mcp_get_container_definition

Instructions

Implementation Reference

• src/tools/containerAnalysis.ts:83-124 (handler)

  Main handler function for mcp_get_container_definition. Reads container definition (partition key, indexing policy, etag, timestamp) and throughput settings via CosmosDB SDK's container.read() and container.readOffer(). Returns ContainerInfo with throughput data.

  export const mcp_get_container_definition = async (args: { container_id: string; connection_id?: string }): Promise<ToolResult<ContainerInfo & { throughputInfo?: any }>> => {
    const { container_id, connection_id } = args;
    log(`Executing mcp_get_container_definition with: ${JSON.stringify(args)}`);
  
    try {
      const container = getContainer(container_id, connection_id);
      
      // Read container definition
      const { resource: containerDef } = await container.read();
      
      // Try to read throughput settings
      let throughputInfo;
      try {
        const offerResponse = await container.readOffer();
        throughputInfo = offerResponse.resource;
      } catch (offerError) {
        // Throughput might not be defined for shared throughput containers
        log('Could not read container throughput (might use shared database throughput)');
      }
  
      if (!containerDef) {
        throw new Error(`Container ${container_id} not found`);
      }
  
      const containerInfo: ContainerInfo & { throughputInfo?: any } = {
        id: containerDef.id,
        partitionKey: containerDef.partitionKey ? {
          paths: containerDef.partitionKey.paths || [],
          kind: containerDef.partitionKey.kind
        } : undefined,
        indexingPolicy: containerDef.indexingPolicy,
        etag: containerDef._etag,
        timestamp: containerDef._ts ? new Date(containerDef._ts * 1000) : undefined,
        throughputInfo
      };
  
      return { success: true, data: containerInfo };
    } catch (error: any) {
      log(`Error in mcp_get_container_definition for container ${container_id}: ${error.message}`);
      return { success: false, error: error.message };
    }
  };

• src/tools.ts:47-62 (schema)

  Input schema definition for mcp_get_container_definition. Declares the tool name, description, and inputSchema requiring container_id (string) and optional connection_id.

  // 3. Container Information
  {
    name: "mcp_get_container_definition",
    description: "Get detailed configuration of a specific container including partition key, indexing policy, and throughput settings. Use this to understand the container structure before writing queries. Example: mcp_get_container_definition({container_id: 'users', connection_id: 'athlete'})",
    inputSchema: {
      type: "object",
      properties: {
        container_id: {
          type: "string",
          description: "The ID/name of the container (e.g., 'users', 'orders', 'products')"
        },
        ...connectionIdProperty
      },
      required: ["container_id"]
    }
  },

• src/server.ts:126-129 (registration)

  Registration in the server's CallToolRequestHandler. Routes the 'mcp_get_container_definition' tool name to the handler function via toolHandlers.mcp_get_container_definition().

  // Container information
  case 'mcp_get_container_definition':
      result = await toolHandlers.mcp_get_container_definition(input as any);
      break;

• src/tools/index.ts:4-9 (registration)

  Re-exports mcp_get_container_definition from containerAnalysis.ts in the central tools index barrel file.

  export {
    mcp_list_databases,
    mcp_list_containers,
    mcp_get_container_definition,
    mcp_get_container_stats
  } from './containerAnalysis.js';

• src/tools/types.ts:14-24 (helper)

  ContainerInfo interface used as the shape of the returned data. Includes id, partitionKey (paths and kind), indexingPolicy, etag, and timestamp fields.

  export interface ContainerInfo {
    id: string;
    partitionKey?: {
      paths: string[];
      kind?: string;
    };
    throughput?: number;
    indexingPolicy?: any;
    etag?: string;
    timestamp?: Date;
  }