On April 16, 2026, Cloudflare open-sourced Agentic Inbox, a self-hosted email client with a built-in AI agent that runs on Workers. It simultaneously moved Email Sending to public beta, letting developers handle two-way email natively from Workers and the Agents SDK.
April 16, 2026 · Cloudflare
Agentic Inbox: An AI Email Client Running Entirely on the Edge
Cloudflare's open-source, self-hosted email client pairs a built-in AI agent with the newly beta Email Service — handling reception, sending, and AI-drafted replies using only Cloudflare Workers.
9
email tools for the AI agent — read, search, draft, send & more
100%
built from Cloudflare services — no external infrastructure
Apache 2.0
open license — anyone can study or fork the reference app
How a message flows through the inbox
1 · RECEIVE
Mail arrives via Email Routing catch-all
→
2 · TRIGGER
Agents SDK hook fires on the new message
→
3 · DRAFT
Workers AI auto-generates a reply draft
→
4 · CONFIRM
Sending always needs explicit confirmation
Under the hood — one isolated mailbox per Durable Object
Each mailbox runs as its own Durable Object (SQLite + R2), with attachments in R2 and an embedded MCP server at /mcp for external tools like Claude Code.
Frontend
React 19 · React Router v7 · Tailwind · TipTap
Backend
Hono · Workers · Durable Objects + SQLite · R2
AI Agent
Agents SDK · Workers AI (kimi-k2.5) · AI SDK v6
Auth
Cloudflare Access (JWT)
Seen as strengths
Data sovereignty from full self-hosting
Low-cost serverless operation
Clean reference to study and fork
Noted concerns
One Access policy can grant all mailboxes, incl. via MCP
Token errors during Access setup can trip users up
Reads as an experiment, not a daily-use tool
Continue reading The rest of this article is for AI News Blitz readers. Choose an option below to keep reading.
Already purchased? Sign in ✓ Signed in — this article isn’t included in your current plan.Unlocking the full article…