resend-email-mcp
The most complete Resend MCP server — full coverage of the Resend API (emails, domains, contacts, broadcasts, templates, segments, topics, webhooks, logs) plus a unique debug/diagnostics layer no other Resend MCP offers: deliverability analysis, DNS troubleshooting, email lifecycle inspection, bounce explanation, and account auditing.
Works with Claude Code, Cursor, Claude Desktop, and any other MCP client.
Why this MCP
| resend-email-mcp | Official resend-mcp | Minimal MCPs |
|---|
| Send / batch / schedule | ✅ | ✅ | partial |
| Domains, contacts, broadcasts, templates, segments, topics, webhooks | ✅ | ✅ | ❌ |
| API request logs tools | ✅ | ❌ | ❌ |
| Debug layer (diagnose, analyze, inspect, explain, audit) | ✅ 7 tools | ❌ | ❌ |
| Readonly safety mode | ✅ | ❌ | ❌ |
| Raw escape hatch for new endpoints | ✅ | ❌ | ❌ |
| Idempotency-key support | ✅ | partial | ❌ |
75 tools + 2 resources.
Quick start
1. Get a Resend API key
Create one at https://resend.com/api-keys.
2. Add to your MCP client
Claude Code (CLI)
claude mcp add resend -e RESEND_API_KEY=re_xxxxxxxx -- npx -y resend-email-mcp
Cursor / Claude Desktop / generic (mcp.json / claude_desktop_config.json)
{
"mcpServers": {
"resend": {
"command": "npx",
"args": ["-y", "resend-email-mcp"],
"env": {
"RESEND_API_KEY": "re_xxxxxxxx",
"RESEND_FROM": "Acme <hello@acme.com>"
}
}
}
}
Config file locations:
- Claude Desktop (Windows):
%APPDATA%\Claude\claude_desktop_config.json
- Claude Desktop (macOS):
~/Library/Application Support/Claude/claude_desktop_config.json
- Cursor:
~/.cursor/mcp.json (or per-project .cursor/mcp.json)
Restart the client and ask: "Send a test email to delivered@resend.dev" or "Audit my Resend account."
Configuration
| Env var | Required | Description |
|---|
RESEND_API_KEY | ✅ | Your Resend API key |
RESEND_FROM | – | Default sender for send_email when from is omitted (must be a verified domain) |
RESEND_REPLY_TO | – | Default Reply-To address |
RESEND_READONLY | – | true blocks every mutating tool (send/create/update/delete). Safe exploration of production |
RESEND_ATTACHMENTS_DIR | – | Directory that send_email's localPath attachments are restricted to. Unset = disk reads disabled (safe default; path traversal is blocked) |
RESEND_BASE_URL | – | Override API base URL (default https://api.resend.com). Must be https (http only for localhost) |
RESEND_MAX_RETRIES | – | Retries on 429/5xx (default 3) |
Tools
Emails
send_email · send_batch_emails · get_email · list_emails · update_email · cancel_email · preview_email
send_email accepts attachments by base64 content, public path (URL), or localPath (a file on disk, read and base64-encoded automatically — only enabled when RESEND_ATTACHMENTS_DIR is set, and restricted to that directory). preview_email dry-runs a message — resolving the final sender, sizing attachments, and surfacing warnings — without sending.
