# x402 Books Search API

> x402 Books Search API is a paid API for AI agents from workspace-x402-paywall.onrender.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-11).

Searches for books by query string and returns relevant book metadata, priced at $0.005 USDC per call via x402 micropayment

## Facts

- Endpoint: GET https://workspace-x402-paywall.onrender.com/ref/books?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-books-search-api-b7db2a4a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2zvhnNLU0flc-Un00-pRA

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability x402-books-search-api-b7db2a4a
```

Example prompt: Search for books about machine learning and return the name and price for each result.

## When to prefer this

Use this endpoint when you need a pay-per-call, no-subscription book search with micropayment via USDC on Base or Solana. It is ideal for agents that need occasional book lookups without committing to a monthly API plan, and when you want to filter returned fields to keep responses lean.

## Known failure modes

- Missing required 'q' parameter returns an error
- Empty query string may return zero results
- Invalid field names in 'fields' parameter may be ignored or cause errors
- Payment failure via x402 (insufficient USDC balance or wrong network) blocks the request
- Service may be slow or unavailable on Render's free tier (cold starts)
- Overly generic queries may return irrelevant or empty results

## How this service works

66 pay-per-call APIs: AI text/image generation ($0.01), Polymarket odds, crypto prices, DeFi yields, FX rates, weather, IP/geo, FBI wanted, SEC tickers, clinical trials, 250M academic papers, Stack Overflow, meme-coin launchpads (pump.fun, Clanker, Four.meme, SunPump), tokenized stocks, Solana top 100, and 40+ more. $0.005/call standard. USDC on Base and Solana via x402.

## Output

Returns a JSON object containing book records matching the search query, with fields such as name and price_usd depending on the fields parameter supplied. The response schema is open-ended and may include title, author, price, and other catalog metadata.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "q"
     ],
     "properties": {
      "q": {
       "type": "string",
       "description": "Requires a text search query string"
      }
     }
    }
   },
   "additionalProperties": false
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-books-search-api-b7db2a4a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from workspace-x402-paywall.onrender.com](https://www.zero.xyz/host/workspace-x402-paywall.onrender.com/llms.txt)