOOKS_PATH || null;
   const commitHookExecutables = commitHooksPath
@@ -754,12 +849,6 @@ const prepareArgv = async (innerArgv, ctx) => {
   // non-string) used to fall through to the bare `claude` spawn below — an
   // unconfined seat with a public record, which is how a record can claim
   // confinement it never applies (Vera 69548).
-  // bwrap points the child's HOME at its folder (childHome below), so a
-  // workspace seat's transcripts would be written into the person's project.
-  if (sandboxTrust === 'workspace' && sandboxMode === 'bwrap') {
-    throw new Error('workspace Claude agents run on macOS only for now: under bwrap '
-      + 'their transcripts would be written into the project folder');
-  }
   if (isConfinedTrust(sandboxTrust) && !publicNativeSandbox && sandboxMode !== 'bwrap') {
     throw new Error(
       `${sandboxTrust} Claude agents require an enforced sandbox mode `
@@ -818,23 +907,71 @@ const prepareArgv = async (innerArgv, ctx) => {
     };
   }
 
-  if (publicBwrapSandbox) {
+  if (publicBwrapSandbox || workspaceBwrapSandbox) {
     // The mode is chosen here, so the mechanism is verified here: a missing
     // bwrap must fail the seat's derivation with an actionable message, not
     // every one of its spawns with a bare ENOENT (Wren 69586). On a non-Linux
     // host this reports the macOS-only message, same as the wrapper would.
     const bwrap = (ctx._detectBwrap || detectBwrap)();
     if (!bwrap.available) {
-      throw new Error(`public Claude agents require bwrap: ${bwrap.error}`);
+      throw new Error(`${sandboxTrust} Claude agents require bwrap: ${bwrap.error}`);
+    }
+    if (workspaceBwrapSandbox && !ctx.publicClaudeState) {
+      throw new Error('workspace Claude state was not prepared before argv construction');
     }
     innerArgv = [
       ...innerArgv,
-      ...buildPublicClaudePolicyArgs(allowedPatterns, { memoryWithheld: ctx.memoryWithheld === true }),
+      ...buildPublicClaudePolicyArgs(allowedPatterns, workspaceBwrapSandbox
+        ? { trust: sandboxTrust, allow: grants, memoryWithheld: ctx.memoryWithheld === true }
+        : { memoryWithheld: ctx.memoryWithheld === true }),
       ...(ctx.publicSkillArgs || []),
     ];
   } else if (allowedPatterns.length > 0) {
     innerArgv = [...innerArgv, '--allowedTools', ...allowedPatterns];
   }
+  if (workspaceBwrapSandbox) {
+    // Seatbelt denies writes under .git by path, present or not. A bwrap mount
+    // needs the path to exist, so a writable project without a .git could get
+    // one from the child, hooks included, that the person's next git command
+    // runs. Refuse that rather than create anything in their project.
+    if (grants.includes('write')) {
+      const gitEntry = await statOrNull(join(ctx.cwd, '.git'));
+      if (!gitEntry || gitEntry.isSymbolicLink()) {
+        throw new Error('workspace Claude agents with write on Linux need the project to be a git '
+          + `repository (run \`git init\` in ${ctx.cwd}), so its .git can be held read-only`);
+      }
+    }
+    const claudeBin = resolveClaudePath(claudeEnv);
+    const { statePath } = ctx.publicClaudeState;
+    let claudeInstall = null;
+    try {
+      claudeInstall = dirname(realpathSync(claudeBin));
+    } catch { /* an unresolvable binary fails at spawn with its own error */ }
+    const wrapped = wrapArgvWithBwrap([claudeBin, ...innerArgv], env, {
+      workspacePath: ctx.cwd,
+      workspaceReadOnly: !grants.includes('write'),
+      readOnlyWorkspaceEntries: ['.git'],
+      homePath: statePath,
+      writablePaths: [statePath],
+      readOnlyPaths: [
+        ctx.mcpConfigDir, commitHooksPath, originalHooksPath,
+        ...(ctx.mcpReadDirectories || []),
+        ...(ctx.workspaceGit?.readDirectories || []),
+        ...(ctx.workspaceGit?.readPaths || []),
+      ].filter(Boolean),
+      // The binaries the jail runs: claude (a user-local install is outside
+      // the default binds, and its link points into a versions folder), the
+      // node that runs the stdio MCP servers, and the git the history tool runs.
