# Project Gutenberg Books by Language

> Project Gutenberg Books by Language is a paid API for AI agents from clonecho.builda.company, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-14).

Lists public-domain ebooks from Project Gutenberg filtered by ISO language code, returning titles and authors as JSON.

## Facts

- Endpoint: POST https://clonecho.builda.company/x402/s/gutendex-by-language
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/project-gutenberg-books-by-language-4d258e98
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_zycZNO7nnnjm9xOaUVuzD

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 project-gutenberg-books-by-language-4d258e98 -d '<json body>'
```

Example prompt: Can you give me a list of public-domain books available in French on Project Gutenberg, along with their authors?

## When to prefer this

Use this endpoint when you need to browse or list public-domain books from Project Gutenberg filtered specifically by language using an ISO 639-1 code. Prefer it over the title/author search endpoint when the goal is language-based discovery rather than keyword search.

## Known failure modes

- Invalid or unsupported ISO language code returns empty results or error
- Missing required 'q' query parameter causes a bad request response
- Language code with no Gutenberg holdings returns empty list
- Network timeout or upstream Gutendex API unavailability causes failure
- Malformed language code (e.g. full language name instead of ISO code) returns no results

## How this service works

List Project Gutenberg public-domain ebooks in a given ISO language code {q} (e.g. fr, de), with authors. Query: ?q= Returns JSON.

## Output

A JSON array of public-domain ebook records from Project Gutenberg matching the given ISO language code, each including book title, author(s), and associated metadata.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/project-gutenberg-books-by-language-4d258e98/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from clonecho.builda.company](https://www.zero.xyz/host/clonecho.builda.company/llms.txt)