# hours.details.save

Save custom field values for one of your own draft or returned time entries. Fill a time entry's required custom fields here before submitting it (hours.form lists them).

`POST /api/v1/contractor/hours.details.save`

Permissions: `contractor:read`, `contractor:write` · Roles: contractor · Idempotency key required · Send `expectedRevision`

MCP tool: `contractor_hours_details_save`

## Fields

| Field | Type | Required | Notes |
| --- | --- | --- | --- |
| `hoursId` | string (ID) | Yes | The ID of the related record. |
| `expectedRevision` | integer or null |  | The record's current revision, from the last time you read it. If someone changed the record since, the request is refused with a conflict so you can reload and check before trying again. |
| `idempotencyKey` | string | Yes | Any unique text you generate once per intended change, so a retried request only happens once. Send it as the Idempotency-Key header instead if you prefer; if you send both they must match. 8–200 characters. |
| `values` | map | Yes |  |

## Example request

```bash
curl https://app.getoatmilk.com/api/v1/contractor/hours.details.save \
  -H "Authorization: Bearer $OATMILK_OAUTH_TOKEN" \
  -H "X-Accounting-Organization: $OATMILK_ORGANIZATION_ID" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $(uuidgen)" \
  -d '{
  "hoursId": "1a2b3c4d-5e6f-4a7b-8c9d-0e1f2a3b4c5d",
  "values": {}
}'
```

Reference page: https://app.getoatmilk.com/docs/api/contractor/hours.details.save