# GET /api/v2/furlough-balance-mutations/{furlough_balance_mutation}

Read a furlough balance mutation

- MCP id: furlough-balance-mutations.show
- Scope: api:read:furlough
- Permission: none, the record's own rules still apply
- Rate cost: 1 unit, read bucket.
- Cache-Control: private, no-store

Returns one mutation.

The summary and detail views are identical on this resource: every field is small enough for a list row. `user` renders as an `{"id": N}` reference; `?include=user` expands it, and that expansion additionally requires `users::read` and a token scope covering the users prefix. `acceptor_id` has no relation to expand: look the approver up with `GET /api/v2/users/{user}`. As on the list operation, the furlough prefix has no read permission, so another employee's mutation answers `404`, never `403`, unless the caller holds `furlough::view_all` or `furlough::manage`.

## Parameters
- furlough_balance_mutation (integer, path): The FurloughBalanceMutation's numeric id.
- 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.
- If-None-Match (header, optional): The ETag a read is conditional on. A match is answered 304 with no body.

## Response 200
- id (integer, required): Unique identifier.
- user_id (integer, required, server-assigned): The employee this mutation belongs to. Always the authenticated user on create and not writable.
- acceptor_id (integer or null, required, server-assigned): The user who approved this mutation, set by the server when the mutation resolves to approved. Null while it is pending, and left `null` by a denial. Resolve the name through `GET /api/v2/users/{user}`.
- year (integer, required): The balance year this mutation counts against. It is not derived from `start`: every balance sum counts by this year, so a mutation whose period moves into another year keeps counting against the year sent here until `year` is sent too.
- type (string, required): Which leave balance this mutation moves. Regular and special leave are separate balances and never offset one another.
- minutes (integer, required): The signed balance delta in minutes. Negative consumes balance (a leave request); positive grants it (a manager's adjustment, which requires the `furlough::manage` permission to write). The API never computes this from the employee's working week or the organisation's free days: send the exact number of minutes you mean.
- start (timestamp (YYYY-MM-DDThh:mm:ssZ), required): Start of the period this mutation covers, in UTC. Equal to `end` on a manual balance adjustment, which covers no period at all.
- end (timestamp (YYYY-MM-DDThh:mm:ssZ), required): End of the period this mutation covers, in UTC. Never before `start`, and equal to it on a manual balance adjustment.
- description (string, required, multiline): The employee's or manager's own words for this mutation: the reason for the leave, or what the adjustment is for. The only field `?q=` searches.
- is_approved (boolean or null, required): Approval state, in three values: `null` means pending approval, `true` approved, `false` denied. The balance counts pending and approved mutations alike and ignores denied ones. Writing this field at all requires the `furlough::manage` permission.
- user (Ref or UserSummary, required): The employee this mutation belongs to. Expanding it with `?include=user` additionally requires the `users::read` permission and a token scope covering the users prefix.
- 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 (FurloughBalanceMutationLinks, required)
  - self (url, required): The canonical URI of this record.

## Errors
- 403 forbidden-by-policy | insufficient-permission | insufficient-token-scope: Forbidden.
- 304 : Not modified.
- 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 -G \
  'https://<your-url>/api/v2/furlough-balance-mutations/1' \
  --data-urlencode 'include=user' \
  -H 'Authorization: Bearer <token>' \
  -H 'Accept: application/json'
```