Primitive developer resources

Everything you need to build on primitive.dev, the email API for AI agents. Each resource lives at a predictable URL so an agent can find it by name.

Primitive API documentation

Guides and reference for the Primitive v1 REST API — sending, receiving, managed inboxes, domains, and Functions.

Primitive OpenAPI specification

The complete OpenAPI 3.1 description of the Primitive REST API. Point any code generator or agent at it.

Primitive authentication guide

How agents get a credential — the credential-free demo, agent signup flow, and Bearer token auth for the API and MCP.

Primitive webhooks and inbound handlers

Receive events for inbound mail, or run a hosted JavaScript handler on every received message with Functions.

Primitive MCP server

A hosted Model Context Protocol server so agents can discover and call the full surface — with a credential-free demo tool to try first.

Primitive SDKs and CLI

Node, Python, and Go SDKs plus the primitive CLI, all generated from the same OpenAPI spec and public on GitHub.

Primitive machine-readable surfaces

Orientation and discovery files for LLMs and agents probing the domain by name.

Try it with no account

The Primitive API is discoverable and dry-runnable without credentials. List every operation, then run one real call against the demo endpoint:

curl https://api.primitive.dev/v1/openapi
curl -X POST https://api.primitive.dev/v1/send-mail/demo \
  -H 'Content-Type: application/json' \
  -d '{"from":"agent@your-subdomain.primitive.email","to":"someone@example.com","subject":"Hello","body_text":"Testing the Primitive send flow."}'

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