agentlookups.ai / docs / GroundRules

GroundRules documentation

GroundRules helps you find US law. Give it an address and it names every government that makes law there (federal, state, county and city), with each one's code and official source. Search by topic, question or citation, then read the original text with its citation, source link and date. It works on its website, through an AI assistant over MCP, and as a plain HTTPS API.

Where the data comes from

Federal law. The United States Code, from the Office of the Law Revision Counsel of the US House, and the Code of Federal Regulations, from the eCFR (Office of the Federal Register and Government Publishing Office).
State and local law. State statutes, and some state regulations and local codes, collected from each government's own downloads and websites.
Dated copies. Where a state does not publish its code in a form GroundRules can collect, it starts from a dated copy: the publisher's own pages saved by the Internet Archive, the state's files as republished by Public.Resource.Org, or the Open US Law dataset. Sections from a copy say so beside the text, with the copy's date.
Locations. Addresses are placed on the map by the US Census Bureau's public geocoder, which also names the state, county and city.

GroundRules copies the legal text and leaves out publisher commentary and indexes. It writes no summaries. It keeps the source files so any section can be checked against them. The dates and section counts for each source come from its build files, not from hand-typed lists; see coverage. The how it works page has more.

Cost and access

GroundRules is free during beta, with no account and no API key needed. Features, access and pricing may change. Rate limits apply.

Connect it

Claude (web and desktop)

These are Claude's steps as of September 2026. Open Customize > Connectors, click the plus button, then Add custom connector. Name it GroundRules and paste https://law.agentlookups.ai/mcp as the URL. No authentication is needed, so leave the OAuth fields under Advanced settings empty, and click Add. To use it in a conversation, click the plus button at the lower left, open Connectors and turn GroundRules on.

On a Team or Enterprise plan, an owner adds it first under Organization settings > Connectors (Add, then Custom, then Web). Members then find it under Customize > Connectors. See Claude's setup guide.

Claude Code

claude mcp add --transport http groundrules https://law.agentlookups.ai/mcp

This adds it for the current project only. Add --scope user to use it in every project.

ChatGPT

These are OpenAI's steps as of September 2026. Turn on Developer mode under Settings > Security and login. Open Plugins, click the plus button, give it a name, and enter https://law.agentlookups.ai/mcp as the MCP server URL, with no authentication. Then start a new conversation and pick GroundRules from the tools menu. Whether Developer mode is offered depends on your account and workspace. See OpenAI's setup guide.

Other MCP clients

Add a remote MCP server with the URL https://law.agentlookups.ai/mcp, transport Streamable HTTP, no authentication. Menu names differ by client. The client should find four tools.

To test the endpoint by hand, list its tools:

curl -X POST https://law.agentlookups.ai/mcp \
  -H 'content-type: application/json' \
  -H 'accept: application/json, text/event-stream' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

Plain HTTPS API

The same search, as a GET request that returns JSON:

https://law.agentlookups.ai/v1/search?q=security%20deposit%20refund&jurisdictions=us-tx

Other endpoints: /v1/resolve?address= (the governments at an address), /v1/section/<id> and /v1/lookup?citation= (one section), POST /v1/sections (up to 10 sections) and /v1/coverage. Agent-facing notes, with every parameter, are in llms.txt.

The tools

All four are read-only.

law_for_location (address, or lat and lon): names every level of government at that point, each with its code sources, official links, dates, and whether GroundRules holds the text.
law_search (q, optional jurisdictions or address): searches the text GroundRules holds by topic, question or citation, and returns original-text snippets, each with its citation, source link and date.
law_get_section (id, citation, or up to 10 references): returns the full text of a section with its source, date, place in the code, and the sections before and after it.
law_coverage (no arguments): lists every source GroundRules holds, with its section count, date, and a flag if it has fallen behind its publisher.

With no scope, a search that names one state covers that state plus federal law. To pick the scope yourself, pass jurisdictions as ids from law_coverage: us- plus the lowercase two-letter code for a state (such as us-tx), us for the US Code and federal regulations, or us-cfr for federal regulations alone.

Example prompts

Each prompt was run live on September 28, 2026, with the arguments an assistant would send. Results change as the law and the collection change.

"What law applies at 1100 Congress Ave, Austin, TX 78701?"

Call: law_for_location {"address": "1100 Congress Ave, Austin, TX 78701"}

Came back: the Census geocoder matched the address (the Texas Capitol). Four levels: federal (the US Code and federal regulations, both held), Texas (the Texas Statutes held; the Texas Administrative Code named with its official link but not held), Travis County and the city of Austin. For the county and city, the answer says GroundRules does not hold their code text and names the three online libraries where a local code is most likely published.

"What is the Texas deadline for a landlord to refund a security deposit on an apartment?"

Call: law_search {"q": "What is the Texas deadline for a landlord to refund a security deposit on an apartment?"}

Came back: a search of federal and Texas law. The top result was Tex. Property Code § 92.103, which reads in part: "Except as provided by Section 92.107, the landlord shall refund a security deposit to the tenant on or before the 30th day after the date the tenant surrenders the premises." It carried its link to the Texas Legislative Council and the label "current through 89th 2nd Called Legislative Session, 2025". The next two results were § 93.005 (commercial leases) and § 94.103 (manufactured home lots). Which section fits a given lease is for you or your assistant to judge.

"Show me the full text of 42 U.S.C. 3604."

Call: law_get_section {"citation": "42 U.S.C. 3604"}

Came back: the full section, "Discrimination in the sale or rental of housing and other prohibited practices" (part of the Fair Housing Act), with a link to its source file from the Law Revision Counsel, current through Public Law 119-111 (09/18/2026), and not marked stale.

