---
title: "tool si.act.beat"
description: "what runs, and when: the beat."
section: reference
address: /reference/tools/si-act-beat
contract: 0476e35e6e275db5
---

# tool si.act.beat

what runs, and when: the beat.

[figure: Over MCP, si.act.beat takes BeatInput and returns a card whose body is Beat.]

the beat. The call needs the act grant at the strategy rung.



| | |
|---|---|
| input | [BeatInput](/concepts/beatinput) |
| result | a card whose body is [Beat](/concepts/beat) |
| read-only | no |
| destructive | yes |
| card address | `ui://scale-intelligence/cards/Beat` |
| HTTP route | [`/v1/act/beat`](/reference/act/beat) |





| field | type | required | note |
|---|---|---|---|
| `beat` | [Beat](/concepts/beat) | yes |  |