MCP ArkhamDB Server

An MCP (Model Context Protocol) server for interacting with the ArkhamDB public API. This server provides tools to query cards and decks from Arkham Horror: The Card Game.

Features

• Get Card: Retrieve details of a specific card by its code
• Search Cards by Name: Search for cards by name (case-insensitive partial match)
• Find Card Synergies: Discover cards that synergize with a given card based on text analysis, trait matching, and mechanic keywords
• Get Deck: Retrieve a deck by its ID (may require authentication)
• Get Decklist: Retrieve a decklist by its ID
• Suggest Deck Improvements: Suggest cards that would improve a deck, considering investigator requirements (deck size, class restrictions, level, experience)

Example of promts using the MCP server

In Spanish

Utiliza el mcp de arkhamdb para bajar información sobre el siguiente mazo: 5570650

Quiero que analices todas sus cartas, sus sinergias, y me expliques sus puntos fuertes y sus debilidades, y cómo utilizarlo y jugar este mazo, incluyendo información sobre qué mulligan debería hacer. Puedes buscar en internet información sobre Arkham Horror LCG. Los nombres de las cartas y la explicación han de estar en español.

Result: examples/darrell-spanish.md

Sugiéreme mejoras para este mazo 5570650 usando el mcp de arkhamdb, recuerda poner los nombres de las cartas en español, recuerda que el mazo no puede tener más de 30 cartas (sin contar las propias de darrell), por lo que no se puede añadir cartas y ya está, hay que quitar otras. Hay muchas más cartas en el mazo, intenta enfocarte en cartas que aprovechen sinergias con "evidence", con añadir pruebas y usar pruebas con la habilidad de darrell, y también con cartas para descubrir más pistas

Result: examples/darrell-mejoras.md

Usa el MCP de arkhamdb para encontrar sinergias para Darrell Simmons, que usa `evidence`, recuerda usar el nombre español de las cartas

Result: examples/darrell-sinergias.md

Ayúdame a montar un mazo de Trish Scarborough para jugar la campaña de Innsmouth. Puedes buscar información sobre mazos en internet y usar las herramientas del MCP de arkhamdb. He visto dos posibles mazos iniciales, aunque no me gusta lo de empezar con "En la brecha". https://es.arkhamdb.com/deck/view/2635733 https://es.arkhamdb.com/decklist/view/26638/trish-scarborough-starter-deck-1.0

Result (after some iterations): examples/trish-scarborough-deck.md

In English

Use the arkhamdb mcp to get information about the following deck: 5570650

I want you to analyze all its cards, its synergies, and explain its strengths and weaknesses, and how to use it and play this deck, including information about what mulligan should be made. You can search the internet for information about Arkham Horror LCG.

Result: examples/darrell-english.md

Installation

1. Clone this repository
2. Install dependencies:

make dependencies

Or manually:

go mod download

1. Build the server:

make build

Or manually:

go build -o arkhamdb-mcp

Running with Docker

1. Build and start the server:

docker-compose up --build

1. The server will listen on stdin/stdout using the MCP protocol.

For Cursor integration, you can use the run-docker-mcp.sh script:

{
  "mcpServers": {
    "arkhamdb": {
      "command": "<path-to>/arkhamdb-mcp/run-docker-mcp.sh",
      "args": []
    }
  }
}

Usage

The server communicates via stdin/stdout using the MCP protocol. It connects to the ArkhamDB API at https://es.arkhamdb.com.

Testing

Use the provided test script:

./test-mcp.sh

Or test manually using JSON-RPC over stdin:

Initialize the server:

echo '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test-client","version":"1.0.0"}}}' | ./arkhamdb-mcp

List available tools:

echo -e '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test-client","version":"1.0.0"}}}\n{"jsonrpc":"2.0","id":2,"method":"tools/list"}' | ./arkhamdb-mcp

Get a card:

echo -e '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test-client","version":"1.0.0"}}}\n{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"arkhamdb_get_card","arguments":{"cardCode":"01001"}}}' | ./arkhamdb-mcp

Search cards by name:

echo -e '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test-client","version":"1.0.0"}}}\n{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"arkhamdb_search_cards_by_name","arguments":{"name":"Roland"}}}' | ./arkhamdb-mcp

Get a deck:

echo -e '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test-client","version":"1.0.0"}}}\n{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"arkhamdb_get_deck","arguments":{"deckID":12345}}}' | ./arkhamdb-mcp

Find card synergies:

echo -e '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test-client","version":"1.0.0"}}}\n{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"arkhamdb_find_card_synergies","arguments":{"cardCode":"06332","maxResults":10}}}' | ./arkhamdb-mcp

The synergy finder analyzes cards using multiple methods:

• Trait References: Finds cards that match explicit trait references (e.g., [[Item]], [[Spell]])
• Shared Traits: Identifies cards with matching traits
• Mechanic Keywords: Detects cards that interact with similar game mechanics (investigation, damage, resources, etc.)
• Slot Compatibility: Considers equipment slot compatibility

Suggest deck improvements:

echo -e '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test-client","version":"1.0.0"}}}\n{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"arkhamdb_suggest_deck_improvements","arguments":{"decklistID":5570650,"maxResults":20}}}' | ./arkhamdb-mcp

The deck improvement tool analyzes a deck and suggests cards that would improve it:

• Investigator Requirements: Respects deck size, class restrictions (faction), level limits, and experience requirements
• Synergy Analysis: Scores cards based on synergies with existing deck cards
• Deck Compatibility: Only suggests cards that are legal for the investigator
• Prioritization: Favors low-cost and level 0 cards for easier inclusion

Integration with AI Models

This MCP server can be integrated with:

• Cursor
• Claude Desktop
• ChatGPT with MCP support
• Any MCP-compatible AI client

Configure your AI client to connect to this server using the MCP protocol over stdio. For Cursor, add to your mcp.json:

{
  "mcpServers": {
    "arkhamdb": {
      "command": "<path-to>/arkhamdb-mcp/arkhamdb-mcp",
      "args": []
    }
  }
}

API Reference

The server uses the public ArkhamDB API endpoints:

• GET /api/public/card/{card_code}.json - Get a single card
• GET /api/public/cards/ - Get all cards (used for searching by name and synergy detection)
• GET /api/public/deck/{deck_id}.json - Get a deck (may require authentication)
• GET /api/public/decklist/{decklist_id}.json - Get a decklist

The synergy finder tool (arkhamdb_find_card_synergies) uses the cards endpoint to analyze all cards and identify synergies through text parsing and trait matching.

For more information, see the ArkhamDB API documentation.

Development

Code Quality

• Lint: Run make lint to check code quality
• Format: Run make format to format code
• Inspect: Run make inspect to inspect MCP protocol compliance

Makefile Targets

• make dependencies - Install all dependencies
• make lint - Run linter
• make format - Format code
• make inspect - Inspect MCP protocol compliance
• make build - Build Docker image

Architecture

The server follows a modular architecture:

• main.go - Entry point and initialization
• server/ - MCP protocol implementation
• tools/ - Tool interface definitions
• arkhamdb/ - ArkhamDB API client implementation
  • arkhamdb.go - API client and card/deck fetching
  • synergy.go - Synergy detection logic (text parsing, trait matching, scoring)

License

MIT License