find_by_ids
Retrieve multiple MongoDB documents by their IDs in a single request for efficient queries. Preserves ID order, supports filtering fields with projection, and handles string or ObjectId identifiers.
Instructions
Find multiple documents by their IDs in a single request.
Advantages:
More efficient than multiple single document lookups
Preserves ID order in results when possible
Can filter specific fields with projection
Handles both string and ObjectId identifiers
Example: use_mcp_tool with server_name: "mongodb", tool_name: "find_by_ids", arguments: { "collection": "products", "ids": ["5f8d0f3c", "5f8d0f3d", "5f8d0f3e"], "idField": "_id", "projection": { "name": 1, "price": 1 } }
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| collection | Yes | Collection name | |
| database | No | Database name (optional if default database is configured) | |
| idField | No | Field containing the IDs (default: "_id") | |
| ids | Yes | Array of document IDs to look up | |
| projection | No | MongoDB projection to specify fields to return (optional) |
Implementation Reference
- src/index.ts:1386-1426 (handler)Handler for 'find_by_ids' tool: validates input, constructs MongoDB find query with $in on idField, applies projection if provided, retrieves documents, returns JSON.case 'find_by_ids': { const { database, collection, ids, idField = '_id', projection } = request.params.arguments as { database?: string; collection: string; ids: (string | number)[]; idField?: string; projection?: object; }; const dbName = database || this.defaultDatabase; if (!dbName) { throw new McpError( ErrorCode.InvalidRequest, 'Database name is required when no default database is configured' ); } if (!Array.isArray(ids) || ids.length === 0) { throw new McpError( ErrorCode.InvalidRequest, 'The ids parameter must be a non-empty array' ); } const db = client.db(dbName); let query = db.collection(collection).find({ [idField]: { $in: ids } }); if (projection) { query = query.project(projection); } const results = await query.toArray(); return { content: [ { type: 'text', text: JSON.stringify(results, null, 2), }, ], }; }
- src/index.ts:794-842 (registration)Registration of 'find_by_ids' tool in list_tools response, including detailed description and complete input schema definition.name: 'find_by_ids', description: `Find multiple documents by their IDs in a single request. Advantages: - More efficient than multiple single document lookups - Preserves ID order in results when possible - Can filter specific fields with projection - Handles both string and ObjectId identifiers Example: use_mcp_tool with server_name: "mongodb", tool_name: "find_by_ids", arguments: { "collection": "products", "ids": ["5f8d0f3c", "5f8d0f3d", "5f8d0f3e"], "idField": "_id", "projection": { "name": 1, "price": 1 } }`, inputSchema: { type: 'object', properties: { database: { type: 'string', description: 'Database name (optional if default database is configured)', }, collection: { type: 'string', description: 'Collection name', }, ids: { type: 'array', description: 'Array of document IDs to look up', items: { type: ['string', 'number'], }, }, idField: { type: 'string', description: 'Field containing the IDs (default: "_id")', }, projection: { type: 'object', description: 'MongoDB projection to specify fields to return (optional)', }, }, required: ['collection', 'ids'], }, },