Mcp MCP Server

@pokemontcgapi/mcp

An MCP server for the Pokémon TCG API at pokemontcgapi.com. It gives an agent eight tools over the whole catalogue: international, Japanese and Simplified Chinese print lines, card names in eight locales, illustrators, images, and prices that carry their source, basis, grade and sample size. The current counts are live at /v1/status and broken down on coverage.json.

Unofficial. Not produced, endorsed, supported by or affiliated with Nintendo, Creatures Inc., GAME FREAK inc. or The Pokémon Company International. Pokémon and all related marks are trademarks of their respective owners.

Get a key

Generate the Idempotency-Key once per signup and keep it with the request body:

IDEM=$(uuidgen)

curl -s -X POST "https://api.pokemontcgapi.com/v1/accounts/free" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $IDEM" \
  -d '{"email":"you@example.com"}'

Lost the response? Repeat the exact same request (same Idempotency-Key, same body byte for byte, same network: same public IPv4 or the same IPv6 /64) within 24 hours and the response comes back, if stored, secret included; it is the original response, so a key rotated or revoked since then is not revived. A new Idempotency-Key for the same email returns 409 ACCOUNT_EXISTS; the same key with a different body returns 409 IDEMPOTENCY_CONFLICT.

We store only a hash of the key; the signup response is kept for 24 hours so the same request can be replayed. Save data.key.secret now.

If replay is unavailable, sign in and rotate the key, or use /v1/accounts/recover with an already verified email to get a new secret.

The key comes back in data.key.secret. Confirming the address we email raises the trial from 80 to 800 credits, and the trial ends 30 days after signup. Paid plans start at 29 EUR a month: pricing.

Install

Claude Code:

claude mcp add pokemontcgapi --env PTCG_API_KEY=your-key -- npx -y @pokemontcgapi/mcp

Claude Desktop — claude_desktop_config.json:

{
  "mcpServers": {
    "pokemontcgapi": {
      "command": "npx",
      "args": ["-y", "@pokemontcgapi/mcp"],
      "env": { "PTCG_API_KEY": "your-key" }
    }
  }
}

Cursor — .cursor/mcp.json:

{
  "mcpServers": {
    "pokemontcgapi": {
      "command": "npx",
      "args": ["-y", "@pokemontcgapi/mcp"],
      "env": { "PTCG_API_KEY": "${env:PTCG_API_KEY}" }
    }
  }
}

VS Code — .vscode/mcp.json. Note the top-level key is servers, not mcpServers, and inputs keeps the key out of the committed file:

{
  "inputs": [
    { "id": "ptcg-key", "type": "promptString", "description": "pokemontcgapi key", "password": true }
  ],
  "servers": {
    "pokemontcgapi": {
      "command": "npx",
      "args": ["-y", "@pokemontcgapi/mcp"],
      "env": { "PTCG_API_KEY": "${input:ptcg-key}" }
    }
  }
}

Environment: PTCG_API_KEY, needed by seven of the eight tools, and PTCG_BASE_URL (defaults to https://api.pokemontcgapi.com). Node ≥ 20. The exception is ptcg_get_reference, which reads a public route. ptcg_get_catalogue_status is not an exception: it starts on the public /v1/status and then reads one set per print region, which needs the key. Without it the server starts and lists its tools, then those seven calls come back asking for it.

The tools

Eight tools, not one per endpoint. tools/list sits in the model's context on every turn, so the whole surface is about 11 KB, and each tool is shaped like a question rather than like a route — the model does not have to chain four calls to answer one thing.

Every tool is annotated readOnlyHint: true and destructiveHint: false. Nothing here writes. ptcg_identify_card_from_image is the one marked idempotentHint: false, because the same photo costs 25 credits every time it is sent — a client must not retry it on its own.

Commercial refusals put next_step.handoff on the first line of the tool result, followed by the API message and complete details. Show that sentence and its URL to the account owner verbatim and do not retry. The owner completes checkout, email verification or the contact step.

Importing a card catalogue

For a complete card import, use the REST API directly: GET /v1/cards?limit=250&orderBy=id, then follow links.next verbatim. The flat list fills pages across set boundaries and uses fewer requests than a separate card loop for every set. Add include=translations for names at the plain catalogue cost. Priced includes have separate tariffs. For a single print region, add q=set.region:JP or q=set.region:CN; lang only selects a name translation. Use /v1/sets/{code}/cards when you need a particular set and /v1/sets?region=JP to browse set metadata.

