# Polyglot Publishing

> An independent publisher of public-domain literature in bilingual editions. Every book in the
> catalogue is produced on demand in any ordered pair of 44 languages —
> the language the reader is learning paired with the language they already know — as an ebook
> (PDF/EPUB) or a print-on-demand paperback. 276 titles, so 522,192
> buyable editions, none of which exists until someone orders it.

## Buying from an AI assistant

This site supports agentic commerce. An assistant can search the catalogue, price an edition and
open a payment link without a human touching the website first.

- MCP server (Streamable HTTP, no authentication): `https://www.polyglot-publishing.com/api/mcp`
  - `search_books` — Search the catalogue
  - `get_book` — Get one book
  - `get_excerpt` — Read an excerpt
  - `list_languages` — List the languages
  - `list_editions` — List the buyable editions
  - `create_checkout_link` — Create a payment link
- Product feed (JSON and TSV): `https://www.polyglot-publishing.com/api/agent/feed`
- Machine-readable catalogue of one book: `https://www.polyglot-publishing.com/api/agent/feed?book_uid=<uid>`
- A real excerpt of an edition, as text — each segment in the learning language with its
  translation just below: `https://www.polyglot-publishing.com/api/agent/excerpt?book_uid=<uid>&learn=<code>&reader=<code>`
  (JSON, or `&format=text`). 263 titles have one; the same text is on
  their product pages.

Payment always ends with a human: `create_checkout_link` returns a Stripe payment link that the
buyer opens themselves. Nothing is charged before that, and the link expires after 24 hours.
For merchants and platforms implementing the Agentic Commerce Protocol, the checkout endpoints
live under `https://www.polyglot-publishing.com/api/acp/checkout_sessions` and require an API key.

## How an edition is described

An edition is identified by `book_uid:learning_language:known_language:layout:channel`, plus a
third language for trilingual editions. Always reuse an `item_id` returned by the API rather
than assembling one: not every combination can be produced, and `list_editions` is what tells
you which can.

## Languages

English (en), French (fr), Spanish (es), German (de), Italian (it), Russian (ru), Arabic (ar), Bulgarian (bg), Bengali (bn), Catalan (ca), Czech (cs), Danish (da), Greek (el), Esperanto (eo), Estonian (et), Persian (fa), Finnish (fi), Hebrew (he), Hindi (hi), Croatian (hr), Hungarian (hu), Indonesian (id), Japanese (ja), Kazakh (kk), Korean (ko), Lithuanian (lt), Latvian (lv), Dutch (nl), Norwegian (no), Polish (pl), Portuguese (pt), Brazilian Portuguese (pt_br), Romanian (ro), Serbian (Latin) (sr), Serbian (Cyrillic) (sr_cyrl), Slovak (sk), Slovenian (sl), Swedish (sv), Swahili (sw), Turkish (tr), Ukrainian (uk), Vietnamese (vi), Chinese (Simplified) (zh), Chinese (Traditional) (zh_tw)

## Catalogue

- [Catalogue](https://www.polyglot-publishing.com/en/catalogue): all titles, browsable in 44 interface languages
- [Answers for assistants](https://www.polyglot-publishing.com/llms-full.txt): levels, formats, prices, every title and how to link to one pair
- [Sitemap index](https://www.polyglot-publishing.com/sitemap.xml): every book in every language pair
- [Learning a language by reading](https://www.polyglot-publishing.com/en/resources/learn-a-language-by-reading): why
  reading works, the reading methods (graded readers, parallel texts, line-by-line, interlinear,
  audio) with their limits, and every layout of our books — in 44 languages
  under `/<code>/resources/learn-a-language-by-reading`
- [Resources](https://www.polyglot-publishing.com/en/resources): best bilingual books per language to learn, authors by
  country, what to read next, books adapted for the screen
- [About](https://www.polyglot-publishing.com/en/about): who publishes these books
- [FAQ](https://www.polyglot-publishing.com/en/faq): formats, delivery, refunds

## Terms

- [Terms of sale](https://www.polyglot-publishing.com/en/sales-policy)
- [Privacy policy](https://www.polyglot-publishing.com/en/privacy)
- [Legal notice](https://www.polyglot-publishing.com/en/mentions-legales)

## Notes

- Prices are always given in euros; when another currency is requested, Stripe charges the
  converted amount in that currency. The charged amount is always resolved server-side at
  checkout, never taken from the caller.
- Ebooks are generated for the exact language pair ordered. The download link is sent by email as
  soon as the book is ready, within 48 hours at the latest; otherwise the order is refunded
  automatically.
- Paperbacks are printed on demand and need a shipping address, so they cannot be bought through
  a bare payment link — send the buyer to the product page.