primitive
app

About Primitive

What we build

Primitive is email infrastructure for AI agents. Two primitives: a one-line primitive chat <email> <message> verb that sends a message and waits for the threaded reply, and a managed *.primitive.email subdomain that runs a JavaScript handler on every inbound message. Together they let an agent reach any other agent or person over email, and let you expose an agent that other agents can reach without standing up your own MX.

We handle the protocol surface so agents do not have to: inbound MX, SPF, DKIM, DMARC, TLS-RPT, bounce processing, and IP reputation. No SMTP credentials in an agent context, no API key copy-paste from a dashboard, no DNS to configure for the managed path.

Why email

Email is the universal addressing scheme. Every business, every support team, every developer relations function already runs on it. When an agent needs to reach someone or something outside its own ecosystem, email is the lowest-friction protocol that already works. We think the agent-native version of that protocol should be a one-line verb, not a vendor integration.

Company

primitive.dev is based in San Francisco and is backed by Y Combinator.

Team

We are a small founding team of infrastructure engineers based in San Francisco. Our backgrounds span email delivery systems, developer tooling, distributed systems, and agentic AI. We started Primitive because every agent integration we built eventually needed email — and none of the existing infrastructure was designed for the two-way, agent-native use case.

  • Ethan Byrd — CEO and Founder
  • Abi Guillen — Chief of Staff

The team owns the full stack: the inbound MX fleet, the outbound delivery pipeline, the hosted Functions runtime, the REST API, the SDKs and CLI, and this web application. The inbound MX implementation and the SDKs are public on GitHub.

Open code

Our inbound MX implementation, SDKs (Node, Python, Go), and CLI are public on github.com/primitivedotdev. Skills for popular coding agents ship on skills.sh under primitivedotdev/skills.

Get in touch

The fastest answer about the product itself is to run primitive chat dev_help@agent.primitive.dev "<question>". That reaches our hosted dev_help agent, grounded in the public docs. For everything else see the contact page.