Docs · Developers
API & webhooks
In short: Flap send API and inbound webhooks for Solo and above. Create keys in Settings → Developers.
Solo and above include API keys and inbound webhooks. Create keys and hooks in Settings → Developers, then call the HTTPS API at useflap.online.
POST /api/v1/send
Authorize with Authorization: Bearer flap_…. Body fields: to, subject, text, html, from, cc, bcc. Success: { "ok": true, "id": "msg_…" }
- API keys are created in Settings → Developers. The full token is shown once.
- Keys are available on Solo (5), Builder (25), and Studio (100).
- Sends count toward your plan’s monthly outbound quota and storage limits.
- From addresses must belong to a mailbox on your workspace.
Inbound webhooks
Compute SHA-256 hex of `${secret}.${rawBody}` and compare to x-flap-signature. Use the secret shown once when you create the webhook.
- mail.received: Fired after inbound mail is stored for your workspace.
- Content-Type: application/json
- x-flap-event: Event name, e.g. mail.received
- x-flap-signature: Hex SHA-256 of secret + '.' + raw body
- Webhook URL must be https://
- Subscribe to mail.received or * (all events).
- Delivery attempts are logged in Settings → Developers → Deliveries (last 20).
- Webhook slots follow plan limits (Solo 3, Builder 15, Studio 50).
- Plan limits — Solo 5 keys / 3 webhooks; Builder 25/15; Studio 100/50.