Pokémon Battle Simulation – MCP Server

Minimal MCP server exposing:

• Pokémon data from PokeAPI
• A simple battle simulator (type effectiveness, status effects, logs)

This document explains install, run, Claude Desktop setup, and how to test.

MCP architecture (overview)

flowchart LR
  subgraph Client[Claude Desktop]
    UI[User prompt]
    MCPClient[MCP client]
  end

  subgraph Server[MCP Pokémon Server]
    Tools[Tools]
    Resources[Resources]
    Engine[BattleEngine]
    API[PokeAPI Client]
  end

  subgraph PokeAPI[PokeAPI]
    DS[(Types\nMoves\nPokémon)]
  end

  UI --> MCPClient
  MCPClient <--> |stdio JSON-RPC| Server
  Server --> Resources
  Server --> Tools
  Tools --> Engine
  Engine --> API
  Resources --> API
  API --> |HTTPS| DS

Prerequisites

• Node.js 18+ on Windows (recommended via nvm-windows or nodejs.org installer)
• Internet access (for PokeAPI and first-time dependency install)
• Claude Desktop installed

Project structure

mcp-pokemon/
├── src/
│   ├── server/            # MCP server (registers resources + tools)
│   ├── data_layer/        # PokeAPI client + caching
│   ├── battle/            # battle engine
│   └── schemas/           # TypeScript interfaces
├── scripts/
│   └── ingest_pokeapi.ts  # optional: pre-fetch data to local JSON
├── data/                  # generated by ingestion (optional)
├── dist/                  # compiled JS
├── package.json
└── tsconfig.json

1) Install

npm install

2) Build

npm run build

This compiles TypeScript to dist/.

3) Run the server (pick one)

• Development (tsx + TypeScript):

npm run dev

• Production (compiled JS):

node dist/server/index.js

Expected output: Pokémon MCP Server running on stdio.

4) Configure Claude Desktop (Windows)

Edit the file:

C:\Users\<YourUser>\AppData\Roaming\Claude\claude_desktop_config.json

Add this entry (adjust paths if needed):

{
  "mcpServers": {
    "pokemon": {
      "command": "node",
      "args": ["C:\\Users\\Sujal\\mcp-pokemon\\dist\\server\\index.js"],
      "env": {
        "NODE_ENV": "production"
      }
    }
  }
}

Notes:

• Dev alternative: "command": "npx", "args": ["tsx", "src/server/index.ts"].
• Restart Claude Desktop after editing the config.

5) Optional: Pre-fetch data

Downloads type effectiveness, popular moves, and Gen‑1 Pokémon to data/.

npm run ingest

6) Use from Claude

Example prompts:

• List the available MCP tools
• Get detailed information about Pikachu
• Search for Pokémon with “char” in the name
• Tell me about the move “thunderbolt”
• Simulate a battle between Charizard and Blastoise at level 50

Tools:

• get_pokemon(identifier: string)
• search_pokemon(query: string)
• get_move(moveName: string)
• simulate_battle(pokemon1: string, pokemon2: string, level1?: number, level2?: number)

Resource:

• pokemon://data – metadata and usage help for the Pokémon data resource

Troubleshooting

• If Claude shows “Server disconnected”, open logs: “Open Logs Folder” → mcp-server-pokemon.log.
• Ensure the config path points to the absolute dist/server/index.js.
• Rebuild after edits: npm run build.
• Manual test: node dist/server/index.js (expect stdio banner, no errors).

Uninstall / clean

# remove build output
rd /s /q dist

# remove downloaded data (if created by ingest)
rd /s /q data

License

MIT