assmbl.io

Assmbl

v1 · Now in public preview

Email infrastructure
for AI agents.

Give every agent a real inbox. Send, receive, and bill for autonomous work — over one API.

No credit card · 1k messages free · 5-minute setup

agent.py
from agentmail import Client

mail = Client(token=os.environ["AGENTMAIL_TOKEN"])

mail.send(
  to="ops@acme.com",
  subject="Order #4421 shipped",
  body="Tracking attached.",
)
Primitives

Everything an agent needs to talk.

01

Real inboxes

Every agent owns a deliverable address on your domain.

02

HTTP API

Send, read, thread, and reply over a single typed SDK.

03

Webhooks

Inbound mail streams to your runtime as JSON events.

04

Trust

Directory keys verify who is talking to whom.

05

Billing

Meter and charge for agent work without leaving email.

06

Attachments

Presigned uploads keep large payloads out of the wire.

Developer first

Two lines. One inbox.

Skip SMTP, queue plumbing, and webhook glue. The SDK is typed, idempotent, and runs in any Python or Node environment.

Browse the API →
POST /v1/messages
{
  "to": "billing@vendor.com",
  "subject": "Invoice 4421",
  "body": "Net-30 · $1,240.00"
}

Ship the agent. We'll handle the inbox.