feat(cli): dimos restart command (DIM-683)

[spomichter]

Summary

Adds dimos restart command that stops the running DimOS instance and re-invokes with the same arguments.

Supersedes #1445 (which targeted the now-merged daemon branch and referenced removed _stop_entry function).

Usage

dimos restart          # graceful stop + restart
dimos restart --force  # SIGKILL + restart

How it works

1. Reads the most recent alive run from the registry
2. Saves its original_argv (exact sys.argv from the original run)
3. Calls stop_entry() (SIGTERM or SIGKILL with --force)
4. Waits for old process to fully exit (up to 2s poll)
5. Uses os.execvp() to replay the original command

No CLI flag reconstruction — just replays sys.argv verbatim. If the original run used --daemon, the restart inherits it automatically.

Changes

• dimos/core/run_registry.py: Add original_argv field to RunEntry (+1 line)
• dimos/robot/cli/dimos.py: Store sys.argv in RunEntry, add restart command (+30 lines)

Related

• Closes DIM-683
• Depends on daemon mode from feat(cli): daemon mode, stop, status, per-run logs (DIM-681, DIM-682, DIM-684, DIM-685) #1436 (merged)
• Supersedes feat(cli): dimos restart command (DIM-683) #1445

Contributor License Agreement

• I have read and approved the CLA

[greptile-apps]

Greptile Summary

This PR implements dimos restart, a CLI command that stops the currently-running DimOS instance and re-executes it with the exact original sys.argv using os.execvp. The approach is clean — it avoids fragile CLI-flag reconstruction by persisting the raw argument vector in a new original_argv field on RunEntry.

Key points:

• original_argv has a default factory (list), so existing registry files without the field still deserialize correctly and are caught by the explicit if not entry.original_argv guard.
• Both daemon and non-daemon RunEntry creation paths now capture sys.argv, which means --daemon is naturally inherited on restart without any special handling.
• OSError from os.execvp is caught and reported cleanly, with a poll loop that waits up to 2 s after the stop signal before exec-ing the new process.
• The wait loop runs after stop_entry() (which already implements its own 5-second timeout and SIGKILL escalation), providing defense-in-depth process synchronization.

Confidence Score: 5/5

• PR is safe to merge. No functional issues or gaps identified.
• The implementation is well-structured with proper error handling, backward compatibility, and defensive synchronization. All critical paths are handled: original_argv uses safe defaults for deserialization, OSError from os.execvp is caught and reported cleanly, and a post-stop poll ensures the old process has exited before the new one starts. Both daemon and non-daemon code paths correctly capture sys.argv, ensuring --daemon is naturally inherited on restart without special handling.
• No files require special attention.

_{Last reviewed commit: 7406c2c}

[greptile-apps]

Boolean False config overrides are silently dropped on restart.

When a boolean config override is explicitly False (e.g., the original run was started with --no-verbose or another --no-<flag> style option), the current code only appends --<flag> for True values and appends nothing for False, causing the --no-<flag> form to be lost when reconstructing the command.

Looking at create_dynamic_callback() (lines 65-77), boolean GlobalConfig fields use the --flag/--no-flag Typer pattern. Any False override stored in config_overrides must emit --no-<flag> to preserve the original invocation.

Suggested change

	if isinstance(value, bool):
	if value:
	cmd.append(flag)
	else:
	if isinstance(value, bool):
	if value:
	cmd.append(flag)
	else:
	cmd.append(f"--no-{key.replace('_', '-')}")

[spomichter]

@greptile

[greptile-apps]

Unhandled OSError from os.execvp

os.execvp raises FileNotFoundError (a subclass of OSError) if argv[0] is not found on PATH, and PermissionError if it is not executable. Since the old instance has already been stopped at this point, an unhandled exception here leaves the system with nothing running and exposes a raw Python traceback to the user instead of a clean error message.

Suggested change

	os.execvp(argv[0], argv)
	try:
	os.execvp(argv[0], argv)
	except OSError as exc:
	typer.echo(f"Error: failed to restart — {exc}", err=True)
	raise typer.Exit(1)

[greptile-apps]

No wait after SIGKILL before exec in force mode

When --force is used, stop_entry sends SIGKILL and returns immediately without waiting for the old process to exit. os.execvp then runs the new dimos run which will call check_port_conflicts(). Because entry.remove() has already been called inside stop_entry, the registry check passes, but the underlying gRPC port may still be transiently held by the dying process. In practice SIGKILL is near-instantaneous on Linux, but a small polling wait before exec would make the force path as robust as the SIGTERM path (which already waits up to 5 s):

    msg, _ok = stop_entry(entry, force=force)
    typer.echo(f"  {msg}")

    # For SIGKILL the port is released almost immediately, but a brief
    # poll ensures the new run's port-conflict check never races the old process.
    from dimos.core.run_registry import is_pid_alive
    for _ in range(20):          # up to 2 s
        if not is_pid_alive(entry.pid):
            break
        time.sleep(0.1)

    typer.echo(f"  Running: {' '.join(argv)}")
    os.execvp(argv[0], argv)

[greptile-apps]

--daemon usage in PR description is unimplemented

The PR description explicitly advertises dimos restart --daemon as a supported invocation, but the restart command only declares a --force / -f option. Running dimos restart --daemon today produces a Typer "Unexpected option" error.

If background restart is genuinely desired, a --daemon flag needs to be added here (and os.execvp replaced with a subprocess spawn for that code path). If the feature is out of scope for this PR the description should be corrected to avoid user confusion.

[spomichter]

@greptile

[Dreamsorcerer]

Very minor suggestion, but it might be good to make these kind of things immutable in future generally. This also avoids needing the default_factory:

Suggested change

	original_argv: list[str] = field(default_factory=list)
	original_argv: Sequence[str] = ()