> ## Documentation Index
> Fetch the complete documentation index at: https://docs.agentcard.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# buy_set_budget

> Set a spending budget enforced before every checkout

Sets a spending budget that the spend gate enforces before any checkout mints a card. Use it to cap how much an agent can spend per day, week, month, or in total.

<Note>Not advertised in `tools/list` by default — the [buy](/companies/mcp/tools/buy) tool covers this conversationally. Expert integrations can still call it by name.</Note>

## Parameters

| Parameter     | Type   | Required | Description                                       |
| ------------- | ------ | -------- | ------------------------------------------------- |
| `period`      | string | Yes      | One of `daily`, `weekly`, `monthly`, or `total`   |
| `limit_cents` | number | Yes      | Budget cap in cents                               |
| `timezone`    | string | No       | IANA timezone for window boundaries (default UTC) |

## Returns

A confirmation with the cap in dollars, the period, and the timezone it applies in, for example "Budget set: \$100.00 per weekly (UTC)". Failures return a short error message.

## Example

```json theme={null}
{ "name": "buy_set_budget", "arguments": { "period": "weekly", "limit_cents": 10000 } }
```