Appendix

What Appendix MCP server does

The Appendix MCP server connects an AI agent to Appendix's medical API. It supports two parts of a health workflow: finding information in medical literature and treatment guidelines, and sending a clinical encounter summary for review by a physician.

An agent can search the available knowledge base, inspect the conditions and medications supported by the service, and submit a clinical letter. The README states that reviewed encounters can produce clinical guidance and prescriptions from board-certified physicians. The service is intended for health conversations that need a physician-reviewed opinion.

How it works

The Appendix MCP server uses Streamable HTTP rather than stdio. MCP requests are sent to https://mcp.appendix.com/mcp, and the server operates in stateless mode at the /mcp endpoint. A health probe is available at /health for hosting-platform checks.

A typical agent workflow can begin with search_knowledge_base to find relevant medical literature or treatment guidelines. It can call list_conditions to see available conditions and medications, then use submit_encounter to send a clinical letter for physician review. The available material does not define the request fields or response schemas for these tools.

Setup and configuration

For Claude Code, register the remote server with:

claude mcp add --transport http appendix https://mcp.appendix.com/mcp

Claude Desktop and Claude.ai custom connectors use the same URL in the MCP server configuration:

{
  "mcpServers": {
    "appendix": {
      "url": "https://mcp.appendix.com/mcp"
    }
  }
}

The Appendix MCP server can also be supplied through the Anthropic Messages API's mcp_servers configuration. The documented API base URL is https://api.appendix.com, controlled by API_BASE_URL. Self-hosted development uses npm install, npm run build, and npm start; npm run dev starts watch mode. PORT sets the HTTP listener port and defaults to 3001.

Tools and capabilities

The server exposes three MCP tools:

• search_knowledge_base: searches medical literature and treatment guidelines.
• submit_encounter: submits a clinical letter for physician review.
• list_conditions: lists available conditions and medications.

Together, these tools let an agent research a health question, check the service's supported catalog, and request review of a clinical encounter. The Appendix MCP server does not document additional tools in the provided material.

Limitations and notes

The documented transport is Streamable HTTP only, using the current MCP specification identified in the README as 2025-03-26. This is a remote HTTP service, not a local stdio server. The README does not specify tool schemas, authentication steps, turnaround times, supported countries, prescription eligibility rules, or the clinical situations accepted for review. Confirm those details with Appendix before building a production workflow.

The server's documented endpoints are GET /health and POST, GET, and DELETE /mcp. The local development server uses the configured port, while the hosted MCP URL is provided by Appendix.