# POST /api/v2/labels

Create a label

- MCP id: labels.store
- Scope: api:write:project_management
- Permission: project_management::manage_work_items
- Needs the sprints feature on your organisation
- Rate cost: 1 unit, write bucket. A write costs the same whatever `view` you ask for.
- Cache-Control: private, no-store

Creates a label on a project and returns it with a `Location` header.

`color` is optional: omit it and the server picks the first palette colour the project does not already use. `order` is not accepted: the new label is placed last within its project and is reordered only by dragging it in plnnrly. Attach the label to work items from the work-item side, with `label_ids`.

## Parameters
- view (string, optional): Which field set to render.
- X-Request-Id (header, optional): A correlation id of your own. It is recorded in our logs next to the server's request id but never returned: the response header always carries the server's id. A value that does not match the pattern is discarded silently, never rejected.
- Idempotency-Key (header, optional): A caller-chosen key that makes this POST safe to retry. Replaying it returns the original response with Idempotency-Replayed: true.

## Request body
- project_id (integer → Project.id, required): The project this label belongs to. Follow `GET /api/v2/projects/{project}` for its details; the project is not expandable from here.
- name (string ≤ 255, required): Label name as shown on the chip, e.g. `Blocked`.
- color (string ≤ 255, optional): Six-digit hex colour, e.g. `#ef4444`. Stored verbatim: a row written before the colour picker enforced the format reads back as it is stored.
- icon (string or null ≤ 255, optional): Icon name, e.g. `heroicon-o-tag`: not a URL and not markup. Null when the label has no icon.

Unknown keys are refused with `422` validation-failed, naming the key.

## Response 201
- id (integer, required): Unique identifier.
- project_id (integer, required): The project this label belongs to. Follow `GET /api/v2/projects/{project}` for its details; the project is not expandable from here.
- name (string ≤ 255, required): Label name as shown on the chip, e.g. `Blocked`.
- color (string ≤ 255, required): Six-digit hex colour, e.g. `#ef4444`. Stored verbatim: a row written before the colour picker enforced the format reads back as it is stored.
- icon (string or null ≤ 255, required): Icon name, e.g. `heroicon-o-tag`: not a URL and not markup. Null when the label has no icon.
- order (integer, required, server-assigned): Display position within the project. Assigned on create as the next position in that project's label order, changed only by dragging in plnnrly, and not writable.
- created_at (timestamp (YYYY-MM-DDThh:mm:ssZ), required): Creation timestamp.
- updated_at (timestamp (YYYY-MM-DDThh:mm:ssZ), required): Last-write timestamp; use for incremental sync.
- links (LabelLinks, required)
  - self (url, required): The canonical URI of this record.

## Errors
- 403 forbidden-by-policy | insufficient-permission | insufficient-token-scope: Forbidden.
- 409 idempotency-key-in-flight | idempotency-key-reused: Conflict.
- 415 unsupported-media-type: Unsupported media type.
- 422 unprocessable-relationship | validation-failed: Unprocessable content.
- 400 idempotency-key-required | invalid-cursor | invalid-query-parameter | malformed-request | unsupported-parameter: Bad request.
- 401 token-expired | unauthenticated: Unauthenticated.
- 404 endpoint-not-found | resource-not-found: Not found.
- 406 not-acceptable: Not acceptable.
- 429 rate-limit-exceeded: Too many requests.
- 500 internal-error: Server error.
- 503 tenant-unavailable: Service unavailable.

## Example
```bash
curl -X POST \
  'https://<your-url>/api/v2/labels' \
  -H 'Authorization: Bearer <token>' \
  -H 'Accept: application/json' \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: <key>' \
  -d '{
    "project_id": 1,
    "name": "Blocked"
  }'
```