mcp_list_databases

Instructions

Implementation Reference

• src/tools/containerAnalysis.ts:12-49 (handler)

  The main handler function that executes the mcp_list_databases tool logic. It accepts an optional connection_id, retrieves the CosmosDB client, lists all databases via client.databases.readAll().fetchAll(), and returns database info (id, etag, timestamp) along with connection metadata.

  export const mcp_list_databases = async (args?: { connection_id?: string }): Promise<ToolResult<any>> => {
    const connection_id = args?.connection_id;
    log(`Executing mcp_list_databases with connection_id: ${connection_id || 'default'}`);
  
    try {
      const connInfo = getConnectionInfo(connection_id);
      log(`[DEBUG] Connection info: ${JSON.stringify(connInfo)}`);
      
      const database = getDatabase(connection_id);
      const client = database.client;
      
      const { resources: databases } = await client.databases.readAll().fetchAll();
      
      const databasesInfo = databases.map(db => ({
        id: db.id,
        etag: db._etag,
        timestamp: new Date(db._ts * 1000)
      }));
  
      // Include connection info for clarity
      return { 
        success: true, 
        data: {
          connection: {
            id: connInfo.connectionId,
            endpoint: connInfo.endpoint,
            databaseId: connInfo.databaseId,
            allowModifications: connInfo.allowModifications
          },
          availableConnections: connInfo.registeredConnections,
          databases: databasesInfo
        }
      };
    } catch (error: any) {
      log(`Error in mcp_list_databases: ${error.message}`);
      return { success: false, error: error.message };
    }
  };

• src/tools.ts:22-32 (schema)

  Schema/registration definition for the mcp_list_databases tool. Defines the tool name, description, and input schema (optional connection_id property).

  {
    name: "mcp_list_databases",
    description: "List all databases in the CosmosDB account. Use this to discover available databases before querying containers. Returns database IDs, timestamps, and ETags.",
    inputSchema: {
      type: "object",
      properties: {
        ...connectionIdProperty
      },
      required: []
    }
  },

• src/server.ts:119-121 (registration)

  Registration entry in the MCP CallTool handler's switch statement. Routes the tool name 'mcp_list_databases' to the handler function imported from './mcp-server.js'.

  case 'mcp_list_databases':
      result = await toolHandlers.mcp_list_databases(input as any);
      break;

• src/db.ts:305-307 (helper)

  Helper function getDatabase() used by the handler to retrieve the CosmosDB Database reference for the specified connection.

  export const getDatabase = (connectionId?: string): Database => {
    return getConnection(connectionId).database;
  };

• src/db.ts:320-344 (helper)

  Helper function getConnectionInfo() used by the handler to retrieve connection metadata for inclusion in the response.

  export const getConnectionInfo = (connectionId?: string): { 
    connectionId: string;
    endpoint: string; 
    databaseId: string; 
    allowModifications: boolean;
    pid: number;
    activeConnections: string[];
    registeredConnections: string[];
  } => {
    const id = resolveConnectionId(connectionId);
    const connection = activeConnections.get(id);
    const config = registeredConnections.get(id);
    
    const { endpoint } = config ? parseConnectionString(config.connectionString) : { endpoint: 'NOT CONNECTED' };
    
    return {
      connectionId: id,
      endpoint,
      databaseId: config?.databaseId || 'NOT SET',
      allowModifications: config?.allowModifications || false,
      pid: process.pid,
      activeConnections: Array.from(activeConnections.keys()),
      registeredConnections: Array.from(registeredConnections.keys())
    };
  };