law.judge-lookup

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.

price

$0.0036 USDC per call

method

GET/api/law/judge-lookup

payment

x402 v2 · USDC on Base (EIP-3009) or Solana (SPL transfer)

auth

None. Sign the payment, retry with PAYMENT-SIGNATURE.

tier

Tier 0 — no paid upstream

Parameters

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

Code samples

cURLbash

# 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'

TypeScript / Node — @2sio/sdktypescript

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)

Python — 2siopython

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)

MCP — Claude Desktop / AgentKit / any MCP hostjson

// 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
    }
  }
}

Response

Field	Type	Description
`query`	object
`returned`	integer
`judges`	array
`source`	object

Example response datajson

{
  "query": {
    "firstName": "example",
    "lastName": "example",
    "limit": 1
  },
  "returned": 1,
  "judges": [
    {
      "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"
    }
  ],
  "source": {
    "provider": "example",
    "url": "https://example.com",
    "license": "example"
  }
}

Discovery

/api/directory — full catalog of every endpoint
/openapi.json — OpenAPI 3.1 spec (per-op x-payment-info, x402Payment security)
/.well-known/x402 — machine-readable service descriptor for x402-aware crawlers
/.well-known/mcp/server-card.json — MCP SEP-1649 server card
/llms.txt — plain-text manifest for LLM ingestion

2s.io is x402-native. Every call is paid per-request from a USDC-funded EVM wallet on Base — no signup, no API keys, no monthly fees. Source code: github.com/2s-io/sdk.