Horizon Mail. Programmable email for AI agents.

Programmable email for AI agents.

Hosted, secure mailboxes built for agents that need a real inbox. LLM triage, classification, spam protection, and agent-native auth via auth.md, out of the box.

● First 50 free forever ● Manual approval ● No credit card

Your agents register themselves.

Drop auth.md at our domain. Your agent reads it, provisions a mailbox, and starts sending. No sign-up form. No human in the loop.

auth.md flow

One file. Three steps. Zero forms.

Uses auth.md from WorkOS. Your agent fetches our spec, provisions an anonymous mailbox, and works immediately. The user claims it later if they want.

Discovery. Agent reads /auth.md.
Provision. Anonymous mailbox plus scoped API key.
Claim. Bind to a user account when convenient.

GET /auth.md →curl /install.sh | bash →

no human in the loop — your agent reads the spec, provisions itself, and starts sending

# Install the CLI, then provision a mailbox.
curl -fsSL https://mail.myhorizon.co.za/install.sh | bash

# Step 1. Provision a mailbox (no auth)
hmail provision demo-agent
# → { clientId, apiKey, claimToken, mailboxAddress }

# Step 2. Use the credential immediately
curl https://billing.myhorizon.co.za/api/messages \
  -H "Authorization: Bearer $apiKey"

# Step 3. Optional: send user to claim
https://app.myhorizon.co.za/claim?nonce=...

Email that speaks JSON, not SMTP.

Every primitive you'd expect from a modern API, surfaced cleanly over HTTP, with the deliverability of a real MTA underneath.

LLM

Triage & classification

Every inbound message is auto-classified into intent buckets: support, billing, urgent, spam, ignore. Route each bucket to its own webhook or action.

SECURE

Hardened spam protection

Stalwart engine plus an LLM second pass, sender reputation scoring, and per-mailbox rate-limits. Your agents see only the mail that matters.

OPS

Production-grade infra

SealedSecrets, network isolation, full audit logs, DKIM + SPF aligned by default. Built on the same infra Bermont runs in production.

WEBHOOKS

Webhooks first

Inbound mail arrives as structured JSON at your endpoint. Per-mailbox secrets, retries, and replay built in.

KEYS

Scoped API keys

Each agent gets its own signed, scoped, expirable, revocable key. inbound:read, outbound:send, mailbox:admin.

DNS

BYO domain (Pro)

Bring your own domain. We wire up Cloudflare Email Routing, DKIM, and tunnel ingress. Or stay on *.mail.myhorizon.co.za for free.

One paid tier. Honest limits.

Indie pricing for indie builders and small teams. No enterprise haze, no per-seat math, no contact-sales gate.

Free beta

$0R0 / mo

First 50 only · manual approval · no credit card

1 mailbox on *.mail.myhorizon.co.za
Unlimited mail with your verified personal email
100 inbound / mo · 10 outbound / day non-personal · 50 / mo
Webhooks + API receive
Per-mailbox API key
Basic spam filter
BYO domain
LLM triage

Request access →

Pro

$5.99R99 / mo

or $59/yrR999/yr, two months free

5 mailboxes
10,000 inbound · 1,000 outbound / month
BYO domain with CF Email Routing + DKIM + tunnel
LLM triage & classification
Webhooks + replay + audit log
Scoped API keys with revoke + audit
Email rules in code
Priority support

Join the waitlist →

Need more volume or a dedicated deploy in your own cluster? Talk to Luke.