tcg-mcp

A Pokemon TCG MCP server. Looks up graded cards (PSA today, CGC/BGS stubbed), manages your owned collection in a local SQLite DB, queries pricing providers (Pokemon TCG API + PriceCharting), tracks a watchlist with target prices, and snapshots PSA pop counts so you can see trends over time.

tcg-mcp is a Model Context Protocol server. Install it once, wire it into Claude Desktop / Claude Code / Cursor / any MCP client, and your assistant gains 25 tools for working with PSA cert data, your personal collection, and live market prices.

What it does — 25 tools, namespaced

PSA grading (tcg_psa_*) — cert lookup, front/back images, snapshot pop data over time, plus a workflow tool that looks up a cert and records it as owned in one call.

CGC / BGS (tcg_cgc_*, tcg_bgs_*) — stubs in v0.2; no public API exists for either grader. Listed for routing parity; will route cleanly if either grader publishes an API.

Collection (tcg_collection_*) — add raw or graded cards (or sealed products: ETBs, booster boxes, UPCs, tins), list with filters, update cost basis, soft-delete (mark sold) or hard-delete, attach a card to a pricing listing, get a cost-basis summary or a live market valuation that joins against the most recent pricing snapshots.

Pricing (tcg_pricing_*) — search a provider, get a full price quote (top-level market/low/high plus per-variant breakdown for Pokemon TCG API, plus per-grade levels for PriceCharting), persist snapshots into the local DB, bulk-snapshot every attached card in one call with per-provider rate-limit awareness, and query historical snapshots as a time series for trend analysis.

Watchlist (tcg_watchlist_*) — add target buy prices with thesis text, list by horizon (flip / hold / sealed), update, and close with a reason (bought / thesis_invalidated / manual).

Meta (tcg_list_providers) — discovery tool that shows which grading + pricing providers are enabled, what env var each needs, and what tools are in the namespace.

For the full tool list run tcg_list_providers after install or read the architecture doc.

Prerequisites

1. Python 3.10 or newer (3.13 recommended).
2. An MCP client — Claude Desktop, Claude Code, Cursor, Continue, etc.
3. (Optional, for PSA tools only) A PSA Public API token — free, sign up at psacard.com/publicapi.

The server works without any tokens — Pokemon TCG API queries, collection, and watchlist tools all function on a fresh install with zero credentials.

Install

Option A — uvx (recommended, zero install)

# install uv if you don't have it
curl -LsSf https://astral.sh/uv/install.sh | sh

# run the server (auto-installs the package on first use)
uvx tcg-mcp --help

Option B — pipx

pipx install tcg-mcp
tcg-mcp --help

Option C — pip

python3 -m pip install tcg-mcp

Option D — from source (for contributors)

git clone https://github.com/seanlok/tcg-mcp.git
cd tcg-mcp
python3 -m venv .venv
source .venv/bin/activate
pip install -e ".[dev]"
pytest        # run the test suite

Configure

Copy .env.example to .env and fill in any tokens you have:

cp .env.example .env
$EDITOR .env

Or set the env vars however your client supports it (most clients let you specify env per MCP server in the config).

Wire it into your MCP client

Claude Desktop

Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS), %APPDATA%\Claude\claude_desktop_config.json (Windows), or ~/.config/Claude/claude_desktop_config.json (Linux):

{
  "mcpServers": {
    "tcg-mcp": {
      "command": "uvx",
      "args": ["tcg-mcp"],
      "env": {
        "PSA_API_TOKEN": "your-token-here",
        "TCG_DB_PATH": "~/Documents/tcg-mcp.db"
      }
    }
  }
}

Quit Claude Desktop fully (⌘Q on macOS — closing the window isn't enough) and relaunch.

Claude Code

claude mcp add tcg-mcp -- uvx tcg-mcp

Then export the tokens you have in the shell that runs claude.

Cursor / Continue / etc.

Same shape — point the client at:

command: uvx
args:    ["tcg-mcp"]
env:     PSA_API_TOKEN=...    # optional

Smoke-test it

After wiring up the client, ask it:

"Use tcg-mcp to list providers."

