# create

URL: /business/nouns/flag/create · Id: `verb:Flag.create` · Call: `await $.Flag.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 Flag.

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

## Inputs
| Input | Type | Required | Description |
| --- | --- | --- | --- |
| `key` | `string` | Yes | The name code reads. |
| `rules` | `json` | No | Who gets which value, including percentage splits. |

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

## Effects
- Emits `Flag.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. | [Flag.create](/business/nouns/flag/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 flag to TutorLoop.
```

**API**

```bash
curl -X POST https://api.sb/tutorloop.com/flags \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"key":"new-checkout"}'
```

```json
{
  "api": "https://api.sb/tutorloop.com",
  "flag": {
    "$id": "https://api.sb/tutorloop.com/flags/flag_1",
    "$type": "Flag",
    "key": "new-checkout"
  },
  "action": {
    "$id": "https://api.sb/tutorloop.com/actions/action_1",
    "operation": "Flag.create",
    "status": "done"
  },
  "links": {
    "self": "https://api.sb/tutorloop.com/actions/action_1"
  }
}
```

**SDK**

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

const flag = await $.Flag.create({ key: 'new-checkout' })
```

**CLI**

```bash
npx startup-builder do Flag.create --json '{"key":"new-checkout"}'
```

**MCP**

```json
{
  "name": "do",
  "arguments": {
    "code": "return await $.Flag.create({ key: 'new-checkout' })"
  }
}
```