book.search

Open Library book metadata search. Lookup by free-text query (matches title + author), or by individual title / author / ISBN (10 or 13 digit). Each record includes Open Library work key, title, author names + Open Library author keys, first publish year, edition count, cover image URL, sample ISBNs, publishers, languages, subject tags, fulltext flag, ebook access tier (public/borrowable/printdisabled/no_ebook), and canonical openlibrary.org URL. CC0 public-domain metadata.

price

$0.0012 USDC per call

method

GET/api/book/search

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
`q`	string	min 2 chars · max 200 chars
`title`	string	min 2 chars · max 200 chars
`author`	string	min 2 chars · max 200 chars
`isbn`	string	min 9 chars · max 17 chars
`limit`	integer	min 1 · max 50
`page`	integer	min 1 · max 100

Code samples

cURLbash

# 1. Probe with no auth → 402 envelope with PaymentRequirements
curl -sS 'https://2s.io/api/book/search?q=xx&title=xx&author=xx&isbn=xxxxxxxxx&limit=10&page=1'

# 2. Sign + retry with PAYMENT-SIGNATURE:
curl -sS 'https://2s.io/api/book/search?q=xx&title=xx&author=xx&isbn=xxxxxxxxx&limit=10&page=1' \
  -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/book/search?q=xx&title=xx&author=xx&isbn=xxxxxxxxx&limit=10&page=1'

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.book.search({
  "q": "xx",
  "title": "xx",
  "author": "xx",
  "isbn": "xxxxxxxxx",
  "limit": 10,
  "page": 1
})

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.book.search(q="xx", title="xx", author="xx", isbn="xxxxxxxxx", limit=10, page=1)

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": "book.search",
    "arguments": {
      "q": "xx",
      "title": "xx",
      "author": "xx",
      "isbn": "xxxxxxxxx",
      "limit": 10,
      "page": 1
    }
  }
}

Response

Field	Type	Description
`query`	object
`totalCount`	integer
`returned`	integer
`books`	array
`source`	object

Example response datajson

{
  "query": {
    "q": "example",
    "title": "example",
    "author": "example",
    "isbn": "example",
    "limit": 1,
    "page": 1
  },
  "totalCount": 1,
  "returned": 1,
  "books": [
    {
      "workKey": "example",
      "title": "example",
      "authorNames": [
        "example"
      ],
      "authorKeys": [
        "example"
      ],
      "firstPublishYear": 1,
      "editionCount": 1,
      "coverEditionKey": "example",
      "coverImageUrl": "example",
      "isbns": [
        "example"
      ],
      "publishers": [
        "example"
      ],
      "languages": [
        "example"
      ],
      "subjectTags": [
        "example"
      ],
      "hasFulltext": false,
      "ebookAccess": "example",
      "openlibraryUrl": "https://example.com"
    }
  ],
  "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.