open_nodes
Extract specific entities from a knowledge graph by providing their names, enabling targeted retrieval for LLM memory operations on the MCP Memory Server.
Instructions
Open specific nodes in the knowledge graph by their names
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| names | Yes | An array of entity names to retrieve |
Implementation Reference
- src/index.ts:163-183 (handler)The openNodes method in the KnowledgeGraphManager class implements the core logic for the 'open_nodes' tool. It loads the full graph, filters entities by the provided names, includes only relations between those entities, and returns the resulting subgraph.
async openNodes(names: string[]): Promise<KnowledgeGraph> { const graph = await this.loadGraph(); // Filter entities const filteredEntities = graph.entities.filter(e => names.includes(e.name)); // Create a Set of filtered entity names for quick lookup const filteredEntityNames = new Set(filteredEntities.map(e => e.name)); // Filter relations to only include those between filtered entities const filteredRelations = graph.relations.filter(r => filteredEntityNames.has(r.from) && filteredEntityNames.has(r.to) ); const filteredGraph: KnowledgeGraph = { entities: filteredEntities, relations: filteredRelations, }; return filteredGraph; } - src/index.ts:360-370 (schema)Input schema definition for the 'open_nodes' tool, specifying that it takes an object with a required 'names' property that is an array of strings.
inputSchema: { type: "object", properties: { names: { type: "array", items: { type: "string" }, description: "An array of entity names to retrieve", }, }, required: ["names"], }, - src/index.ts:357-371 (registration)Registration of the 'open_nodes' tool in the ListToolsRequestSchema response. Includes the tool name, description, and input schema.
{ name: "open_nodes", description: "Open specific nodes in the knowledge graph by their names", inputSchema: { type: "object", properties: { names: { type: "array", items: { type: "string" }, description: "An array of entity names to retrieve", }, }, required: ["names"], }, }, - src/index.ts:403-404 (handler)Dispatch handler in the CallToolRequestSchema that invokes the openNodes method with the provided arguments and formats the response as JSON.
case "open_nodes": return { content: [{ type: "text", text: JSON.stringify(await knowledgeGraphManager.openNodes(args.names as string[]), null, 2) }] };