Agent-native email, end to end.

Key → first send (your agent is created automatically) → first reply event. The five-minute path through the REST API, with copy-paste curl and fetch.

Bearer keys, the mk_live_ format, three scopes (send / read / manage), live vs test mode, and rotation. Everything about authenticating a request.

Workspace, agent, message, event, thread, draft, webhook, suppression, reputation — the eight nouns the API is built from, and how they fit together.

Every endpoint, with the exact request and response fields — messages, batch, received, events, webhooks, agents, keys, suppression.

One envelope on every failure — type, code, message, param, request_id. The type → status mapping and the full code list.

List events or tail the live SSE stream. Every event type, the inbound payload, and a reconnect-safe consumer.

Register an endpoint, verify the HMAC signature, handle retries. The push half of the events model, done safely.

The TypeScript SDK and the MCP server are on npm now; the Python SDK is coming next. All thin wrappers over the same REST surface.

Per-tier send caps, single-message payload limits, and the 429 + Retry-After behavior when you exceed them.