# attend

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

> Attend records that a registered Contact joined the Gathering; an online room calls it on join.

Attend records that a registered person joined the [Gathering](/business/nouns/gathering); an online room calls it when the person joins.

## Inputs
| Input | Type | Required | Description |
| --- | --- | --- | --- |
| `registration` | [Registration](/business/nouns/registration) | Yes | The Registration of the Contact who joined. |

## Outputs
| Output | Type | Required | Description |
| --- | --- | --- | --- |
| `registration` | [Registration](/business/nouns/registration) | Yes | The Registration, now `attended`. |

## Effects
- Emits [`Registration.attended`](/business/events/Registration.attended).
- Performed by the [Marketing Lead](/agents/marketing/marketing-lead).
- Two-way: it runs at once, in the `try`, `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. | [Registration.attend](/business/nouns/registration/attend) |

## When it waits
| Gate | Default |
| --- | --- |
| Decision class | Low: two-way, nothing at stake |
| [Delay window](/systems/trust-and-governance/controls/one-way-windows) | None: it runs once review passes. |
| Limit | The call [Limit](/business/nouns/limit) of the [Permission](/business/nouns/permission) 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
Attend the latest registration.
```

**API**

```bash
curl -X POST https://api.sb/shiftnote.app/registrations/registration_1/attend \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY"
```

```json
{
  "api": "https://api.sb/shiftnote.app",
  "registration": {
    "$id": "https://api.sb/shiftnote.app/registrations/registration_1",
    "$type": "Registration",
    "status": "attended"
  },
  "action": {
    "$id": "https://api.sb/shiftnote.app/actions/action_1",
    "operation": "Registration.attend",
    "status": "done"
  },
  "links": {
    "self": "https://api.sb/shiftnote.app/actions/action_1"
  }
}
```

**SDK**

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

const registration = await $.Registration.attend({ registration: 'registration_1' })
```

**CLI**

```bash
npx startup-builder do Registration.attend --json '{"registration":"registration_1"}'
```

**MCP**

```json
{
  "name": "do",
  "arguments": {
    "code": "return await $.Registration.attend({ registration: 'registration_1' })"
  }
}
```