mcp-mysql-lens

Instructions

Implementation Reference

• src/index.ts:171-194 (handler)

  The handler function for the 'describe_table' tool. Extracts 'database' (optional) and 'table' (required) parameters, executes a DESCRIBE query via the executeQuery helper, and returns the table schema as JSON-formatted rows.

  case "describe_table": {
    console.error('[Tool] Executing describe_table');
    
    const database = request.params.arguments?.database as string | undefined;
    const table = request.params.arguments?.table as string;
    
    if (!table) {
      throw new McpError(ErrorCode.InvalidParams, "Table name is required");
    }
    
    const { rows } = await executeQuery(
      pool,
      `DESCRIBE \`${table}\``,
      [],
      database
    );
    
    return {
      content: [{
        type: "text",
        text: JSON.stringify(rows, null, 2)
      }]
    };
  }

• src/index.ts:89-106 (registration)

  Registration of the 'describe_table' tool within the ListToolsRequestSchema handler. Includes the tool's name, description, and input schema definition.

  {
    name: "describe_table",
    description: "Show the schema for a specific table",
    inputSchema: {
      type: "object",
      properties: {
        database: {
          type: "string",
          description: "Database name (optional, uses default if not specified)"
        },
        table: {
          type: "string",
          description: "Table name"
        }
      },
      required: ["table"]
    }
  },