MCP: U.S. case law for AI assistants

Add this URL to Claude, ChatGPT or any MCP client and the assistant can search U.S. opinions, read them, trace citing cases, and verify that every citation it gives you actually exists. No sign-up, no API key.

Setup

Claude.ai / Claude Desktop	Settings → Connectors → Add custom connector, paste the URL.
Claude Code	claude mcp add --transport http tailexi-us https://us.tailexi.org/mcp
ChatGPT	Settings → Apps & Connectors → enable Developer mode → Create, paste the URL.
Cursor / VS Code	{"mcpServers": {"tailexi-us": {"url": "https://us.tailexi.org/mcp"}}}

Tools

search_cases	Search U.S. case law: plain English, Terms & Connectors, citations, case names; filter by court level, state, circuit, year.
get_case	Read a case: Bluebook citation, metadata, later courts' descriptions, opinion list and full text in chunks.
get_citing_cases	Later cases citing a case, by depth or date, with the citing sentence; search within them for negative treatment.
get_authorities	The cases an opinion relies on, most heavily cited first.
get_parentheticals	How later courts describe a case ("holding that …").
verify_citations	Check every citation in a draft: exists? right case name? Catches invented citations.

Try asking

• “What are the most-cited Ninth Circuit decisions on qualified immunity and excessive force in the last ten years?”
• “Which state supreme courts rely most on Strickland v. Washington? Has any court said it was overruled?”
• “Check every case citation in this draft brief and tell me which ones don’t exist.”

Limits

120 requests per minute and 10,000 per day per source. Citing references are not a citator. Not legal advice.