Batch cards

Comma-separated ids, at most 100; a 101st is LIMIT_EXCEEDED. A canonical set code binds the lookup to that set, using the longest matching code and preserving the full number, including zeros. Historical aliases resolve only when their prefix is not a canonical set code.

Comma-separated card fields to return. id is always included. camelCase and snake_case both resolve, so nationalPokedexNumbers works and comes back as national_pokedex_numbers. An unknown name is INVALID_SELECT_FIELD, with the full list in details.valid_fields.

Comma-separated includes: index, prices, translations, images, set, artist. include=index exposes index_eur and last_price_at at 1 credit per 50 requested ids. Selecting those fields without index or prices leaves them out and reports top-level withheld: ["index"]. include=prices includes the index and plan-filtered quotes at 4 credits per 25 requested ids; top-level withheld names price restrictions and is absent when none apply. legalities is rejected with 400 INVALID_INCLUDE.

Locale for the card name: en, fr, de, ja, it, es, pt, zh — the eight with translation rows in the catalogue. A card with no translation in the requested locale falls back to English rather than to null.

Send back the ETag you stored. The API returns a strong ETag on every catalogue response, and a 304 is a header exchange: no body, no database row read.