# keyronne.com Book ISBN Lookup

> keyronne.com Book ISBN Lookup is a paid API for AI agents from keyronne.com, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-15).

Look up book metadata by ISBN (10 or 13 digit), returning title, authors, publishers, publish date, page count, subjects, and cover image from Open Library

## Facts

- Endpoint: POST https://keyronne.com/api/book
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/keyronne-com-book-isbn-lookup-8cdf145a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_XRYLVmTSc23hiIJk6DXap

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 keyronne-com-book-isbn-lookup-8cdf145a -d '<json body>'
```

Example prompt: Can you look up the book with ISBN 9780140328721 and tell me the title, authors, and publisher?

## When to prefer this

Use this endpoint when you need structured bibliographic metadata for a known ISBN, especially when you also want ISBN check-digit validation before lookup. Prefer this over general web search when you need clean structured fields (authors, publishers, subjects, cover image) rather than free-text results. Good for enriching catalogs, verifying book data, or resolving an ISBN into human-readable metadata.

## Known failure modes

- Invalid ISBN check digit — returns rejection error before making data lookup
- ISBN not found in Open Library — returns not-found response
- Malformed input (non-numeric characters after stripping hyphens/spaces) — returns validation error
- ISBN has wrong length (not 10 or 13 digits) — returns format error
- Network timeout reaching Open Library — returns upstream error

## How this service works

Look up a book by ISBN (10 or 13 digit): title, subtitle, authors, publishers, publish date, page count, subjects, and cover image. Validates the ISBN check digit first (rejecting typos unpaid) and returns both ISBN forms. Data from Open Library; attributed in every response. POST a JSON body like: {"isbn":"9780140328721"}

## Output

Returns a JSON object with the book's title, subtitle, authors list, publishers list, publish date, page count, subject tags, cover image URL, and both ISBN-10 and ISBN-13 forms. Also confirms the ISBN check digit is valid. Data is sourced from Open Library with attribution included in every response.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "isbn": {
   "type": "string",
   "description": "A 10- or 13-digit ISBN; hyphens and spaces are ignored."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/keyronne-com-book-isbn-lookup-8cdf145a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from keyronne.com](https://www.zero.xyz/host/keyronne.com/llms.txt)