LawDiver MCP

A legal MCP server your AI can actually cite

The LawDiver MCP server puts 10M+ verified U.S. opinions inside your AI assistant. Install the official ChatGPT app or connect Claude from its directory — then the assistant searches, reads, and cite-checks against the real corpus instead of recalling authority from memory.

Create a free account

Setup guides — official connectors

ChatGPTOfficial app ChatGPT setup guide

ClaudeOfficial app Claude setup guide

Specialty MCP guides (separate servers)

Claude Tax directory Claude Tax setup ChatGPT Tax Claude Trademark directory Claude Trademark setup ChatGPT Trademark

Why connect an opinion database at all?

A general-purpose model asked for a citation will produce something that looks like one. Courts have sanctioned lawyers over exactly that. An MCP connection changes where the authority comes from: instead of recalling a case, the assistant queries a database of real opinions and quotes what it finds — and you can follow every cite back to the full text.

What your assistant can do

Three tools, the same ones the REST API exposes, called by the model as it works.

Search cases

Semantic, boolean, and citation search across federal and state opinions, scoped by jurisdiction and court. Boolean exclusion is NOT, BUT NOT, or %. The assistant gets the passage that made each case relevant, not just a title.

Retrieve an opinion

Pull the full text and structured metadata — court, dates, holdings, citations — so the model reasons over the actual decision instead of a summary of it.

Check a citation

Confirm a case citation exists and report treatment, or verify specialty forms (Rev. Rul.) against held corpora. Specialty hits return authorityCoverage instead of a case candidate.

Stay inside your jurisdiction

Scope a session to one state, one circuit, or the U.S. Supreme Court, and the assistant cannot wander into authority that does not bind your court.

How it works

1. 1 ### Create an account

   Sign up with email and a password. You get an API key for editors and CLIs; Claude.ai uses OAuth Connect with the same account.

2. 2 ### Add LawDiver to your assistant

   ChatGPT: Install the official app from its ChatGPT listing. Claude.ai: Connect from the Claude directory (OAuth). Every other MCP client: use endpoint https://lawdiver.com/mcp with an API key header. Full per-assistant steps are below.

3. 3 ### Ask a legal question

   The assistant decides when to search, read, or cite-check. You see which tool it called and what came back — the research is auditable, not a black box.

4. 4 ### Follow the authority

   Every result carries the case name, citation, court, and date, and links to the full opinion on LawDiver so you can verify before you rely on it.

Prefer to call it yourself?

The MCP tools wrap the LawDiver API. The developer reference covers authentication, every endpoint and field, error codes, idempotency, and runnable examples.

See the API Read the documentation

LawDiver Enterprise — database queries for Claude or any other system, on its own endpoint. The database index lists what that database holds, by year.

Which agent are you using?

Choose your agent for the best setup instructions.

• OCOpenClaw
• HAHermes Agent
• CClaude.ai
• GPTChatGPT
• PxPerplexity
• CCClaude Code
• CxCodex
• GGrok Bot
• OOpenCode
• CuCursor
• …Other

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