You should see pokemontcg enabled, plus psa enabled if your token is set, and stubs for the others.

Then try a real lookup:

"Search Pokemon TCG API for Charizard ex from Obsidian Flames."

"Add a 1999 Pokemon Base Set Charizard #4 (raw) to my collection — paid $250 on 2026-04-15."

"Add Charizard ex Surging Sparks to my watchlist with a target buy price of $180."

"What's my collection cost basis?"

Architecture, briefly

+----------------------+
|     MCP client       |  Claude Desktop, Cursor, etc.
+----------+-----------+
           | stdio (JSON-RPC)
+----------v-----------+
|     server.py        |  FastMCP — tool registration, validation
+----------+-----------+
           |
   +-------+-------+----------------+
   |               |                |
+--v--+         +--v--+        +----v----+
| psa |  ...    |pricing|      | storage |  SQLite — collection,
+--+--+         +--+----+      +----+----+  watchlist, pop trends,
   | httpx         | httpx          |       pricing snapshots
+--v---------------v----+      +----v----+
|  PSA / Pokemon TCG    |      | tcg.db  |
|  API / PriceCharting  |      +---------+
+-----------------------+

Provider abstractions (providers/base.py, pricing/base.py) make adding a new grader or pricing source a single-file change. See docs/adding-a-provider.md.

Local SQLite database

All your personal data — collection, watchlist, pricing snapshots, pop snapshots — lives in a single SQLite file. Default location is ~/.tcg-mcp/tcg.db. Point TCG_DB_PATH at any path you prefer.

The file format is plain SQLite, so you can inspect or back up the data directly:

sqlite3 ~/.tcg-mcp/tcg.db
.tables
SELECT subject, grade, acquisition_price FROM owned_cards WHERE status='owned';

Schema is in src/tcg_mcp/storage/schema.sql. Migrations are forward-only and idempotent (safe to run on every startup).

Known limits

• PSA images only exist for cards graded after October 2021. Older slabs return an empty image list — that's the upstream API, not a bug.
• PSA's Brand field is the closest thing to a clean "set name" in their schema. We surface it as set_name; for finer-grained set parsing, reach into the raw payload.
• CGC / BGS providers are stubs in v0.2. They're listed for discovery but raise NotSupportedError if called. Implementation depends on either grader publishing a public API or an explicit decision to support polite scraping.
• Rate limits on the PSA free tier aren't publicly documented. If you see "PSA API rate limit exceeded", wait or upgrade your plan.
• PriceCharting is paid-only. Without a PRICECHARTING_TOKEN the provider is registered as disabled and graded-card prices aren't available — but Pokemon TCG API still gives you raw market prices.

Roadmap

Standing constraint: every milestone below has a free path as the default. Paid providers (GemRate, eBay Marketplace Insights, etc.) stay optional add-ons that activate only when their key is configured.

• ✅ v0.3 — shipped: tcg_pricing_snapshot_collection, tcg_pricing_get_history, rounded per-item valuation, clearer PSA 429 error message, CHANGELOG.md.
• ✅ v0.4 — shipped: Catalog tools (tcg_catalog_*) backed by Pokemon TCG API, tcg_collection_set_completion with watchlist intersection, richer tcg_collection_search, smart-routed tcg_pricing_get_card.
• v0.5 — CGC support (free path: polite scraping; optional paid GemRate).
• v0.6 — BGS support (free path: polite scraping; optional paid GemRate).
• v0.7 — eBay sold comps (free path: eBay Browse API + scraping; optional paid Marketplace Insights API).

See CHANGELOG.md for the full version history.

Contributing

Contributions welcome. To add a new grading or pricing provider, see docs/adding-a-provider.md. The contract is intentionally small: implement a Protocol method, register it conditionally based on credentials, write a mock-httpx test.

# Run tests + lint locally
pytest
ruff check .

Disclaimers

This project is independent. It is not affiliated with PSA, CGC, Beckett, The Pokemon Company, Nintendo, TCGPlayer, Cardmarket, PriceCharting, or any other organization. Each external API call is subject to that provider's Terms of Service.

License

MIT — see LICENSE.