# lock

URL: /business/nouns/period/lock · Id: `verb:Period.lock` · Call: `await $.Period.lock({ … })` (SDK) or the `do` tool at `https://api.sb/mcp`. Inputs says what to pass, Outputs what returns, When it waits who approves.

> Lock seals a closed Period, so any later correction posts to the next open Period.

Lock seals a closed [Period](/business/nouns/period), so any later correction posts to the next open Period.

## Inputs
| Input | Type | Required | Description |
| --- | --- | --- | --- |
| `period` | [Period](/business/nouns/period) | Yes | The closed Period. |

## Outputs
| Output | Type | Required | Description |
| --- | --- | --- | --- |
| `period` | [Period](/business/nouns/period) | Yes | The locked Period. |

## Effects
- Emits [`Period.locked`](/business/events/Period.locked).
- Performed by the [Finance Lead](/agents/finance/finance-lead).
- One-way (money): it waits out its delay window, and runs in the `send` and `do` modes.

## Refuses when
| Check | Error | Fix | Then call |
| --- | --- | --- | --- |
| The key is valid, but its scopes do not allow this operation. | [`forbidden`](/code/api/errors/forbidden) | Use a key whose scopes cover the operation, or ask an owner of the namespace to grant them. | [Period.lock](/business/nouns/period/lock) |
| The record is not in a state that allows this Verb, so the call is refused. | [`refused`](/code/api/errors/refused) | Read the record, run the Verb that moves it to an allowed state, then retry. | [Period.lock](/business/nouns/period/lock) |

## When it waits
| Gate | Default |
| --- | --- |
| Decision class | Medium: one-way, bounded (money) |
| [Delay window](/systems/trust-and-governance/controls/one-way-windows) | 1 business hour, in which a watcher can pause, redirect or cancel it; then it runs. |
| Limit | The spend [Limit](/business/nouns/limit) of the [Permission](/business/nouns/permission) or [Mandate](/business/nouns/mandate) it runs under. |
| Over the Limit | It waits `pending` for an [Approval](/business/nouns/approval) from the [Founder](/agents/founding/founder). Approved, it runs; refused, it ends `refused` with [`limit-exceeded`](/code/api/errors/limit-exceeded); unanswered by its deadline, it ends `canceled`. |

## Example

**Ask**

```text
Lock the latest period.
```

**API**

```bash
curl -X POST https://api.sb/kilnbakery.com/periods/period_1/lock \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY"
```

```json
{
  "api": "https://api.sb/kilnbakery.com",
  "period": {
    "$id": "https://api.sb/kilnbakery.com/periods/period_1",
    "$type": "Period",
    "month": "2026-10-22",
    "status": "Locked"
  },
  "action": {
    "$id": "https://api.sb/kilnbakery.com/actions/action_1",
    "operation": "Period.lock",
    "status": "done"
  },
  "links": {
    "self": "https://api.sb/kilnbakery.com/actions/action_1"
  }
}
```

**SDK**

```ts
import { $ } from 'startup-builder'

const period = await $.Period.lock({ period: 'period_1' })
```

**CLI**

```bash
npx startup-builder do Period.lock --json '{"period":"period_1"}'
```

**MCP**

```json
{
  "name": "do",
  "arguments": {
    "code": "return await $.Period.lock({ period: 'period_1' })"
  }
}
```