play.start
Since next
Play the open scene in the editor; waits until it runs.
It runs the newest READY BUILD: a file you just wrote is applied and built first (several files wait for build.apply; settled says which). A build with unchecked TypeScript is refused. Agents sharing the editor play one at a time: busy is your place in line; a 5-minute lease passes Play on. A sub-agent that passes agent plays in its own editor.
| Title | Play |
| Mode | editor |
| Token cost | about 223 tokens (in the default list, paid on every call) |
| Toolset | core |
Arguments
| Argument | Type | Required | Default | Allowed values | Description |
|---|---|---|---|---|---|
agent | string | no | The name of the agent making the call, when several agents share one connection: each named agent is its own actor and plays its own game. Leave it out when there is one agent. | ||
saveFirst | boolean | no | true | Save unsaved edits first (default) so their checked build plays. false plays the unsaved scene in memory, unverified, writing nothing | |
scene | string | no | A named agent's scene, in its own editor; absent: its open scene, else the editor's |
Example
An MCP tools/call with the required arguments (placeholders in angle brackets).
{
"name": "play.start",
"arguments": {}
}