MCP-MongoDB-MySQL-Server

Instructions

Implementation Reference

• src/index.ts:776-799 (handler)

  The handler function that implements the core logic of the describe_table tool. It ensures a database connection, validates the table argument, executes a MySQL DESCRIBE query, and returns the table structure as JSON.

  private async handleDescribeTable(args: any) {
    await this.ensureConnection();
  
    if (!args.table) {
      throw new McpError(ErrorCode.InvalidParams, 'Table name is required');
    }
  
    try {
      const [rows] = await this.connection!.query('DESCRIBE ??', [args.table]);
      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify(rows, null, 2),
          },
        ],
      };
    } catch (error) {
      throw new McpError(
        ErrorCode.InternalError,
        `Failed to describe table: ${getErrorMessage(error)}`
      );
    }
  }

• src/index.ts:313-322 (schema)

  Input schema defining the parameters for the describe_table tool, requiring a 'table' string.

  inputSchema: {
    type: 'object',
    properties: {
      table: {
        type: 'string',
        description: 'Table name',
      },
    },
    required: ['table'],
  },

• src/index.ts:310-323 (registration)

  Tool registration in the ListTools response, including name, description, and schema.

  {
    name: 'describe_table',
    description: 'Get table structure',
    inputSchema: {
      type: 'object',
      properties: {
        table: {
          type: 'string',
          description: 'Table name',
        },
      },
      required: ['table'],
    },
  },

• src/index.ts:545-546 (registration)

  Dispatch case in the CallToolRequestSchema handler that routes to the describe_table handler.

  case 'describe_table':
    return await this.handleDescribeTable(request.params.arguments);