Mailgun Docs MCP Server

What is Mailgun Docs MCP Server?

Mailgun Docs MCP Server is a free, public MCP endpoint on Mailgun's documentation site that lets AI coding assistants search the Mailgun docs and read its OpenAPI definitions. It is read-only, needs no API key, and never sends email or touches your account.

Mailgun, part of Sinch, is an email API for sending, receiving, validating and tracking email. When you write a Mailgun integration with an assistant, the hard part is getting endpoint paths, parameters and regional base URLs right. This docs server answers those questions from Mailgun's own published specs, so the code your assistant writes is based on the current reference instead of memory.

How to use Mailgun Docs MCP Server?

The server is hosted on Mailgun's documentation site, so there is nothing to install and no credentials to configure:

https://documentation.mailgun.com/mcp

It speaks Streamable HTTP. Our probe connected anonymously and the server identified itself as "Docs MCP server".

Claude Code

claude mcp add --transport http mailgun-docs https://documentation.mailgun.com/mcp

Claude Desktop and claude.ai

Open Settings > Connectors, choose Add custom connector, name it "Mailgun Docs" and paste https://documentation.mailgun.com/mcp. There is no sign-in step.

Cursor

Add this to ~/.cursor/mcp.json:

{
  "mcpServers": {
    "mailgun-docs": {
      "url": "https://documentation.mailgun.com/mcp"
    }
  }
}

VS Code

Add this to .vscode/mcp.json in your workspace:

{
  "servers": {
    "mailgun-docs": {
      "type": "http",
      "url": "https://documentation.mailgun.com/mcp"
    }
  }
}

Key features of Mailgun Docs MCP Server

• Hosted on documentation.mailgun.com; free to use with no API key, account or OAuth.
• Read-only by design: the sandbox has no network access, so it cannot call the Mailgun API or send mail.
• Full-text search across Mailgun's documentation pages.
• Structured access to the published OpenAPI definitions: the Mailgun API, the Validations Service, the Email Preview API and Alerts.
• Endpoint lookups return parameters, examples, security requirements and the US (api.mailgun.net) and EU (api.eu.mailgun.net) server URLs.
• A "code mode" design: the assistant batches several lookups into one sandboxed script, which keeps round-trips and context use low.

Mailgun Docs MCP Server tools

Our probe returned two MCP tools, which together give access to a set of documentation functions:

• describe-tools returns the exact TypeScript signatures of the sandbox functions. The assistant calls it once before its first script so it never guesses parameter names.
• execute runs a JavaScript snippet in a sandbox whose only global is tools. There is no fetch, console or Node.js API; all lookups go through these functions:
  • listApis lists the API definitions published on the site.
  • getEndpoints lists every path and method for one API.
  • getEndpointInfo returns full detail for one endpoint, including parameters, examples and security.
  • getSecuritySchemes and getFullApiDescription return an API's auth schemes or its complete OpenAPI document.
  • search searches the documentation content.
  • submitFeedback reports a documentation page that is wrong or incomplete.

Use cases of Mailgun Docs MCP Server

• Writing send code: "Using the Mailgun docs, show me the endpoint and required fields to send a message with an attachment."
• Checking regions: "What base URL should I use for a domain hosted in Mailgun's EU region?"
• Email validation: "Find the Validations Service endpoint for validating a single address and list its parameters."
• Auth questions: "Which authentication scheme does the Mailgun API use?"
• Reviewing an existing integration against the current reference before an upgrade.

Mailgun Docs MCP Server vs alternatives

Mailgun also publishes the Mailgun MCP Server (@mailgun/mcp-server), which runs locally with your Mailgun API key and performs real account actions such as sending email, reading stats and managing domains. Mailgun's MCP page says that server is local only and not offered as a hosted service. The docs server on this page is the opposite: hosted, keyless and limited to documentation. Use the docs server while building, and the local server when you want the assistant to act on your account.

Troubleshooting Mailgun Docs MCP Server

• The assistant invents function names: ask it to call describe-tools first. The tool descriptions instruct the model never to guess signatures.
• A lookup returns a different API version than expected: several definitions share a title (for example the Validations Service). Results list the alternatives in otherMatches; pass the filePath from listApis to pick one.
• Requests to Mailgun fail inside a script: the sandbox cannot make network calls. Copy the generated code into your project and run it there with your own key.