# studio-world-outside-match

> An action changes the world in a row that can run while no match is running.

| | |
| --- | --- |
| Kind | Studio problem |
| Reported by | Studio validation: the Problems panel, Play, Publish and the MCP `validate` tool |
| Code in the Studio | `world-outside-match` |

The world (discs, walls, the camera) exists only during a match. Rows for players joining, chat or UI requests can run while the room waits. An action that touches the world there would fail.

## Fix

- Add the condition `match ≠ ready` to the row.
- Move the action into a row that only runs during a match.

## See also

- [Problems and validation](/studio/playtesting)