Cloudflare Email Service

Your knowledge of the Cloudflare Email Service, Email Routing or Email Sending may be outdated. Prefer retrieval over pre-training for any Cloudflare Email Service task.

Cloudflare Email Service lets you send transactional emails and route incoming emails, all within the Cloudflare platform. Your knowledge of this product may be outdated — it launched in 2025 and is evolving rapidly. Prefer retrieval over pre-training for any Email Service task.

If there is any discrepancy between this skill and the sources below, always trust the original source. The Cloudflare docs, REST API spec, @cloudflare/workers-types, and Agents SDK repo are the source of truth. This skill is a convenience guide — it may lag behind the latest changes. When in doubt, retrieve from the sources below and use what they say.

Retrieval Sources

Source	How to retrieve	Use for
Cloudflare docs	Cloudflare MCP `docs` tool or URL `https://developers.cloudflare.com/email-service/`	API reference, limits, pricing, latest features
REST API spec	`https://developers.cloudflare.com/api/resources/email_sending`	OpenAPI spec for the Email Sending REST API
Workers types	`https://www.npmjs.com/package/@cloudflare/workers-types`	Type signatures, binding shapes
Agents SDK docs	Fetch `docs/email.md` from `https://github.com/cloudflare/agents/tree/main/docs`	Email handling in Agents SDK

FIRST: Check Prerequisites

Before writing any email code, verify the basics are in place:

Domain onboarded? Run npx wrangler email sending list to see which domains have email sending enabled. If the domain isn't listed, run npx wrangler email sending enable userdomain.com or see cli-and-mcp.md for full setup instructions.
Binding configured? Look for send_email in wrangler.jsonc (for Workers)
postal-mime installed? Run npm ls postal-mime (only needed for receiving/parsing emails)

What Do You Need?

Start here. Find your situation, then follow the link for full details.

I want to...	Path	Reference
Send emails from a Cloudflare Worker	Workers binding (no API keys needed)	sending.md
Send emails from an AI agent built with [Cloudflare Agents SDK](https://developers.cloudflare.com/agents/)	`onEmail()` + `replyToEmail()` in Agent class	sending.md
Send emails from an external app or agent (Node.js, Go, Python, etc.)	REST API with Bearer token	rest-api.md
Send emails from a coding agent (Claude Code, Cursor, Copilot, etc.)	MCP tools, wrangler CLI, or REST API	cli-and-mcp.md
Receive and process incoming emails (Email Routing)	Workers `email()` handler	routing.md
Set up Email Sending or Email Routing	`wrangler email sending enable`

Quick Start — Workers Binding

Add the binding to wrangler.jsonc, then call env.EMAIL.send(). The from domain must be onboarded via npx wrangler email sending enable yourdomain.com.

// wrangler.jsonc
{ "send_email": [{ "name": "EMAIL" }] }

const response = await env.EMAIL.send({
  to: "user@example.com",
  from: { email: "welcome@yourdomain.com", name: "My App" },
  subject: "Welcome!",
  html: "<h1>Welcome!</h1>",
  text: "Welcome!",
});

The binding is recommended for Workers — no API keys needed. If a user specifically requests the REST API from within a Worker (e.g., they already have an API token workflow), that works too — see rest-api.md.

See sending.md for the full API, batch sends, attachments, custom headers, restricted bindings, and Agents SDK integration.

Quick Start — REST API

For apps outside Workers, or within Workers if the user explicitly requests it. Key differences from the Workers binding:

Endpoint: POST https://api.cloudflare.com/client/v4/accounts/{account_id}/email/sending/send
from object uses address (not email): { "address": "...", "name": "..." }
replyTo is reply_to (snake_case)
Response returns { delivered: [], permanent_bounces: [], queued: [] } (not messageId)

See rest-api.md for curl examples, response format, and error handling.

Common Mistakes

Mistake	Why It Happens	Fix
Forgetting `send_email` binding in wrangler config	Email Service uses a binding, not an API key	Add `"send_email": [{ "name": "EMAIL" }]` to wrangler.jsonc
Sending from an unverified domain	Domain must be onboarded onto Email Sending before first send	Run `wrangler email sending enable yourdomain.com` or onboard in Dashboard
Reading `message.raw` twice in email handler	The raw stream is single-use — second read returns empty	Buffer first: `const raw = await new Response(message.raw).arrayBuffer()`
Missing `text` field (HTML only)	Some email clients only show plain text; also helps spam scores	Always include both `html` and `text` versions
Using email for marketing/bulk sends

References

Read the reference that matches your situation. You don't need all of them.

[references/sending.md](references/sending.md) — Workers binding API, attachments, Agents SDK email. For Workers or Agents SDK.
[references/rest-api.md](references/rest-api.md) — REST endpoint, curl examples, error handling. For apps NOT on Workers.
[references/routing.md](references/routing.md) — Inbound email() handler, forwarding, replying, parsing. For receiving emails.
[references/cli-and-mcp.md](references/cli-and-mcp.md) — Domain setup, wrangler commands, MCP tools. For first-time setup.
[references/deliverability.md](references/deliverability.md) — SPF/DKIM/DMARC, bounces, suppressions, best practices.

Skill name	cloudflare-email-service
Trigger conditions	Send and receive transactional emails with Cloudflare Email Service (Email Sending + Email Routing). Use when building email sending (Workers binding or REST API), email routing, Agents SDK email handling, or integrating email into any app — Workers, Node.js, Python, Go, etc. Also use for email deliverability, SPF/DKIM/DMARC, wrangler email setup, MCP email tools, or when a coding agent needs to send emails. Even for simple requests like "add email to my Worker" — this skill has critical config details.

Cloudflare Email Service

Skill specification

Install cloudflare-email-service

Claude Code

Codex

Cursor

Gemini CLI

SKILL.md