Attachments (sent & received)
list_email_attachments · get_email_attachment · list_received_emails · get_received_email · list_received_attachments · get_received_attachment
Domains
create_domain · get_domain · list_domains · update_domain · delete_domain · verify_domain
API keys
create_api_key · list_api_keys · delete_api_key
Broadcasts
create_broadcast · get_broadcast · list_broadcasts · update_broadcast · send_broadcast · delete_broadcast
Contacts
create_contact · get_contact · list_contacts · update_contact · delete_contact · get_contact_topics · update_contact_topics · list_contact_segments · add_contact_to_segment · remove_contact_from_segment
Contact properties
create_contact_property · get_contact_property · list_contact_properties · update_contact_property · delete_contact_property
Segments
create_segment · get_segment · list_segments · delete_segment · list_segment_contacts
Templates
create_template · get_template · list_templates · update_template · delete_template · publish_template · duplicate_template
Topics
create_topic · get_topic · list_topics · update_topic · delete_topic
Webhooks
create_webhook · get_webhook · list_webhooks · update_webhook · delete_webhook
Logs
list_logs · get_log
🔍 Debug & diagnostics (the differentiator)
| Tool | What it does |
|---|
diagnose_domain | Inspects every DNS record (SPF/DKIM/DMARC) and reports what's missing + how to fix it |
analyze_deliverability | Aggregates recent sends into delivery/bounce/complaint rates with a health verdict |
inspect_email | Renders one email's full lifecycle timeline and flags problems |
explain_bounce | Classifies a bounce (hard/soft/block) and recommends the action |
audit_account | One-shot health check of domains, keys, and deliverability |
search_logs | Smart filtering of API logs by status/path/recipient to find failures |
test_send | Safely simulates delivered/bounced/complained via Resend sandbox addresses |
Escape hatch
resend_raw — call any Resend endpoint not yet wrapped in a dedicated tool.
Resources
Beyond tools, the server exposes two read-only MCP resources so a client can pull account context without spending a tool call:
| URI | Content |
|---|
resend://account | Domains + API keys snapshot |
resend://domains | All sending domains with verification status |
Every tool is annotated with MCP hints (readOnlyHint, destructiveHint, idempotentHint) so clients can show which operations are safe and which need confirmation.
Example prompts
- "Diagnose why acme.com isn't verified." →
diagnose_domain
- "How healthy is my email sending this week?" →
analyze_deliverability
- "What happened to email re_abc123?" →
inspect_email
- "Why did that email bounce and what should I do?" →
explain_bounce
- "Something's wrong with my Resend setup — check everything." →
audit_account
- "Send our launch newsletter to the 'beta' segment." →
create_broadcast + send_broadcast
Testing safely
Use Resend's sandbox addresses (no reputation impact):
delivered@resend.dev — simulates deliverybounced@resend.dev — simulates a hard bouncecomplained@resend.dev — simulates a spam complaint
Or just run test_send and then inspect_email on the returned ID.
Enable RESEND_READONLY=true to explore a production account without any risk of sending or deleting.
Troubleshooting
This MCP is built to debug itself — when something fails, reach for the diagnostic tools instead of guessing.
| Symptom / error | Likely cause | What to run |
|---|
validation_error: from domain is not verified | Your from/RESEND_FROM domain isn't verified | list_domains → diagnose_domain (shows missing DNS records + fixes) → verify_domain |
| Emails send but never arrive | Deliverability / reputation issue | analyze_deliverability then inspect_email on a sample ID |
missing_api_key / invalid_api_key (HTTP 401) | RESEND_API_KEY unset or wrong | Check the .env; create a key at resend.com/api-keys |
restricted_api_key / not_authorized (403) | Key scoped to sending-only or one domain | Use a full_access key (list_api_keys to inspect) |
rate_limit_exceeded (429) | Too many requests | The client auto-retries with backoff; reduce volume |
daily_quota_exceeded | Plan send limit reached | Upgrade plan or wait for reset |
| A specific email bounced | Invalid/blocking recipient | explain_bounce (classifies hard/soft/block + action) |
| "Is anything wrong with my setup?" | — | audit_account (one-shot health check) |
| Request fails for unknown reason | — | search_logs with only_errors: true |
Every error returned by this server includes the HTTP status, Resend's error name, and an actionable Hint line.
Local development
git clone https://github.com/helbertparanhos/resend-email-mcp.git
cd resend-email-mcp
npm install
npm run build
cp .env.example .env # add your RESEND_API_KEY
npm run inspector # opens the MCP Inspector against the built server
License
MIT © Helbert Paranhos / Strat Academy
Built with the Model Context Protocol. Not affiliated with Resend.
