Replay

Replay mode lets you save a run and inspect it later without re-running the crew.

Save a Run

lantern play /path/to/project --name demo-run

This writes:

.lantern_replays/demo-run.jsonl

Named runs auto-start. The start overlay is skipped.

If you start Play without --name, the UI asks for a run name before START and uses that name for the saved replay.

Replay by Name

From the same project root:

lantern replay demo-run

Replay the Latest Run

From the same project root:

lantern replay last

last selects the newest .jsonl file in .lantern_replays/.

Replay by Path

lantern replay /path/to/.lantern_replays/demo-run.jsonl

Playback Speed

lantern replay demo-run --speed 2.0

UI Controls

Replay mode adds controls for:

• pause/resume,
• speed,
• seek,
• restart,
• stop.

When to Use Replay

Replay is useful for:

• demos,
• debugging a run after it finished,
• comparing UI behavior without spending tokens again,
• sharing a deterministic reproduction with another developer.