[codex] Fix stale AIO sandbox cache reuse (#3494)

* Fix stale AIO sandbox cache reuse

* Address AIO sandbox review feedback

* Distinguish sandbox health check failures

* Keep local discovery recoverable when the runtime check fails

LocalContainerBackend.discover() shares _is_container_running, which now
raises on transient daemon errors instead of returning False. Discovery has
no exception handling in _discover_or_create_with_lock(_async), so a brief
Docker hiccup turned a recoverable "could not verify, create instead" into a
hard acquire failure. Catch the check failure inside discover() and return
None so an unverifiable container is simply not adopted, restoring the
pre-change fall-through while keeping raise-on-unknown semantics protecting
the destroy path.

Reported by fancy-agent on PR #3494.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* Narrow the not-found match in container inspect error handling

A bare "not found" substring also matches transient failures like "command
not found" or "context not found", which would misclassify a check error as
"container definitely gone" and bypass the raise-on-unknown contract. Keep
Docker's specific "No such object"/"No such container" phrases, and only
trust a generic "not found" (Apple Container) when the message names the
inspected container or refers to a container/object.

Reported by WillemJiang on PR #3494.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

backend/tests/test_aio_sandbox_local_backend.py

@@ -1,7 +1,10 @@
 import logging
 import os
+import subprocess
 from types import SimpleNamespace
 
+import pytest
+
 from deerflow.community.aio_sandbox.local_backend import (
     LocalContainerBackend,
     _format_container_command_for_log,
@@ -234,3 +237,99 @@ def test_start_container_keeps_apple_container_port_format(monkeypatch):
     captured_cmd = _capture_start_container_command(monkeypatch, backend, runtime="container")
 
     assert captured_cmd[captured_cmd.index("-p") + 1] == "18080:8080"
+
+
+def _backend_for_inspect_tests() -> LocalContainerBackend:
+    backend = LocalContainerBackend(
+        image="sandbox:latest",
+        base_port=8080,
+        container_prefix="sandbox",
+        config_mounts=[],
+        environment={},
+    )
+    backend._runtime = "docker"
+    return backend
+
+
+def test_is_container_running_false_when_container_missing(monkeypatch):
+    backend = _backend_for_inspect_tests()
+
+    def fake_run(cmd, **kwargs):
+        return SimpleNamespace(stdout="", stderr="Error: No such object: sandbox-missing", returncode=1)
+
+    monkeypatch.setattr("subprocess.run", fake_run)
+
+    assert backend._is_container_running("sandbox-missing") is False
+
+
+def test_is_container_running_raises_on_runtime_error(monkeypatch):
+    backend = _backend_for_inspect_tests()
+
+    def fake_run(cmd, **kwargs):
+        return SimpleNamespace(stdout="", stderr="Cannot connect to the Docker daemon", returncode=1)
+
+    monkeypatch.setattr("subprocess.run", fake_run)
+
+    with pytest.raises(RuntimeError, match="Failed to inspect container sandbox-busy"):
+        backend._is_container_running("sandbox-busy")
+
+
+def test_is_container_running_raises_on_timeout(monkeypatch):
+    backend = _backend_for_inspect_tests()
+
+    def fake_run(cmd, **kwargs):
+        raise subprocess.TimeoutExpired(cmd=cmd, timeout=kwargs["timeout"])
+
+    monkeypatch.setattr("subprocess.run", fake_run)
+
+    with pytest.raises(RuntimeError, match="Timed out checking container sandbox-timeout"):
+        backend._is_container_running("sandbox-timeout")
+
+
+def test_discover_returns_none_when_runtime_check_fails(monkeypatch):
+    """A transient daemon error during discovery must fall through to create, not fail acquire."""
+    backend = _backend_for_inspect_tests()
+
+    def fake_run(cmd, **kwargs):
+        return SimpleNamespace(stdout="", stderr="Cannot connect to the Docker daemon", returncode=1)
+
+    monkeypatch.setattr("subprocess.run", fake_run)
+
+    assert backend.discover("sandbox-blip") is None
+
+
+def test_discover_returns_none_when_runtime_check_times_out(monkeypatch):
+    """An inspect timeout during discovery must not propagate out of discover()."""
+    backend = _backend_for_inspect_tests()
+
+    def fake_run(cmd, **kwargs):
+        raise subprocess.TimeoutExpired(cmd=cmd, timeout=kwargs["timeout"])
+
+    monkeypatch.setattr("subprocess.run", fake_run)
+
+    assert backend.discover("sandbox-timeout") is None
+
+
+def test_is_container_running_false_on_apple_container_not_found(monkeypatch):
+    """Apple Container's generic "not found" is trusted when it names the container."""
+    backend = _backend_for_inspect_tests()
+
+    def fake_run(cmd, **kwargs):
+        return SimpleNamespace(stdout="", stderr='Error: not found: "sandbox-apple"', returncode=1)
+
+    monkeypatch.setattr("subprocess.run", fake_run)
+
+    assert backend._is_container_running("sandbox-apple") is False
+
+
+def test_is_container_running_raises_on_unrelated_not_found_error(monkeypatch):
+    """Transient errors whose text contains "not found" must not be misread as a dead container."""
+    backend = _backend_for_inspect_tests()
+
+    def fake_run(cmd, **kwargs):
+        return SimpleNamespace(stdout="", stderr="Error: credential helper not found in $PATH", returncode=1)
+
+    monkeypatch.setattr("subprocess.run", fake_run)
+
+    with pytest.raises(RuntimeError, match="Failed to inspect container sandbox-busy"):
+        backend._is_container_running("sandbox-busy")