# create

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

> Creates a Message.

Create makes a new [Message](/business/nouns/message) from the inputs below. It is inherited: every [Noun](/business/nouns/noun) has `get`, `list`, `create`, `update` and `delete`.

## Inputs
| Input | Type | Required | Description |
| --- | --- | --- | --- |
| `medium` | `string` | Yes | One of `email`, `sms`, `voice`, or `chat`. |
| `direction` | `string` | Yes | One of `inbound` or `outbound`. |
| `body` | `text` | Yes | What it says. |
| `from` | `string` | No | The sender: an address, a number, or a Channel id. |
| `to` | `string` | No | The recipient: an address, a number, or a Person id. |
| `subject` | `string` | No | The subject line, for email. |
| `purpose` | `string` | No | Why it goes out, such as onboarding; consent and suppression rules read it. |
| `sequence` | [Sequence](/business/nouns/sequence) | No | A Sequence sends Messages, each at its own step and wait. |
| `channel` | [Channel](/business/nouns/channel) | No | Every Message flows through one Channel. |
| `thread` | [Thread](/business/nouns/thread) | No | A Thread groups Messages that reply to one another. |

## Outputs
| Output | Type | Required | Description |
| --- | --- | --- | --- |
| `message` | [Message](/business/nouns/message) | Yes | The Message. |

## Effects
- Emits `Message.created`.
- Two-way: `try`, `send`, `do`.

## 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. | [Message.create](/business/nouns/message/create) |

## 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
Add a message to LedgerLark.
```

**API**

```bash
curl -X POST https://api.sb/ledgerlark.com/messages \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"medium":"email","direction":"inbound","body":"Example body"}'
```

```json
{
  "api": "https://api.sb/ledgerlark.com",
  "message": {
    "$id": "https://api.sb/ledgerlark.com/messages/message_1",
    "$type": "Message",
    "medium": "email",
    "direction": "inbound",
    "body": "Example body"
  },
  "action": {
    "$id": "https://api.sb/ledgerlark.com/actions/action_1",
    "operation": "Message.create",
    "status": "done"
  },
  "links": {
    "self": "https://api.sb/ledgerlark.com/actions/action_1"
  }
}
```

**SDK**

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

const message = await $.Message.create({ medium: 'email', direction: 'inbound', body: 'Example body' })
```

**CLI**

```bash
npx startup-builder do Message.create --json '{"medium":"email","direction":"inbound","body":"Example body"}'
```

**MCP**

```json
{
  "name": "do",
  "arguments": {
    "code": "return await $.Message.create({ medium: 'email', direction: 'inbound', body: 'Example body' })"
  }
}
```