prereq API

Public JSON API for the prereq Grand Archive card database.

Base URL: https://prereq.cards/api

This documentation is also available as raw markdown at /api/docs.md, suitable for feeding to LLMs or other automated tools.

All endpoints return JSON. Errors use {"error": "..."} format. CORS is enabled for all origins.

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Authentication and usage

None. There is no authentication, no API keys, no tokens, no rate limits.

Please set a descriptive User-Agent HTTP header so we can identify your project’s requests in the logs and reach you if something goes wrong — give it a project name, URL, version number, and/or email address. Example:

User-Agent: my-deckbuilder/1.0 ([email protected])

Usage policy: Don’t be a dick. No, seriously. Don’t make me have to ban UAs or run a UA whitelist. Don’t make me have to implement real auth and a usage policy and ratelimiting.

Please think about how you’re structuring your app, and try to minimize API requests. For example, cache responses where possible. Then, consider that a few thousand extra db requests a day won’t be something I notice in the usage logs. A few billion however, and it might well be a problem. If you’re uncertain, you can get in touch and ask, email address is on the main prereq about page.

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Attribution policy

If using our API lets you provide a useful service to your users, please:

• give us credit by name and logo, and link them to http://prereq.cards

Please use the .svg on the front page as the canonical logo source. Our favicon is cropped heavily and not appropriate for most contexts.

In your own about page would be fine, or next to the feature – eg, if you have a deep-query card finder with prereq-compatible syntax, right under that could well be a good place to credit us by name, logo, and link.

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Endpoints

GET /api/version

Returns API version info.

curl https://prereq.cards/api/version

Try it →

{"version": "1", "name": "prereq"}

GET /api/status

Returns the latest set, total unique cards, and total editions (printings).

curl https://prereq.cards/api/status

Try it →

{
  "latest_set": "Mercurial Heart",
  "latest_set_code": "MRC",
  "latest_release_date": "2025-01-24",
  "total_cards": 1885,
  "total_editions": 3494
}

total_cards counts unique cards (by card_uuid). total_editions counts individual printings — the same card printed in multiple sets counts once per printing.

GET /api/search?q=…

Search for cards using the prereq query syntax.

The notable thing about this endpoint, and about prereq query syntax, is that users can type it to build complex queries in text, and for experienced users, this is fast and fluid. Consider if you’re exposing this distinct feature.

(If you’re just fetching lists of cards by their details, please use https://api.gatcg.com/cards/search instead, as documented at https://api-docs.gatcg.com/endpoints/multiple-cards – it has the advantages of being canonical, comprehensive, guranteed to be up to date etc, due to being hosted and developed by the official first-party Weebs of the Shore team.)

Parameter	Default	Description
q	(required)	Search query
page	1	Page number
page_size	50	Results per page (max 100)
sort	name	Sort field: name, rarity, cost, collector_number, set, element, type, price, winrate, date
order	asc	Sort direction: asc or desc

curl 'https://prereq.cards/api/search?q=e%3Afire+t%3Aregalia&page_size=5'

Try it →

{
  "count": 12,
  "page": 1,
  "total_pages": 3,
  "cards": [
    {
      "edition_slug": "blazing-jewel-doa-1st",
      "name": "Blazing Jewel",
      "edition_uuid": "abc123...",
      "card_uuid": "def456..."
    }
  ]
}

Response fields:

Field	Type	Description
count	integer	Total matching results across all pages
page	integer	Current page number
total_pages	integer	Total number of pages
cards	array	Array of search hits
cards[].edition_slug	string	URL-safe slug for this printing (use in /api/card/{slug})
cards[].name	string	Card name
cards[].edition_uuid	string	Unique identifier for this printing
cards[].card_uuid	string	Shared identifier across all printings of the same card

Query syntax errors return HTTP 400 with an error field describing what went wrong.

GET /api/card/

Full card data for a single printing.

curl https://prereq.cards/api/card/lorraine-wandering-warrior-doa-1st

Try it →

Response fields:

Field	Type	Description
edition_uuid	string	Unique identifier for this printing
edition_slug	string	URL-safe slug for this printing
card_uuid	string	Shared identifier across all printings of the same card
name	string	Card name
classes	string[]	Card classes, e.g. ["WARRIOR"]
types	string[]	Card types, e.g. ["CHAMPION"]
subtypes	string[]	Card subtypes, e.g. ["WARRIOR", "HUMAN"]
elements	string[]	Elements, e.g. ["FIRE"], ["WATER", "WIND"]
cost	object	Cost object (see below)
cost.type	string	"memory", "reserve", or "none"
cost.value	string?	Cost value: "0", "3", "X", or null for no cost
durability	int?	Regalia/item durability
level	int?	Champion level
life	int?	Champion life
power	int?	Attack power
speed	bool?	Whether the card is fast (true) or slow (false/null)
effect_text	string?	Card effect as plain text (for searching, display without markup)
effect_html	string?	Card effect as HTML with bolding, paragraphs, etc.
effect_reminder	string?	Reminder text only (keyword explanations), plain text
flavor_text	string?	Flavor text
illustrator	string?	Artist name
collector_number	string?	Collector number within the set
rarity	int?	Rarity: 1=Common, 2=Uncommon, 3=Rare, 4=Super Rare, 5=Ultra Rare, 6=Promo Rare, 7=CSR, 8=CUR, 9=CPR
set_code	string?	Set code, e.g. "DOA-1ST"
set_name	string?	Set name, e.g. "Dawn of Ashes First Edition"
images	object	Image URLs (see Card images section)
images.index_jpg	string?	500x700 JPG from the official GA Index
images.avif	string?	300px-wide AVIF from prereq CDN
images.thumbnail	string?	180px-wide AVIF thumbnail, cropped to card top
is_flip_card	bool	Whether this card has a back face
back_name	string?	Back face name (flip cards only)
back_classes	string[]	Back face classes
back_types	string[]	Back face types
back_subtypes	string[]	Back face subtypes
back_elements	string[]	Back face elements
back_cost	object	Back face cost (same structure as cost)
back_durability	int?	Back face durability
back_level	int?	Back face level
back_life	int?	Back face life
back_power	int?	Back face power
back_speed	bool?	Back face speed
back_effect_text	string?	Back face effect as plain text
back_effect_html	string?	Back face effect as HTML
back_effect_reminder	string?	Back face reminder text
back_flavor_text	string?	Back face flavor text
back_illustrator	string?	Back face illustrator
back_images	object?	Back face image URLs (same structure as images; null if not a flip card)
release_date	string?	Release date
language	string?	Language code, e.g. "EN"

