MCP server

Connect eusend to any AI coding tool over the Model Context Protocol — send email and manage domains, audiences, and broadcasts from Claude, Cursor, Codex, and other MCP clients.

The Model Context Protocol (MCP) lets AI tools call external services through a typed set of tools. eusend runs an MCP server so assistants like Claude Code, Claude Desktop, Cursor, and Codex can send email and manage domains, audiences, and broadcasts on your behalf — using your API key, through the exact same pipeline as the HTTP API. DKIM signing, tracking, suppression, rate limits, and your sending ceilings all apply identically.

ℹ

Using Claude Code? The eusend plugin installs this server and a skill that teaches Claude how eusend behaves — verified senders, idempotent retries, webhook signatures — in one command. The tools below let an assistant act on your account; the skill is what stops it writing the integration wrong.

There are two ways to connect, and they use the same tools underneath:

Remote (hosted)

Zero install — point your client at a URL. Best for getting started.

Local (stdio)

Runs on your machine via npx. Your key never leaves your computer.

How authentication works

Every tool call is authorized with one of your eusend API keys — the same key you use for the HTTP API. Nothing new to provision.

Remote: your client sends the key on each request as an Authorization: Bearer header. The hosted server holds no key of its own; it simply forwards authenticated calls to the API, so it can never do anything your key can't.
Local: the key is read from the EUSEND_API_KEY environment variable in your own MCP config and never leaves your machine.

Most tools need a full_access key. A sending_access key can only send, so listing domains, managing audiences and every other tool will return 403 FORBIDDEN — useful if you want an assistant that can send mail and nothing else.

ℹ

Use an eu_test_ key while wiring things up — calls are accepted and tracked but never delivered. Swap in an eu_live_ key to send for real.

Remote (hosted)

Endpoint: https://mcp.eusend.dev/mcp. No installation — add the URL to your client along with an Authorization header carrying your key.

Claude Code

shell

claude mcp add --transport http eusend https://mcp.eusend.dev/mcp \
  --header "Authorization: Bearer eu_live_xxxxxxxxxxxx"

Cursor, Windsurf, and other JSON-configured clients

Add a remote server entry to the client's MCP config (e.g. .cursor/mcp.json):

mcp.json

{
  "mcpServers": {
    "eusend": {
      "url": "https://mcp.eusend.dev/mcp",
      "headers": {
        "Authorization": "Bearer eu_live_xxxxxxxxxxxx"
      }
    }
  }
}

Codex

shell

codex mcp add eusend --url https://mcp.eusend.dev/mcp

Then set the Authorization: Bearer eu_live_… header for the eusend server in your Codex MCP configuration so tool calls are authenticated.

Local (stdio)

The local server runs as a subprocess your client launches on demand, via @eusend_dev/mcp. Your key stays in your own config and is never sent to eusend as part of setup. Requires Node.js.

Claude Code

shell

claude mcp add eusend \
  --env EUSEND_API_KEY=eu_live_xxxxxxxxxxxx \
  -- npx -y @eusend_dev/mcp

Claude Desktop, Cursor, and other JSON-configured clients

mcp.json

{
  "mcpServers": {
    "eusend": {
      "command": "npx",
      "args": ["-y", "@eusend_dev/mcp"],
      "env": {
        "EUSEND_API_KEY": "eu_live_xxxxxxxxxxxx",
        "EUSEND_FROM": "hello@yourdomain.com"
      }
    }
  }
}

ℹ

Setting EUSEND_FROM pins a default sender, so the assistant doesn't have to guess an address on every send. It must be on a verified domain.

Available tools

Parameter	Type	Description
`Emails`	`4 tools`	send_email, list_emails, get_email, cancel_email — send transactional mail and inspect delivery.
`Domains`	`4 tools`	list_domains, get_domain, create_domain, verify_domain — add a sending domain, read back its DNS records, and re-check them.
`Audiences & contacts`	`4 tools`	list_audiences, create_audience, list_contacts, create_contact — manage contact lists.
`Broadcasts`	`5 tools`	list_broadcasts, get_broadcast, create_broadcast, test_broadcast, send_broadcast — draft a broadcast, send yourself a test copy, then send it to an audience.
`Suppressions`	`2 tools`	list_suppressions, create_suppression — see which addresses are blocked and why, and stop sending to one.

⚠

Destructive actions — deleting domains, audiences, contacts, or API keys — are intentionally not exposed to the assistant. Broadcasts are also two steps: create_broadcast only drafts, and send_broadcast is a separate call, so a bulk send is never a single accidental action. test_broadcast sits between them and is the one an assistant should reach for first — it can only deliver to your own verified domains, so it cannot reach a list by mistake. Un-suppressing is absent for the same reason: suppressing stops mail, but removing an entry re-enables sending to an address that bounced or complained, and doing that in bulk is what wrecks a sender's reputation.

The sender address

Like every other way to send through eusend, the from address must use a domain you have verified. Sends from an unverified domain fail with DOMAIN_NOT_VERIFIED — see Domain Setup to add one. Pin a default with EUSEND_FROM (local) so the assistant always has a valid sender to use.

Remote (hosted)

Local (stdio)

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