FZ-013 · EMAIL

Owlpost

Email API for apps and AI agents, with its own inboxes.

Live LAUNCH FZ stackEmail
Visit owlpost.to Launched: 2026-09-29
Status
Live
Pipeline stage
LAUNCH
Sector
EMAIL
Autonomy target
LEVEL 4 · SELF-OPTIMIZING
Built with
3 live · 2 planned

The problem

Apps send email through one service and parse replies with another, while AI agents have no inbox.

What it does

Owlpost is designed as one email API that sends mail, receives replies as JSON and gives each agent an address.

How it works

  1. Transactional and marketing email from one SDK, with a timeline for every message
  2. Inbound email parsed to JSON and posted to your webhook
  3. Real inboxes for AI agents, created with one API call

The free tier is 3,000 emails a month (100 a day) with 3 agent inboxes. Paid plans are listed on the site from $12 a month.

Stop stitching a sending service, an inbound parser and a mailbox together.

TodaySending runs in the cloud Email Sending; sign-up is by early access.

The film

Email for apps and agents.

Aims

Autonomous operation
Sending runs itself: a message is accepted, split, signed, delivered and watched, and bounces and complaints feed the suppression list with no one in the loop. People set limits and look at the dashboard; they do not push mail through by hand.
Intelligence
Mostly plain code. Models help at the edges: an AI panel that edits a template and shows every change as a diff to accept or reject, and screening that holds a suspicious inbound message before an agent reads it.
Growth
Developer-led, and first inside Factory Zero: Owlpost replaces Resend in the ventures that send mail today. Growth is emails sent and agent inboxes in use by teams outside Factory Zero, counted from the first of those.
The technical detail

An email API for apps and AI agents. One key sends transactional and marketing email, receives inbound mail as JSON by webhook, and creates persistent inboxes for agents on owlpost.to or your own domain. Deliverability is part of the path: separate transactional and marketing streams, DKIM, SPF and DMARC records set up for you, a suppression list checked before every send, one-click unsubscribe. It is built in Rust on the Cratefield harness and managed edge infrastructure. What exists today is the site, the API at api.owlpost.to, inbound mail into inboxes and sending through Cloudflare Email Sending; the SDKs are still being built. Its first job was to replace Resend inside Factory Zero.