The cost object matches the official GA API format. A card has at most one cost type — memory or reserve, never both. Examples:

• Memory cost 3: {"type": "memory", "value": "3"}
• Reserve cost X: {"type": "reserve", "value": "X"}
• No cost (champions, etc.): {"type": "none", "value": null}

Returns 404 if the edition slug doesn’t match any card.

GET /api/card/{edition_slug}/offers

Price offers for a card from tracked stores.

Parameter	Default	Description
region	(all)	Filter by region: NZ, AU, or GLOBAL

curl https://prereq.cards/api/card/lorraine-wandering-warrior-doa-1st/offers
curl 'https://prereq.cards/api/card/lorraine-wandering-warrior-doa-1st/offers?region=NZ'

Try it →

{
  "edition_slug": "lorraine-wandering-warrior-doa-1st",
  "offers": [
    {
      "store_name": "Card Merchant Hamilton",
      "store_slug": "cm-hamilton",
      "region_code": "NZ",
      "price_cents": 50,
      "currency": "NZD",
      "condition": "NM",
      "finish": "normal",
      "quantity": 4,
      "product_url": "https://cardmerchanthamilton.co.nz/...",
      "scraped_at": "2026-02-26T08:00:00+00:00"
    }
  ]
}

Response fields:

Field	Type	Description
edition_slug	string	The card’s edition slug
offers	array	Array of price offers, sorted by price ascending
offers[].store_name	string	Store display name
offers[].store_slug	string	Store identifier
offers[].region_code	string	"NZ", "AU", or "GLOBAL"
offers[].price_cents	integer	Price in minor currency units (cents)
offers[].currency	string	Currency code, e.g. "NZD", "AUD"
offers[].condition	string?	Card condition, e.g. "NM"
offers[].finish	string?	Card finish, e.g. "normal", "foil"
offers[].quantity	int?	Available quantity (null if unknown)
offers[].product_url	string?	Direct link to the store listing
offers[].scraped_at	string?	ISO 8601 timestamp of when this offer was last confirmed — updates every scrape even if the price hasn’t changed

Returns 404 if the card doesn’t exist. An empty offers array means the card exists but has no tracked offers.

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Card images

There are three image sources available.

Index JPGs (official GA API)

The images.index_jpg field points to the official 500x700 JPG hosted by the GA Index. These are the canonical card images, suitable for most use cases. They’re the highest publically available quality, and widely compatible. They’re basically guranteed to be available so long as the cards are up on the Index. For further documentation, see the docs at https://api-docs.gatcg.com/endpoints/images which will tell you how to hit up the https://api.gatcg.com/cards/images/{filename} endpoint.

https://api.gatcg.com/cards/images/{edition_uuid}.jpg

prereq CDN — AVIF (fast, compact)

The images.avif field points to 300px-wide AVIF images on prereq’s CDN (Cloudflare R2). These are re-encoded from the originals for fast loading in modern browsers, and served from a Cloudflare CDN. If you want your app to go fast, are serving modern browsers, and can trade off some quality, these may be appropriate, and are what prereq uses. Note that they may not be available immediately when new cards are added, as the image processing happens offline on my laptop whenever I notice that there’s new cards.

https://cdn.prereq.cards/{set_code}/{filename}.avif

prereq CDN — Thumbnails (tiny)

The images.thumbnail field points to 180px-wide AVIF thumbnails. These are heavily compressed, and cropped to approximately the top 1/7th of the card (showing the name, element, cost, and top of the illustration). They can get down to low single-digit kilobytes per image, which saves bandwidth and loading time when showing a lot of card images at once. Same benefits and caveats as the large prereq images apply.

https://cdn.prereq.cards/{set_code}/{filename}-s.avif

Hotlinking

prereq’s image CDN runs on Cloudflare R2, which has no egress fees. Hotlinking cdn.prereq.cards images costs us nothing, and we do not consider this use of our API. So you don’t need to credit us for this usecase, and as for usage amount, Cloudflare can handle any traffic you can generate.

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Query syntax

The q parameter accepts the full prereq query language. See /help for the complete reference.

Examples, drawn from the help page:

• silvie — name searches
• e:fire t:regalia — fire element regalias
• e:luxem fx:"class bonus" t:tamer — luxem cards with class-bonus tamer effects
• !e:a pow>5 — non-advanced element cards with power above 5
• fx:"deal ? damage" — cards dealing damage (single-character wildcard)
• c:3 — cards costing exactly 3 memory or reserve
• e:water OR e:norm t:aethercharge — water or norm element aethercharges
• i:Taki — cards illustrated by Taki