Find US federal + state appellate judges by name in CourtListener's People DB. Query by firstName (case-insensitive prefix), lastName (case-insensitive prefix), or both — at least one required. Returns id, full name + components, dates of birth/death, gender, education (school, degree level, year), political affiliations (party + appointing executive period), count of distinct judicial positions, and canonical CourtListener URL per match. Pairs with law.case-search + law.attorney-lookup to complete the WHO graph of a legal research workflow. Backed by CourtListener (Free Law Project); underlying data is public domain.
/api/law/judge-lookupPAYMENT-SIGNATURE.The judge lookup API is a pay-per-call law endpoint built for AI agents and autonomous software. Find US federal + state appellate judges by name in CourtListener's People DB.
There is no signup and no API key. An agent (or any HTTP client) hits the endpoint, receives an x402 "402 Payment Required" challenge, signs a sub-cent USDC payment on Base or Solana, and retries — the data comes back on the paid request. That makes it a drop-in judge lookup data source for an agent tool-use loop, an MCP host, or a backend that needs law data on demand without onboarding to yet another vendor portal.
| Name | Type | Description |
|---|---|---|
firstName | string | First-name prefix to search (case-insensitive). "Son" matches "Sonia". Optional, but at least one of firstName/lastName required. min 2 chars · max 100 chars |
lastName | string | Last-name prefix to search (case-insensitive). "Soto" matches "Sotomayor". Optional, but at least one of firstName/lastName required. min 2 chars · max 100 chars |
limit | integer | Max judge records to return (1-50). Default 10. min 1 · max 50 |
# 1. Probe with no auth → 402 envelope with PaymentRequirements curl -sS 'https://2s.io/api/law/judge-lookup?firstName=xx&lastName=xx&limit=10' # 2. Sign + retry with PAYMENT-SIGNATURE: curl -sS 'https://2s.io/api/law/judge-lookup?firstName=xx&lastName=xx&limit=10' \ -H 'PAYMENT-SIGNATURE: <base64-json-payload>' # Or use the canonical runner (handles probe → sign → retry): # EVM_PRIVATE_KEY=0x... node --env-file=.env.local \ # --experimental-strip-types scripts/x402-pay.ts \ # 'https://2s.io/api/law/judge-lookup?firstName=xx&lastName=xx&limit=10'
import { TwoS } from '@2sio/sdk'
const client = new TwoS({
privateKey: process.env.EVM_PRIVATE_KEY as `0x${string}`,
})
const result = await client.law.judgeLookup({
"firstName": "xx",
"lastName": "xx",
"limit": 10
})
console.log('endpoint:', result.endpoint)
console.log('cost:', result.costUsd, 'USDC')
console.log('tx:', result.settlement?.txHash)
console.log('data:', result.data)import os
from twosio import TwoS
client = TwoS(private_key=os.environ["EVM_PRIVATE_KEY"])
result = client.law.judge_lookup(firstName="xx", lastName="xx", limit=10)
print("endpoint:", result.endpoint)
print("cost:", result.cost_usd, "USDC")
print("tx:", (result.settlement or {}).get("tx_hash"))
print("data:", result.data)// 1. Add @2sio/mcp to your MCP host config (Claude Desktop example below).
// EVM_PRIVATE_KEY funds x402 payments per call.
// claude_desktop_config.json
{
"mcpServers": {
"2sio": {
"command": "npx",
"args": ["-y", "@2sio/mcp"],
"env": { "EVM_PRIVATE_KEY": "0x..." }
}
}
}
// 2. Once the server is running, agents call this tool via standard MCP:
{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/call",
"params": {
"name": "law.judge-lookup",
"arguments": {
"firstName": "xx",
"lastName": "xx",
"limit": 10
}
}
}| Field | Type | Description |
|---|---|---|
ok | boolean | one of: true |
items | array | |
total | integer | Total matching rows upstream; null when unknown. |
source | object | |
meta | object |
{
"ok": true,
"items": [
{
"id": 1,
"name": "example",
"firstName": "example",
"middleName": "example",
"lastName": "example",
"suffix": "example",
"dateOfBirth": "example",
"dateOfDeath": "example",
"gender": "example",
"isJudge": false,
"education": [
{
"school": "example",
"degreeLevel": "example",
"degreeYear": 1
}
],
"politicalAffiliations": [
{
"party": "example",
"source": "example",
"startDate": "example",
"endDate": "example"
}
],
"positionCount": 1,
"url": "https://example.com",
"dateModified": "example"
}
],
"total": 1,
"source": {
"provider": "example",
"url": "example",
"license": "example"
},
"meta": {
"query": {
"firstName": "example",
"lastName": "example",
"limit": 1
}
}
}