Metabase MCP Server

Instructions

Implementation Reference

• src/server/handlers/databaseHandlers.js:120-151 (handler)

  The main handler function that executes the get_table_metadata tool: validates input, fetches table query metadata from Metabase API, processes fields, and returns formatted text content.

    async getTableMetadata(tableId) {
      Validators.validateTableId(tableId);
      
      this.logger.debug('Getting table metadata', { tableId });
      const table = await this.apiClient.makeRequest(`/api/table/${tableId}/query_metadata`);
      
      const fields = table.fields?.map(f => ({
        id: f.id,
        name: f.name,
        type: f.base_type,
        description: f.description,
      })) || [];
  
      return {
        content: [
          {
            type: 'text',
            text: `Table Metadata:
  ID: ${table.id}
  Name: ${table.name}
  Schema: ${table.schema}
  Database: ${table.db?.name}
  Total Fields: ${fields.length}
  
  Fields:
  ${fields.map(f => 
    `- ${f.name} (${f.type})${f.description ? ` - ${f.description}` : ''}`
  ).join('\n')}`,
          },
        ],
      };
    }

• src/server/config/toolDefinitions.js:143-157 (schema)

  The input schema and description definition for the get_table_metadata tool, used for validation and tool listing.

  {
    name: 'get_table_metadata',
    description: '🔍 [SAFE] Get detailed metadata for a specific table including all columns, data types, and foreign key relationships. Use this to understand table structure before writing queries. Risk: None - read-only operation.',
    inputSchema: {
      type: 'object',
      properties: {
        tableId: {
          type: 'integer',
          description: 'The ID of the table',
          minimum: 1,
        },
      },
      required: ['tableId'],
    },
  },

• src/server/MetabaseMCPServer.js:196-197 (registration)

  The switch case in executeTool that registers and dispatches calls to the getTableMetadata handler.

  case 'get_table_metadata':
    return await this.databaseHandlers.getTableMetadata(args.tableId);

• src/server/MetabaseMCPServer.js:39-39 (registration)

  Instantiation of the DatabaseHandlers class, which contains the getTableMetadata method.

  this.databaseHandlers = new DatabaseHandlers(this.apiClient);