The quickstart contains both paging loops and dated measurements. The migration guide explains how to capture a change feed watermark before importing and maintain the replica afterwards. The MCP search tool is intended for bounded interactive searches; its region argument is sent to the API as set.region:JP (or CN, WEST), so a Japanese search reads Japanese rows only. Use REST for a complete import.

What this API does not have

The last tool exists because of this section, and it returns these facts from a live call rather than leaving a model to infer them:

• No Korean cards. Zero KR sets and zero ko translations. The print region and the locale are modelled in the schema and carry no data, so filtering on them returns an empty result, not an error.
• Card game text is English, and uneven. attacks, abilities, weaknesses, resistances, subtypes, retreat_cost, rules and flavor_text carry rows since 3 September 2026, on the 20,725 Western printings. Measured on 16 September 2026 against 57,450 cards: attacks on 29.9% of the whole catalogue and 82.9% of the Western part, subtypes 35.0%, weaknesses 28.0%, flavor_text 17.9%, abilities 7.0%, rules 5.1%. Japanese and Chinese printings carry none, so a null attacks means we do not hold it, never that the card has no attack.
• No format legalities. The card object carries no legalities field, and level is empty. If the question is about deck legality, this API cannot answer it.

All three are measured, dated in the source, and repeated verbatim in the tool descriptions, so an agent is told before it calls rather than after.

Reading prices correctly

There is no printing filter. First Edition, Unlimited, holofoil, reverse holofoil and graded rows all come back together, so read printing, condition and grading on each row rather than taking the first number. basis separates GUIDE (published upstream) from DERIVED (computed by us); PTCG_INDEX is our own composite in EUR and carries sample_n. Every observation has an as_of date and is delayed by at least a day — never quote a price without it.

What the plan withholds is named rather than hidden: graded and non_english_locales for a trial key, graded on Developer, nothing from Growth up. The API says so in meta.withheld on the prices route, in the X-Plan-Withheld header when prices ride on a card, and in a top-level withheld field on the batch. So a card with no graded rows may be the plan speaking, not the catalogue.

For ptcg_get_cards, the API's missing field is authoritative when present, including its suggested_id values. The tool keeps its existing missing array of strings and adds missing_details, an array of { id, suggested_id? }; the text also shows each suggestion. If the API omits missing, the tool falls back to comparing requested ids with returned id and legacy_id, ignoring case and repeated ids. This supports older API versions without another request, but cannot discover their unreported canonical-set collisions or suggestions. The current API omits missing when every id resolves, so that fallback then returns an empty array. ptcg_get_card_prices reads a card with its prices, so the exclusions arrive in that header.

Context discipline

Results are capped at 50 rows regardless of what the API allows, sent as aligned tables rather than JSON, with a compact field projection. A table is shorter than the same rows as JSON because the keys are not repeated on every row; we do not publish a percentage, because we have no reproducible measurement to show next to it. Truncation is always announced along with the cursor to continue. Price rows are the one thing never truncated.

Protocol

Built on @modelcontextprotocol/server v2, which negotiates the 2025-11-25 revision and accepts clients down to 2024-10-07. stdio transport.

The revision is the library's, not a claim of our own: SUPPORTED_PROTOCOL_VERSIONS in @modelcontextprotocol/server@2.0.0 tops out at 2025-11-25, so a client that asks for anything newer is answered with that. Verified against the published package, not read off a changelog.

Also available

• TypeScript SDK, zero runtime dependencies: @pokemontcgapi/sdk — source
• Docs: https://pokemontcgapi.com/docs
• Coverage, measured live: https://pokemontcgapi.com/coverage

Build from source

npm ci
npm run typecheck
npm run build

Node >= 20. npm test runs the unit tests in tests/. What CI enforces is that the package typechecks and builds on both Node 20 and Node 22, and that npm pack produces the file list the registry is meant to receive.

This package is developed inside the private monorepo that runs pokemontcgapi.com and mirrored here on each release, so a merged pull request travels back by hand rather than by merge button. That is not a reason to send patches elsewhere — open the issue or the PR here, it is the address that gets read.

Licence

MIT. Data served by the API carries per-source redistribution terms — see https://pokemontcgapi.com/legal/attribution.