US Federal Regulations (CFR) MCP MCP server

This MCP server allows AI agents to query the Electronic Code of Federal Regulations and the Federal Register. It enables users to retrieve specific regulatory text, such as 'what does 21 CFR 11.10 say?', and find FDA proposals on topics like food dyes. The server provides general information for research purposes and explicitly states it does not constitute legal advice.

Endpoint and access

No sign-in: your client connects and lists tools immediately, with no account or key.

No sign-inEndpoint checked 2026-10-05Operated by OpenKrill

MCP endpoint (Streamable HTTP)

https://rules.openkrill.app/mcp

Vendor documentation

What you can do with it

Retrieve specific text from US Federal Regulations (CFR)
Find FDA proposals on specific topics like food dyes
Research federal regulatory history via the Federal Register

Tools advertised by the last live check:

get_cfr_section
search_cfr
search_federal_register
submit_feedback
get_feedback_reply
index_tools

Connect from your client

Each snippet registers the same endpoint; pick the client you use.

This server is operated by the named third party. Listing and endpoint checks are not an endorsement or a security audit. Review the operator's permissions, terms, and data handling before connecting. How listings are checked and corrected.

Claude Code

Run this once in a terminal. It registers a Streamable HTTP server. Use --scope project to write .mcp.json for the repo.

Claude Code configuration

claude mcp add --transport http us-federal-regulations-cfr-mcp https://rules.openkrill.app/mcp

Codex

Run this once. Codex stores MCP servers in ~/.codex/config.toml (or .codex/config.toml in a trusted project).

Codex configuration

codex mcp add us-federal-regulations-cfr-mcp --url https://rules.openkrill.app/mcp

Cursor

Merge this server into .cursor/mcp.json in your project, then enable us-federal-regulations-cfr-mcp in your MCP settings.

Cursor configuration

{
  "mcpServers": {
    "us-federal-regulations-cfr-mcp": {
      "url": "https://rules.openkrill.app/mcp"
    }
  }
}

Cline

Merge this into cline_mcp_settings.json (Cline → MCP Servers → Configure). The type must be streamableHttp for a remote HTTP server.

Cline configuration

{
  "mcpServers": {
    "us-federal-regulations-cfr-mcp": {
      "type": "streamableHttp",
      "url": "https://rules.openkrill.app/mcp",
      "disabled": false
    }
  }
}

VS Code

Merge this server into .vscode/mcp.json. Use MCP: List Servers to start us-federal-regulations-cfr-mcp and inspect its tools.

VS Code configuration

{
  "servers": {
    "us-federal-regulations-cfr-mcp": {
      "type": "http",
      "url": "https://rules.openkrill.app/mcp"
    }
  }
}

Gemini CLI

Run this once. It writes .gemini/settings.json in the current project; pass --scope user for ~/.gemini/settings.json.

Gemini CLI configuration

gemini mcp add --transport http us-federal-regulations-cfr-mcp https://rules.openkrill.app/mcp

Claude Desktop

Merge this into claude_desktop_config.json (macOS: ~/Library/Application Support/Claude/, Windows: %APPDATA%\Claude\), then restart Claude Desktop.

Claude Desktop configuration

{
  "mcpServers": {
    "us-federal-regulations-cfr-mcp": {
      "url": "https://rules.openkrill.app/mcp"
    }
  }
}

Windsurf

Merge this into ~/.codeium/windsurf/mcp_config.json, then refresh MCP in Cascade. Windsurf remote servers use serverUrl, not url.

Windsurf configuration

{
  "mcpServers": {
    "us-federal-regulations-cfr-mcp": {
      "serverUrl": "https://rules.openkrill.app/mcp"
    }
  }
}

See all 248

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