# Replay an episode

Send recorded actions back to Sourccey and validate the dataset before training.

Execution context: Controller computer; robot host must be prepared separately.

> Verification pending: existing website examples have not completed a pinned-source or physical-hardware walkthrough. Confirm software version, hardware revision, and actual stopping procedure. Do not assume emergency-stop or release-to-stop behavior. Explicit human approval and supervision are required before physical movement.

## Prepare for replay

- Clear the full robot workspace.
- Keep the emergency stop within reach.
- Start sourccey-host on the robot computer.
- Restore the same physical setup used while recording.

## Replay an episode

Run this on the controller. Episode numbers are zero-based, so 0 is the first recording.

```shell
uv run lerobot-replay --robot.type=sourccey_client --robot.id=sourccey --robot.remote_ip=192.168.1.243 --dataset.repo_id=vulcan-studio/sourccey-demo-1 --dataset.episode=0
```

## Validate the episode

- The action sequence is smooth and recognizable.
- Arms, base, and lift move as recorded.
- The robot stops when replay finishes.
- There is no unexpected or unsafe motion.

Do not train if replay exposes incorrect feature mapping, unexpected lift behavior, or unsafe motion.

Website: https://vulcanrobotics.ai/docs/lerobot/replay

Upstream reference (unpinned): https://github.com/vulcan-forge/lerobot-vulcan/blob/main/docs/sourccey/04-replay.md