gitea_mcp_server.py

@@ -159,6 +159,17 @@ if PROJECT_ROOT not in sys.path:
     sys.path.insert(0, PROJECT_ROOT)
 
 import json
+import subprocess
+
+_process_boot_head_sha = None
+try:
+    _process_boot_head_sha = subprocess.run(
+        ["git", "rev-parse", "HEAD"],
+        capture_output=True, text=True, check=True, cwd=PROJECT_ROOT
+    ).stdout.strip()
+except Exception:
+    pass
+
 
 _preflight_whoami_called = False
 _preflight_capability_called = False
@@ -9698,6 +9709,34 @@ def gitea_route_task_session(
     )
 
 
+_restart_triggered = False
+
+
+def _trigger_mcp_auto_restart():
+    global _restart_triggered
+    if _restart_triggered or _preflight_in_test_mode():
+        return
+    _restart_triggered = True
+
+    config_path = os.environ.get(
+        "MCP_CONFIG_PATH",
+        os.path.expanduser("~/.gemini/config/mcp_config.json")
+    )
+
+    try:
+        if os.path.exists(config_path):
+            os.utime(config_path, None)
+    except Exception:
+        pass
+
+    import threading
+    import time
+    def delayed_exit():
+        time.sleep(1.0)
+        os._exit(0)
+    threading.Thread(target=delayed_exit, daemon=True).start()
+
+
 def _check_mcp_runtimes_diagnostics(task: str, matching_profiles: list[str]) -> list[str]:
     """Check running runtimes and return errors if they are missing or stale."""
     import subprocess
@@ -9719,6 +9758,19 @@ def _check_mcp_runtimes_diagnostics(task: str, matching_profiles: list[str]) ->
     except Exception as exc:
         return [f"stale-runtime: failed to list running processes: {exc}"]
 
+    current_head_sha = None
+    try:
+        current_head_sha = subprocess.run(
+            ["git", "rev-parse", "HEAD"],
+            capture_output=True, text=True, check=True, cwd=PROJECT_ROOT
+        ).stdout.strip()
+    except Exception:
+        pass
+
+    git_stale = False
+    if _process_boot_head_sha and current_head_sha and _process_boot_head_sha != current_head_sha:
+        git_stale = True
+
     self_pid = os.getpid()
     self_stale = False
 
@@ -9754,7 +9806,7 @@ def _check_mcp_runtimes_diagnostics(task: str, matching_profiles: list[str]) ->
         if match:
             profile = match.group(1)
 
-        is_stale = start_time < code_mtime
+        is_stale = (start_time < code_mtime) or git_stale
         if pid == self_pid and is_stale:
             self_stale = True
 
@@ -9766,9 +9818,11 @@ def _check_mcp_runtimes_diagnostics(task: str, matching_profiles: list[str]) ->
             }
 
     if self_stale:
+        _trigger_mcp_auto_restart()
         reasons.append(
             "stale-runtime: The active Gitea MCP server process is stale (running code from before changes were merged). "
-            "Please fully restart the Gitea MCP server (e.g. touch /Users/jasonwalker/.gemini/config/mcp_config.json) and retry."
+            "Auto-restart has been triggered: touched mcp_config.json to reload the daemon. "
+            "The current process will cleanly exit shortly."
         )
 
     if matching_profiles:

tests/test_mcp_stale_runtime.py

@@ -67,5 +67,66 @@ class TestMcpStaleRuntime(unittest.TestCase):
         # But does NOT contain missing author profile error
         self.assertFalse(any("None of the matching profiles for task" in r for r in reasons_author))
 
+    @patch("subprocess.run")
+    @patch("os.path.getmtime")
+    @patch("os.path.exists")
+    @patch("os.getpid")
+    @patch.dict("os.environ", {"GITEA_FORCE_MCP_RUNTIME_CHECK": "1"})
+    def test_git_head_change_triggers_staleness(self, mock_getpid, mock_exists, mock_getmtime, mock_run):
+        # Set boot SHA to FAKE1 and current to FAKE2
+        gitea_mcp_server._process_boot_head_sha = "FAKE1"
+        mock_getpid.return_value = 12345
+        mock_exists.return_value = True
+
+        # Code time is in the past (fresh process chronologically)
+        code_time = datetime(2026, 7, 8, 11, 0, 0)
+        mock_getmtime.return_value = code_time.timestamp()
+
+        ps_output = (
+            "  PID LSTART COMMAND\n"
+            "12345 Wed Jul  8 12:00:00 2026 /path/to/python mcp_server.py\n"
+        )
+
+        mock_run_ps = MagicMock()
+        mock_run_ps.stdout = ps_output
+
+        mock_run_env = MagicMock()
+        mock_run_env.stdout = "GITEA_MCP_PROFILE=prgs-author"
+
+        mock_run_git = MagicMock()
+        mock_run_git.stdout = "FAKE2" # different SHA
+
+        def side_effect(args, **kwargs):
+            if args[0] == "ps" and "eww" in args:
+                return mock_run_env
+            elif args[0] == "ps":
+                return mock_run_ps
+            elif args[0] == "git" and "rev-parse" in args:
+                return mock_run_git
+            raise ValueError(f"Unexpected: {args}")
+
+        mock_run.side_effect = side_effect
+
+        # Stale even though process started AFTER code mtime, because git HEAD changed
+        reasons = gitea_mcp_server._check_mcp_runtimes_diagnostics("create_issue", ["prgs-author"])
+        self.assertTrue(any("stale-runtime: The active Gitea MCP server process is stale" in r for r in reasons))
+
+    @patch("threading.Thread")
+    @patch("os.utime")
+    @patch("os.path.exists")
+    @patch.dict("os.environ", {"MCP_CONFIG_PATH": "/tmp/mcp_config.json"})
+    def test_auto_restart_trigger_touches_and_spawns(self, mock_exists, mock_utime, mock_thread):
+        mock_exists.return_value = True
+        gitea_mcp_server._restart_triggered = False
+
+        # Ensure we are not skipped in test mode for testing purposes
+        with patch("gitea_mcp_server._preflight_in_test_mode", return_value=False):
+            gitea_mcp_server._trigger_mcp_auto_restart()
+
+        mock_utime.assert_called_once_with("/tmp/mcp_config.json", None)
+        mock_thread.assert_called_once()
+        self.assertTrue(gitea_mcp_server._restart_triggered)
+
+
 if __name__ == "__main__":
     unittest.main()