Cloudflare Email Service

From the author

Implement or troubleshoot Cloudflare Email Sending and Email Routing integrations and their delivery configuration.

— the description by Cloudflare

AutoGineer summary

Written by AutoGineer from the skill’s own files, not by the author

The Cloudflare Email Service skill provides a framework for implementing transactional email sending and inbound email routing within the Cloudflare ecosystem. It covers domain onboarding, configuration of Workers bindings, REST API usage, and best practices for maintaining high deliverability. The skill emphasizes using retrieval-based methods to ensure developers access the most current API specifications and platform limits, as the service is rapidly evolving.

What it does

Enables transactional email sending via Cloudflare Workers or REST API.
Configures inbound email routing and processing using Workers handlers.
Provides commands for domain onboarding and DNS record management.
Offers guidance on deliverability, including SPF, DKIM, and DMARC configuration.
Supports integration with Cloudflare Agents SDK for automated email workflows.
Facilitates monitoring of sending limits, bounce handling, and suppression lists.

When to use it

When you need to send transactional emails from a Cloudflare Worker or external application.
When you need to receive and process incoming emails programmatically.
When setting up a new domain for email services on the Cloudflare platform.
When troubleshooting email delivery issues or managing suppression lists.
When integrating email capabilities into an AI agent built with the Cloudflare Agents SDK.

Advantages

Native integration with Cloudflare Workers and infrastructure.
Automatic handling of SPF, DKIM, and bounce management.
Unified platform for both sending and routing email.
Direct access to analytics and delivery feedback via API.
Supports both programmatic (API/Worker) and CLI-based management.

Usage examples

“How do I enable email sending for my domain example.com using the CLI?”: The agent will provide the command 'npx wrangler email sending enable example.com' and explain how to verify DNS records.
“Show me how to send a transactional email from a Cloudflare Worker.”: The agent will guide you to configure the 'send_email' binding in wrangler.jsonc and use the appropriate Worker binding syntax.
“How can I check my daily email sending quota?”: The agent will provide the REST API endpoint for the limits resource and explain how to authenticate using your API token.
“What is the best way to handle incoming emails in a Worker?”: The agent will explain the use of the email() handler and provide a pattern for parsing raw email content.

Install

Download the skill as a ZIP:
https://autogineer.com/agent-skills/cloudflare/cloudflare-email-service/download

Unzip it into the cross-client skills folder of your project:

mkdir -p .agents/skills && unzip cloudflare-email-service.zip -d .agents/skills

Documentation by Cloudflare

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/index.md`	API reference, limits, pricing, latest features
REST API spec	`https://developers.cloudflare.com/api/resources/email_sending/index.md`	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	Email agent walkthrough	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	`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` / `wrangler email routing enable`, or Dashboard	cli-and-mcp.md
Improve deliverability, avoid spam folders	Authentication, content, compliance	deliverability.md

Sending Workflow

Prefer the binding for Workers; use REST for external apps or when explicitly requested. Read sending.md or rest-api.md to retrieve the documentation for the selected task before writing code. These guides cover setup, recipients, attachments, headers, limits, response handling, and errors; the Workers guide also covers Agents SDK integration and types matched to the project configuration.

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	Email Service is for transactional email only	Use a dedicated marketing email platform for newsletters and campaigns
Forwarding to unverified destinations	`message.forward()` only works with verified addresses	Run `wrangler email routing addresses create [email protected]` or add in Dashboard
Testing with fake addresses	Bounces from non-existent addresses hurt sender reputation	Use real addresses you control during development
Hardcoding API tokens in source code	Tokens in code get committed and leaked	Use environment variables or Cloudflare secrets
Ignoring the `from` domain requirement	The `from` address must use a domain onboarded to Email Service	Verify the domain first, then send from `[email protected]`
Using `email` key in REST API `from` object	REST API uses `address` not `email` for `from` object	Use `{ "address": "...", "name": "..." }` for REST, `{ "email": "...", "name": "..." }` for Workers
Using `replyTo` in REST API	REST API uses snake_case field names	Use `reply_to` for REST API, `replyTo` for Workers binding

References

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

references/sending.md — Documentation map for Workers binding, attachments, and Agents SDK email.
references/rest-api.md — Documentation map for HTTP sending, request schemas, responses, and errors.
references/routing.md — Inbound email() handler, forwarding, replying, parsing. For receiving emails.
references/cli-and-mcp.md — Domain setup, wrangler commands, MCP tools. For first-time setup.
references/deliverability.md — SPF/DKIM/DMARC, bounces, suppressions, best practices.

Skill feedback

If the user reports that this skill gave incorrect or outdated guidance, or is missing information, read references/skill-feedback.md.

Files

ATTRIBUTION.mdAdded by AutoGineer884 B
LICENSELicence file added by AutoGineer11.1 KiB
SKILL.md6.6 KiB
references/cli-and-mcp.md4.0 KiB
references/deliverability.md8.8 KiB
references/rest-api.md1.8 KiB
references/routing.md7.3 KiB
references/sending.md2.6 KiB
references/skill-feedback.md2.8 KiB

Requirements and compatibility

Works with: Claude Code, Claude apps, OpenAI Codex, GitHub Copilot, Cursor, Gemini CLI, Kiro, OpenCode, Goose, Amp, Roo Code, JetBrains Junie, Factory Droid, Devin (ex-Windsurf), Mistral Vibe, OpenHands, Letta

“Works with” means the tool reads the open Agent Skills format; a skill written for one tool may use features others lack.

Needs: Needs an API key, Needs Node.js

Security

No issues found by our static scan· No issues found

A static scan is not a guarantee. Skills are third-party content: review a skill before you let an agent use it.

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Download ZIP

The ZIP holds the skill’s files, its licence files and an ATTRIBUTION.md. Download cloudflare-email-service.zip