"What is the Georgia deadline for a landlord to return a security deposit? How current is that text?"

Call: law_search {"q": "What is the Georgia deadline for a landlord to return a security deposit?"}

Came back: a search of federal and Georgia law. The top result was O.C.G.A. § 44-7-34: "Within 30 days after obtaining possession of the premises as provided in subsection (b) of Code Section 44-7-33, a landlord shall return to the tenant the full security deposit which was deposited with the landlord by the tenant." Beside it came the vintage label "Public.Resource.Org bulk O.C.G.A., Release 86 (2022-11), retrieved 2026-09-17". That marks a dated snapshot, not current law: Georgia stopped publishing its code as a download, so this text leaves out laws passed after the 2022 session. Check Georgia's official code before relying on it.

"Which places does GroundRules cover, and how current is each one?"

Call: law_coverage {}

Came back: 56 sources, all held, covering federal law, all 50 states, DC, Guam and New York City, each with its section count and date. Ten carried a vintage label (dated snapshots); none was marked stale.

How to read results

Every successful answer carries the notice "GroundRules: Original legal text. Not legal advice." The service's honesty rules, quoted from its llms.txt, which an assistant should pass on and not override:

Verbatim text only: we never summarize, characterize, or rank law by importance; the calling agent interprets.

Every record names its official source; the official source is authoritative, we are not.

Absence is never an answer: when we do not host a jurisdiction's text, the response says exactly that and points at where the text lives when known.

Vintage-labeled text is a dated snapshot, not current law; relay the label with the text.

Not legal advice; no individualized guidance.

Location answers (`law_for_location`)

matched_address: the address the Census geocoder matched. Check that it is the place you meant.
stack: one entry per level: federal, state, county, and place (a city or town). Each lists its code sources with the publisher and official_url.
hosted: true: GroundRules holds that text and can search it. hosted: false: it names the code and where it lives, but does not hold the text.
honesty: plain-language notes on gaps. For example, an address outside any city or town gets the county code as its local code and a note that no city code applies.

Search results and sections (`law_search`, `law_get_section`)

citation, heading, snippet or body: the original words, as published.
source_url: the publisher's file or page. html_url (on search results): a readable GroundRules page for the section.
current_through: how current the publisher says the text is, read from the publisher when the collection is built. It reflects a publication date, edition or archive date, not necessarily the date a law took effect.
vintage: when set, the text is a dated snapshot. In the service's words, "vintage-labeled text is NEVER current law". Keep the label with the text.
stale: true: a regular check found the source behind its publisher. Read the publisher's current text.
searched_sources: what the search covered. missing_sources: ids you asked for that GroundRules does not hold. note: how the search picked its scope, and any ids it does not hold.
No hits: nothing matched in the sources searched. In the service's words, "Missing coverage remains distinct from no matching sections." Neither one means no law applies.

Limits

Not legal advice, and no individual guidance. It does not say whether a law applies to you or what it means. A section can match your question without applying to your situation.
It holds statutes, regulations and codes. It holds no court decisions and no records about people, and it is not a background check.
It does not score or rank laws. Search order reflects how well the text matches your words, not how much a law matters.
A no-match proves nothing. An empty search, or a place whose code GroundRules does not hold, never means no law applies there.
Coverage has gaps. Most county and city codes are not held (about half of US municipalities publish no code online), many state regulations are not held, and some state text is a dated snapshot. For what is held today, call law_coverage or open the coverage page rather than relying on a copied list.
US law only. The official source is authoritative, not GroundRules.

Troubleshooting

HTTP 429. Too many requests from your network address in a short time. Wait, then retry, and space out automated calls.
"the Census geocoder did not match this location". Give a one-line street address with the city, the two-letter state code and the ZIP code, such as "1100 Congress Ave, Austin, TX 78701", or pass lat and lon. Always check matched_address: the geocoder can match a similar address nearby.
Two-letter state codes. In addresses, use the two-letter code, such as TX, not Texas. In jurisdictions, use us- plus the lowercase code, such as us-tx. A bare "TX" or "texas" matches no source and comes back in missing_sources.
Not covered. The answer says so (hosted: false, missing_sources, or an honesty note) and points to where the text lives when known. Follow that link. law_coverage is the full list of what is held: if it lists a place that a location answer marked hosted: false, search that place by its id in jurisdictions, such as us-md.
No match. Try a shorter phrase or other words, or mode: "keyword" for plain word matching. Check searched_sources; if the state you expected is missing, search again with its id in jurisdictions, such as us-tx.
"Citation not found. Try search with the state and code name." Citation styles vary. Search with the state and code name, then use the citation or id the result gives, such as "Tex. Property Code § 92.103".
The connector will not connect. Check that the URL ends in /mcp and that no authentication is set, then run the curl test above.
A record looks wrong. Email corrections@agentlookups.ai with the page link or citation and a short description: missing text, a wrong date, a broken link, or a search that does not work. We check reports against the saved source files and the publisher, then correct or annotate the record. See report an error.
Anything else. support@agentlookups.ai.

Privacy and terms

No account, no cookies, no trackers. GroundRules does not log the search page, law pages, /v1 or /mcp requests at all, not even the path. The one exception: if a request fails partway, the web server writes an error line that includes the address requested. Other page visits, such as the coverage page, are logged. Page logs and error lines are deleted after 14 days. To find a location, it sends the address or map coordinates to the US Census Bureau's geocoder. It keeps recent typed addresses in memory for up to 15 minutes to answer repeats faster and never writes them to disk. One privacy page and one set of terms cover all six agentlookups.ai services.

GroundRules is run by TopHat Monkey Software LLC.

Last updated: September 28, 2026