# Developer API

The stable HTTP surface for inboxes, messages, search, and sending.

3 min read. HTML: https://sendwithflare.com/help/developer-api/

## What is public

Authenticate with `Authorization: Bearer fm_live_…`. The contract is OpenAPI 3.1 at `/openapi.json` on the API host.

- `GET` and `POST /api/v1/inboxes`
- `GET` and `PATCH /api/v1/messages` and `GET /api/v1/messages/:id`
- `GET /api/v1/search`
- `POST /api/v1/emails` for transactional send

The same scopes and mailbox limits as Agent Keys apply. A send that needs approval returns `202` with `status: approval_required` and does not send.