eCFR

About

Connects to the public eCFR API and returns parsed regulatory text. You can fetch sections, subparts and parts, browse the CFR structure, search the full text, check version history and corrections, and compare a section at two dates. Convenience tools look up FAR and DFARS clauses and FAR 2.101 definitions.

Runs as a hosted streamable HTTP endpoint at https://ecfr.1102tools.com/mcp, or locally with the ecfr-mcp package via uvx. No sign-in or API key is needed, hosted or local.

What you can do

• Get parsed text of CFR sections, subparts, parts and appendices
• Look up FAR, DFARS and agency supplement clauses by number
• Full-text search across the CFR with title, chapter and part filters
• Compare a section's text at two dates and see what changed
• Find sections changed since a given date
• Find term definitions in FAR 2.101
• View version history and editorial corrections
• Browse CFR structure and list agencies

Tools 13

• compare_versionsRead-only

  Compare a CFR section's text at two dates and list added, removed or changed paragraphs.

• find_far_definitionRead-only

  Find a term's definition in FAR 2.101, with other paragraphs that mention it.

• find_recent_changesRead-only

  List CFR sections amended or removed since a given date.

• get_ancestryRead-only

  Get the breadcrumb hierarchy path for a section, part or appendix.

• get_cfr_contentRead-only

  Get the parsed full text of a CFR section, subpart, part or appendix.

• get_cfr_structureRead-only

  Get the hierarchical table of contents for a CFR title or subset.

• get_correctionsRead-only

  Get editorial corrections for a CFR title, newest first.

• get_latest_dateRead-only

  Get the most recent available date for a CFR title.

• get_version_historyRead-only

  Get the version history of a CFR section, subpart or part.

• list_agenciesRead-only

  List agencies with their CFR title and chapter references.

• list_sections_in_partRead-only

  List all sections and appendices in a CFR part with headings.

• lookup_far_clauseRead-only

  Look up current text of a FAR, DFARS or supplement section or clause.

Read from the live server on 6 Nov 2026. Read-only, Writes and Can delete are hints the server declares; your client decides whether to ask before running a tool.

Example prompts

• Pull the current text of FAR 15.305 and summarize what it requires.

• Compare FAR 52.212-4 between 2024-01-01 and 2025-01-01 and show what changed.

• Look up the FAR definition of 'commercial product' in 2.101.

• What FAR sections were amended in the last 6 months?

Set up

Every client connects to ecfr.1102tools.com. Pick yours; the page remembers your choice.

claude mcp add --transport http ecfr https://ecfr.1102tools.com/mcp

https://ecfr.1102tools.com/mcp

{
  "mcpServers": {
    "ecfr": {
      "url": "https://ecfr.1102tools.com/mcp"
    }
  }
}

code --add-mcp '{"name":"ecfr","type":"http","url":"https://ecfr.1102tools.com/mcp"}'

{
  "servers": {
    "ecfr": {
      "type": "http",
      "url": "https://ecfr.1102tools.com/mcp"
    }
  }
}

{
  "mcpServers": {
    "ecfr": {
      "serverUrl": "https://ecfr.1102tools.com/mcp"
    }
  }
}

codex mcp add ecfr --url https://ecfr.1102tools.com/mcp

[mcp_servers.ecfr]
url = "https://ecfr.1102tools.com/mcp"

gemini mcp add --transport http ecfr https://ecfr.1102tools.com/mcp

{
  "mcpServers": {
    "ecfr": {
      "type": "http",
      "url": "https://ecfr.1102tools.com/mcp"
    }
  }
}

Embed

Show eCFR in a README or on your site. Each embed links to this page, uses the server’s own URL, and sets no cookies. How embeds work

The card, the iframe and the JSON are in English. Add ?lang=it, fr, de or es to their address for another language.

README badge Website card iframe JSON AI prompt

README badge

Markdown

[![eCFR on mcp.tc](https://mcp.tc/i/ecfr/badge.svg)](https://mcp.tc/i/ecfr)

HTML

<a href="https://mcp.tc/i/ecfr"><img src="https://mcp.tc/i/ecfr/badge.svg" alt="eCFR on mcp.tc" height="20"></a>

It follows the reader’s light or dark mode. Add ?theme=light or ?theme=dark to fix it, or ?style=compact to show the mark without the word.

Website card

HTML

<script src="https://mcp.tc/w/ecfr.js" async></script>

The card appears where the tag is. Add data-theme="dark" or data-size="compact" to the tag to change it. The file holds everything it needs, so it makes no other requests and sets no cookies.

iframe

HTML

<iframe src="https://mcp.tc/embed/ecfr" title="eCFR on mcp.tc" width="420" height="200" loading="lazy" allow="clipboard-write" style="border:0;border-radius:8px;max-width:100%"></iframe>

Use it on pages that don’t allow scripts. Add ?theme=light or ?theme=dark to the address to fix the colors.

JSON

The listing as data for your own pages and tools: name, tagline, the server’s own URL, tools and the “Add to” links. Any site can read it (CORS is open).

https://mcp.tc/i/ecfr.json

What each field means

AI prompt

Paste this into an AI coding assistant, such as Claude Code or Cursor, and it adds the eCFR card to your site.

Markdown

Add the mcp.tc card for eCFR, an MCP server, to my website. It is one static script: no build step, no package to install, no cookies.

Put this tag where the card should appear. The card renders right before it:

```html
<script src="https://mcp.tc/w/ecfr.js" async></script>
```

To show the card somewhere else, put this placeholder there and load the same script once, for example before `</body>`. Keep the link inside: visitors without JavaScript see it.

```html
<div data-mcptc="ecfr"><a href="https://mcp.tc/i/ecfr">eCFR on mcp.tc</a></div>
```

Options:
- `data-theme="light"` or `"dark"` on the tag or the placeholder fixes the colors. Without it, the card follows the visitor’s light or dark mode.
- `data-size="compact"` gives a smaller card without the tagline.
- The CSS variable `--mcptc-max-width` on the placeholder or a parent sets the width (default `520px`).
- `?lang=` on the script URL sets the card’s language: `en`, `it`, `fr`, `de` or `es`.

If the site has a Content Security Policy, allow `script-src https://mcp.tc` and `img-src data:` (the icon is inline).

For a README or other Markdown docs, use the badge instead:

```markdown
[![eCFR on mcp.tc](https://mcp.tc/i/ecfr/badge.svg)](https://mcp.tc/i/ecfr)
```

Reference: https://mcp.tc/embed

Change history

We read this server’s tool list every 3 hours and record what changes. Last read 7 Nov 2026, 14:43 UTC.

1. 3 Nov 2026, 08:52 UTC, Automatic check

   New version 1.1.15 (was 1.1.14). Reported by the server.

2. 1 Nov 2026, 05:22 UTC, Automatic check

   Tracking started: 13 tools.

FAQ