> ## 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_checkout

> Place and pay for the current cart with a one-time card

Places and pays for the current cart at a linked merchant: it runs the spend gate, mints a one-time card sized to the cart total, and places the order. This is destructive, so confirm the cart and total with the user first.

<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                                                                        |
| ----------------- | ------ | -------- | ---------------------------------------------------------------------------------- |
| `merchant`        | string | Yes      | Merchant slug (for example `doordash`)                                             |
| `tip_cents`       | number | No       | Optional tip in cents; added to the charge and the minted card size                |
| `delivery_time`   | string | No       | ISO-8601 time to schedule delivery for; omit for ASAP                              |
| `approval_id`     | string | No       | A previously issued spend approval id, if checkout returned `needs_approval`       |
| `idempotency_key` | string | No       | A stable key for this purchase; reuse it on every retry so it never double-charges |

## Returns

On success, an order confirmation with the merchant order id, the charged total, and the last four digits of the one-time card (test-mode orders are flagged as no real charge). If a spend approval is required you get `needs_approval` with an approval id to retry with; if the spend gate blocks it you get `denied` with the reason. A `pending` result means the order is placed and only the payment is still confirming: call again with the same `idempotency_key` to re-check, never with a fresh one.

## Example

```json theme={null}
{ "name": "buy_checkout", "arguments": { "merchant": "doordash", "tip_cents": 500, "idempotency_key": "9c2e6f4a-1b7d-4e2a-9a3f-5d8c0b1e2f37" } }
```