@pipeworx/fjc-judges

Biographies and appointment records of every US federal (Article III) judge since 1789 — Supreme Court justices, court of appeals and district court judges — from the Federal Judicial Center's Biographical Directory.

Part of Pipeworx — an MCP gateway connecting AI agents to 1800+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.

Tools

• fjc_judge_lookup(name) — one judge's full record: every appointment with court, title, appointing president and party, ABA rating, nomination / hearing / confirmation / commission dates, Senate vote, chief-judge and senior-status dates and how service ended; plus birth, death, education and career. Answers "who appointed Judge X", "when was X confirmed", "is X still serving".

• fjc_judges_by_court(court, status?) — judges of one court (e.g. "Ninth Circuit", "Southern District of New York", "Supreme Court"). status is active (default — active service only), serving (active or senior) or all.

• fjc_judges_by_president(president, court_type?) — every Article III appointment a president made, with totals by court level. Joseph R. Biden: 235 appointments of 230 distinct judges (one judge can be appointed twice, e.g. Ketanji Brown Jackson to the D.C. Circuit and then the Supreme Court).

Every response carries source, licence and data_as_of (when the FJC last regenerated the directory).

Related MCP server: CourtListener MCP Server

Auth

Keyless.

Data sources

• Federal Judicial Center, Biographical Directory of Article III Federal Judges, 1789–present. Public domain (a work of the US federal government).

The FJC publishes the directory as a single export (~5 MB, ~4,000 judges, regenerated daily), not as a query API. The pack reads it per isolate and keeps the parsed rows for up to six hours, so the first call on a cold isolate takes about a second and the rest take milliseconds.

Things the next person would otherwise rediscover:

• One row per judge, with up to six appointments flattened into numbered columns (Court Name (1) … (6)). A judge elevated from district court to a circuit has two appointments; counts "by president" are appointments, and the response reports distinct judges alongside.

• Empty cells are frequently a single space, not empty — trim before testing.

• "Active" means no termination date and no senior-status date on that appointment. Senior judges still hear cases; use status: "serving" to include them.

• Presidents are written as the FJC writes them ("George H.W. Bush", "Joseph R. Biden"). A surname that matches two presidents returns ambiguous_president with both candidates rather than merging them.

• Magistrate, bankruptcy and state judges are not Article III judges and are not in this directory.

Quick Start

Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):

{
  "mcpServers": {
    "fjc-judges": {
      "url": "https://gateway.pipeworx.io/fjc-judges/mcp"
    }
  }
}

What this endpoint actually serves

tools/list at https://gateway.pipeworx.io/fjc-judges/mcp returns the tools in the table above plus the shared Pipeworx meta-tools — ask_pipeworx, discover_tools, search_within, remember/recall and the rest of the gateway-wide set. So the tool count you see is larger than this table: a single-pack endpoint currently lists roughly 30 shared tools alongside the pack's own. The connection's initialize response states its exact scope, and is the authoritative answer for a given day.

This is deliberate, not multiplexing by accident. The meta-tools are what let a scoped connection answer a question this pack does not cover — via ask_pipeworx, which routes across the whole catalog — without you adding a second MCP server. There is currently no way to mount a pack endpoint without them; if the extra schemas cost you more context than the routing is worth, connect to the full gateway once rather than to several pack endpoints.

Or connect to the full Pipeworx gateway to get every pack's tools listed directly, instead of just this one's:

{
  "mcpServers": {
    "pipeworx": {
      "url": "https://gateway.pipeworx.io/mcp"
    }
  }
}

Both URLs reach the same gateway and the same 1800+ data sources. The only difference is which pack's tools are listed directly; ask_pipeworx reaches all of them from either one.

No MCP client? Call it over HTTP

curl -X POST https://gateway.pipeworx.io/v1/tools/fjc_judge_lookup \
  -H 'Content-Type: application/json' \
  -d '{"name":"Ketanji Brown Jackson"}'

No account needed for the first calls. Inspect any tool: GET https://gateway.pipeworx.io/v1/tools/fjc_judge_lookup. Find one: POST https://gateway.pipeworx.io/v1/tools/search_packs with {"query":"..."}.

Standalone (no gateway account)

This package also runs as a local stdio MCP server — no Pipeworx account, no gateway round-trip:

{
  "mcpServers": {
    "fjc-judges": {
      "command": "npx",
      "args": ["-y", "@pipeworx/mcp-fjc-judges"]
    }
  }
}

Or run it directly to confirm it starts:

npx -y @pipeworx/mcp-fjc-judges

It speaks MCP over stdin/stdout and answers initialize/tools/list/tools/call for only this pack's tools — none of the shared meta-tools the gateway connection above adds. Same source, same tools, no ask_pipeworx routing.

Using with ask_pipeworx

Instead of calling tools directly, you can ask questions in plain English — this works on the pack endpoint above as well as on the full gateway:

ask_pipeworx({ question: "your question about Fjc Judges data" })

The gateway picks the right tool and fills the arguments automatically.

More

• Docs and guides

• pipeworx.io

License

MIT