# Suverse Gutenberg Books by Language

> Suverse Gutenberg Books by Language is a paid API for AI agents from proxy.suverse.io, paid per call via x402, $0.055/call, status unknown (last checked 2026-09-14).

Fetches Project Gutenberg public-domain books filtered by ISO language code and sorted by popularity via Gutendex

## Facts

- Endpoint: POST https://proxy.suverse.io/v1/data/suverse-gutenberg-by-language
- Price: $0.055/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/suverse-gutenberg-books-by-language-36b86ef8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_isLrnGd6sdd8DR66eYNV1

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 suverse-gutenberg-books-by-language-36b86ef8 -d '<json body>'
```

Example prompt: Can you pull a list of the most popular public-domain books available in French from Project Gutenberg? I want the count and book details sorted by popularity.

## When to prefer this

Choose this endpoint when you need to discover or enumerate public-domain books from Project Gutenberg filtered by a specific language without requiring an API key. It is especially useful for building multilingual reading datasets, powering language-specific ebook discovery features, or conducting comparative literature research across languages. Prefer it over direct Gutenberg API calls when operating within an x402 payment-enabled agentic workflow that needs a managed proxy.

## Known failure modes

- Invalid or unsupported ISO language code returns empty results or an error
- Network timeout from upstream Gutendex API
- Payment failure or insufficient USDC balance (x402 protocol)
- Malformed request body causes 400 error
- No books found for rare language codes returns count of 0 with empty list

## How this service works

List Project Gutenberg books filtered by language (ISO code, e.g. fr, de, es) and sorted by popularity via Gutendex. Returns count and matching books. Keyless. Useful for building multilingual public-domain reading datasets.

## Output

Returns a JSON object containing a total count of matching books and an array of book records filtered by the requested ISO language code, ordered by popularity, sourced from the Gutendex API (Project Gutenberg index). Each book record typically includes title, author(s), language, download count, and format links.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "properties": {}
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/suverse-gutenberg-books-by-language-36b86ef8/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from proxy.suverse.io](https://www.zero.xyz/host/proxy.suverse.io/llms.txt)