Watch operator parameter changes
watch_parameter_changesSubscribe to parameter change events on TouchDesigner operators. Use watch to register, unwatch to remove, and list to see active subscriptions.
Instructions
Opt-in: subscribe to param.changed events for an operator's parameters. When a watched parameter's value changes in TouchDesigner (by a human or a script), the bridge broadcasts a {path, par, prev, value, frame} event on the TD event stream, forwarded to the MCP client as a logging notification. Use action='watch' to register (optionally scoped to named parameters), 'unwatch' to remove, and 'list' to see active watches. Events only arrive when the server's TD event stream is enabled (TDMCP_EVENTS); param.changed is treated as a high-frequency event (coalesced bridge-side so a slider drag can't flood). Survives TDMCP_BRIDGE_ALLOW_EXEC=0.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| path | No | Operator path to watch for parameter changes, e.g. /project1/level1. Required for action='watch'/'unwatch'; omit for action='list'. | |
| action | No | 'watch' registers a subscription, 'unwatch' removes it (or just the named parameters), 'list' returns all active watches. | watch |
| parameters | No | Optional list of parameter names to watch (e.g. ['opacity','level']). Omit to watch every parameter on the operator. |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| path | No | The canonical operator path (for watch/unwatch). | |
| count | No | Number of active watches (for the 'list' action). | |
| action | Yes | The action that was performed: watch, unwatch, or list. | |
| watches | No | Every active watch (for the 'list' action). | |
| watching | No | Whether an active watch remains on this op after the action. | |
| parameters | No | Parameters now watched on this op, or null for a watch-all subscription. |