US federal rules taking effect

io.github.joelp22-makerPublished by GitHub account joelp22-makerv1.0.0Updated Oct 24, 2026

Which published US federal rules take effect between two dates, and which CFR parts they amend?

VerifiedStreamable HTTPWeb executableKnowledge & MemoryBusiness & Commerce

Overview

AI-generated overview

A remote MCP server that lists published US federal final rules taking effect between two dates and checks claims about them against Federal Register records.

What you can do
List final rules taking effect between two dates, soonest first, optionally filtered by agency, with titles, CFR parts amended, DATES paragraphs and verbatim quotes from the Federal Register record. Retrieve everything held for one rule by document number, including publication date and a link to federalregister.gov. List agencies with rule counts and their soonest and latest effective dates. Find rules amending a given CFR title and part, such as 49 CFR 192. Verify a claim about a rule's effective date, agency or amended CFR parts against the stored record and quote.
When to use it
Useful when you need to know which US federal rules take effect in a date window, which rules touch a particular CFR part, or whether a stated effective date or agency is correct. Suited to compliance, regulatory and policy research where answers should be traceable to the Federal Register.
Requirements
A remote streamable-HTTP endpoint at referencesource.org; no account, API key or environment variable is declared. The README also describes an npm package run via npx as a stdio bridge, which needs Node 18 or later. Network access to the endpoint is required.
Before you install
Read-only lookups; no writing, sending or deleting. Verdicts describe what the stored source states, not what is true in the world, and not_found means only that the item is not in this register. It searches only its own published records and cannot check arbitrary pages. Standard server request logs apply.

Installation

In SourceWeft

  1. Open US federal rules taking effect in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.

Use with an agent

Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.

Read https://sourceweft.com/mcp/io.github.joelp22-maker%2Freferencesource-rules/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.

Read the install guide the agent follows

Other MCP clients

Add this to your client's mcpServers config.

{
  "mcpServers": {
    "us-federal-rules-taking-effect": {
      "type": "http",
      "url": "https://referencesource.org/mcp/rules"
    }
  }
}

README

referencesource-mcp

[referencesource.org MCP connector]

MCP server for referencesource.org — small, verified reference datasets where every record carries its source URL and a verbatim quote from that page, so any value an assistant gives you can be checked, not just believed.

285 datasets, 110,000+ records: regulatory thresholds and deadlines, version compatibility, standards supersessions, certification registers, inspection requirements, and more. Each dataset states its coverage and its last-verified date.

Tools

toolwhat it does
list_datasetsevery dataset with record counts and descriptions
search_recordssearch within a dataset; each hit returns the value plus its source URL and verbatim source quote
get_recordone record by id, full provenance included
verify_quotegive it a dataset slug and a value you already hold (record id and field optional) — it checks that claim against our published records and says whether it matches

verify_quote is the unusual one: assistants invent plausible-but-wrong values roughly 19% of the time in our own measurements, and this is the check. Four verdicts come back:

verdictwhat it means
matches_recordthe claim equals the stored value; the match type is named (exact, case-insensitive, normalised)
matches_quotenot a stored value, but it does appear in the record's source quote
differsthe record holds a different value — both are returned, with the source
not_foundno record in that dataset carries it

Where a record is found, the answer carries the stored value, the record URL, the source URL and the verbatim quote, so the claim can be traced upstream — plus an attestation saying plainly that the verdict is about what our source states, not about what is true in the world. Asking whether the 2026 conforming loan limit for Autauga County, Alabama is $806,500 returns differs, stored value $832,750, quoting the FHFA row it came from.

Scope, stated so nobody overclaims: these tools search referencesource.org's own published records. They do not fetch arbitrary URLs and cannot check a claim against a page we have not harvested. not_found means "not in this dataset", never "false".

Setup

Claude Desktop — add to claude_desktop_config.json:

json
{  "mcpServers": {    "referencesource": {      "command": "npx",      "args": ["-y", "referencesource-mcp"]    }  }}

Cursor / other stdio MCP clients — same idea: command npx, args ["-y", "referencesource-mcp"].

Clients that support remote servers directly don't need this package at all — point them at the streamable-HTTP endpoint: https://referencesource.org/mcp.

Notes

  • Zero dependencies; Node 18+. The package is a thin stdio→HTTPS bridge to the stateless server at referencesource.org/mcp.
  • No accounts, no keys, no tracking beyond standard server request logs (see referencesource.org/privacy).
  • Data is free to read on the site in HTML, Markdown, and JSON; this package just makes it callable mid-conversation.

MIT licensed.

The data behind it

Every record carries source (the page the value was read from) and source_quote (the verbatim line on that page which states it), so any answer this server returns can be checked against its source. verify_quote runs that check against a value you already hold: it tells you whether our record agrees, and hands back the source and quote either way.

Licence

MIT — see LICENSE. The reference data itself is CC BY 4.0; see the data repository for the full position on the quoted excerpts.

Source: README.md at commit e0de5e7

Tools

5

list_rules_taking_effect

List federal rules taking effect between two dates

What lands on me, and when? Lists already-published US federal final rules whose effective date falls between two dates, soonest first, optionally from one agency. Each with the rule title, the agency, the CFR parts amended, the document number, the rule's own DATES paragraph and a verbatim quote of the Federal Register record. This is the compliance-calendar question — use it for "what takes effect in Q4", not for searching the Federal Register by topic.

Parameterstorequiredfromrequiredlimitagency

get_rule

Get one rule by Federal Register document number

Everything this register holds for one final rule: title, agency, effective date, the rule's own DATES paragraph, the CFR parts it amends, its publication date, a link to the rule on federalregister.gov, and a verbatim quote of the Federal Register API record it was read from. Document numbers look like "2026-13685" and appear in every other tool's results.

Parametersdocument_numberrequired

list_agencies

List the agencies with rules taking effect

Which agencies have rules coming? Returns each agency in this register with how many rules it has taking effect, the soonest and latest of those dates. Call it to get an agency name exactly as the Federal Register writes it before filtering with list_rules_taking_effect — "Federal Aviation Administration", not "FAA".

Parametersquery

list_rules_amending_cfr_part

List rules amending a CFR part

Is anything changing in the part of the CFR I am subject to? Give a CFR title and part — "49 CFR 192", "40 CFR 52", "21 CFR 1308" — and get the already-published final rules that amend it, soonest effective date first, with each rule's DATES paragraph and a verbatim quote. The part is matched whole, so "40 CFR 5" never returns rules about 40 CFR 52.

Parametersfromlimitcfr_partrequired

verify_quote

Check a claimed fact about a rule against the register

Is this right? Check a claim about a final rule — its effective date, its agency, the CFR parts it amends — against the Federal Register record instead of trusting it. Says whether the claim matches a stored value, appears only in the verbatim quote, or differs (and then what the record says instead). Effective dates are exactly where a confident wrong answer costs money.

Parametersfieldclaimed_valuerequireddocument_numberrequired

Version history

1
  1. v1.0.0LatestSep 21, 2026

Score

100% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 daysRequired25 pts
  • Auth declaredRequired10 pts
  • Tools listedRequired15 pts
  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts