# entity.add_behaviour

> Talos next · Since next

[editor or disk] Attach a behaviour: a script component with module and props, one undo step.

The module is the project's (behaviors/drift for behaviors/drift.ts) or built-in; argus://behaviours lists both with their props.

| | |
|---|---|
| Title | Add a behaviour |
| Mode |  |
| Token cost | about 164 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. |
| `entity` | `string` | yes |  |  |  |
| `module` | `string` | yes |  |  | script.module, such as player or behaviors/drift |
| `props` | `object` | no |  |  | Its settings |
| `save` | `boolean` | no |  |  | `true` saves the scene afterwards. |
| `scene` | `string` | no |  |  | The scene file to act on. The open scene when absent. |

## Example

An MCP `tools/call` with the required arguments (placeholders in angle brackets).

```json
{
  "name": "entity.add_behaviour",
  "arguments": {
    "entity": "<entity>",
    "module": "<module>"
  }
}
```