+      optionalReadOnlyPaths: [...new Set([
+        dirname(claudeBin), claudeInstall, dirname(process.execPath),
+        ctx.workspaceGit ? dirname(ctx.workspaceGit.executable) : null,
+        // A claude not found on PATH is left bare and fails at spawn; its
+        // dirname is '.', which is not a path to bind.
+      ].filter((p) => p && isAbsolute(p)))],
+    });
+    // TASK-440 reads the transcript from the HOME the child wrote under.
+    return { cmd: wrapped[0], args: wrapped.slice(1), env: claudeEnv, childHome: statePath };
+  }
   if (sandboxMode === 'bwrap') {
     const claudeBin = resolveClaudePath(claudeEnv);
     const wrapped = wrapArgvWithBwrap([claudeBin, ...innerArgv], env, {
@@ -974,6 +1111,8 @@ export default {
       && PUBLIC_SANDBOX_MODES.has(resolvePublicSandboxMode(ctx.environment?.sandbox));
     const publicBwrapSandbox = publicTrust
       && resolvePublicSandboxMode(ctx.environment?.sandbox) === 'bwrap';
+    const workspaceBwrapSandbox = ctx.environment?.sandbox?.trust === 'workspace'
+      && resolvePublicSandboxMode(ctx.environment?.sandbox) === 'bwrap';
     try {
       // Trust is normalized at entry (legacy `internal` reads as public). The
       // MCP policy follows trust alone, whatever confines the seat: a public
@@ -981,6 +1120,12 @@ export default {
       // (Rhea on #2247).
       if (publicNativeSandbox) {
         publicClaudeState = await preparePublicClaudeState(ctx);
+      } else if (workspaceBwrapSandbox) {
+        // Checked before the state is prepared, so a host that cannot run the
+        // jail never gets a copy of the login.
+        const bwrap = (ctx._detectBwrap || detectBwrap)();
+        if (!bwrap.available) throw new Error(`workspace Claude agents require bwrap: ${bwrap.error}`);
+        publicClaudeState = await prepareWorkspaceBwrapClaudeState(ctx);
       }
       if (publicTrust) {
         const prompt = await publicSkillPromptArgs(mountedSkills);
diff --git a/cli/src/lib/sandbox/bwrap.js b/cli/src/lib/sandbox/bwrap.js
index 1a967d9c32..d22ea5e53f 100644
--- a/cli/src/lib/sandbox/bwrap.js
+++ b/cli/src/lib/sandbox/bwrap.js
@@ -161,7 +161,29 @@ export const wrapArgvWithBwrap = (innerArgv, env, opts = {}) => {
     flags.push('--ro-bind-try', p, p);
   }
 
-  flags.push('--bind', opts.workspacePath, opts.workspacePath);
+  // A HOME the adapter keeps outside the workspace (a workspace seat's state)
+  // is bound writable on its own, so the child's transcripts and login stay
+  // out of the person's project.
+  for (const p of opts.writablePaths || []) {
+    if (!p || !isAbsolute(p)) {
+      throw new Error('wrapArgvWithBwrap opts.writablePaths entries must be absolute paths');
+    }
+    flags.push('--bind', p, p);
+  }
+
+  flags.push(opts.workspaceReadOnly ? '--ro-bind' : '--bind', opts.workspacePath, opts.workspacePath);
+  // Entries held read-only inside a writable workspace (its .git). Bound after
+  // the workspace so they land on top of it. In a writable workspace a missing
+  // entry cannot be protected — the child could create it, and a planted
+  // .git/hooks runs on the person's next git command — so the bind is strict
+  // there and bwrap fails rather than starts.
+  for (const entry of opts.readOnlyWorkspaceEntries || []) {
+    if (!entry || isAbsolute(entry) || entry.split(/[\\/]/).includes('..')) {
+      throw new Error('wrapArgvWithBwrap opts.readOnlyWorkspaceEntries entries must be relative names inside the workspace');
+    }
+    const p = join(opts.workspacePath, entry);
+    flags.push(opts.workspaceReadOnly ? '--ro-bind-try' : '--ro-bind', p, p);
+  }
   flags.push('--chdir', opts.workspacePath);
   flags.push('--setenv', 'HOME', opts.homePath || opts.workspacePath);