tokyo-metro-mcp-server/mastra-integration.md

MCP server for Tokyo Metro API integration

# Tokyo Metro MCP Server - Mastra Integration

## Option 1: Direct Node Execution (Recommended)

Use absolute paths since `cwd` is not supported:

```typescript
import { MCPClient } from "@mastra/mcp";

const mcp = new MCPClient({
  servers: {
    postgres: {
      command: "npx",
      args: [
        "-y",
        "@modelcontextprotocol/server-postgres",
        "postgres://postgres:postgres@localhost:5432/employee",
      ],
    },
    tokyoMetro: {
      command: "node",
      args: ["/home/ta/tokyo-metro/dist/index.js"],
      env: {
        MODE: "stdio",
      },
    },
  },
});
```

## Option 2: Global Installation

First install the server globally and add bin script:

Add to package.json:
```json
{
  "bin": {
    "tokyo-metro-mcp": "./dist/index.js"
  }
}
```

Then:
```bash
cd /home/ta/tokyo-metro
npm run build
npm link
```

Use in Mastra:
```typescript
const mcp = new MCPClient({
  servers: {
    tokyoMetro: {
      command: "tokyo-metro-mcp",
      args: [],
    },
  },
});
```

## Option 3: NPX with GitHub

Publish to npm or use npx with absolute path:

```typescript
const mcp = new MCPClient({
  servers: {
    tokyoMetro: {
      command: "npx",
      args: ["-y", "/home/ta/tokyo-metro"],
    },
  },
});
```

## Usage Example

```typescript
import { MCPClient } from "@mastra/mcp";
import { Agent } from "@mastra/core/agent";
import { openai } from "@ai-sdk/openai";

const mcp = new MCPClient({
  servers: {
    tokyoMetro: {
      command: "npm",
      args: ["start"],
      cwd: "/home/ta/tokyo-metro",
      env: { MODE: "stdio" },
    },
  },
});

const agent = new Agent({
  name: "Tokyo Metro Assistant",
  instructions: "You can access Tokyo Metro data including COVID-19 statistics and general API queries.",
  model: openai("gpt-4"),
  tools: await mcp.getTools(),
});

// Test the integration
const response = await agent.generate(
  "Get COVID-19 data for Tokyo from January 2021 to March 2021"
);

console.log(response.text);
```

## Available Tools

Once integrated, you'll have access to these tools:

- `tokyoMetro_tokyo_metro_query` - Query any Tokyo Metro API endpoint
- `tokyoMetro_get_sample_covid_data` - Get COVID-19 data with date filtering

The subprocess approach is more reliable than HTTP/SSE for MCP integration with Mastra.