feat(memory): add read_graph_summary function for efficient entity overview

src/memory/README.md

@@ -108,6 +108,18 @@ Example:
   - No input required
   - Returns complete graph structure with all entities and relations
 
+- **read_graph_summary**
+  - Read a summary of the knowledge graph which includes a summary of each entity and all relations.
+  - No input required
+  - Returns:
+    - Entity summaries with:
+      - `name` (string): Entity name
+      - `entityType` (string): Entity type
+      - `observationCount` (number): Total number of observations
+      - `lastObservation` (string, optional): The most recent observation for the entity
+    - Complete relations array (unchanged from full graph)
+  - Use this to get an overview of the entire graph, then use `open_nodes` to get full details for specific entities
+
 - **search_nodes**
   - Search for nodes based on query
   - Input: `query` (string)

src/memory/index.ts

@@ -38,6 +38,18 @@ interface KnowledgeGraph {
   relations: Relation[];
 }
 
+interface EntitySummary {
+  name: string;
+  entityType: string;
+  observationCount: number;
+  lastObservation?: string;
+}
+
+interface KnowledgeGraphSummary {
+  entities: EntitySummary[];
+  relations: Relation[];
+}
+
 // The KnowledgeGraphManager class contains all operations to interact with the knowledge graph
 class KnowledgeGraphManager {
   private async loadGraph(): Promise<KnowledgeGraph> {
@@ -143,6 +155,32 @@ class KnowledgeGraphManager {
     return this.loadGraph();
   }
 
+  async readGraphSummary(): Promise<KnowledgeGraphSummary> {
+    const graph = await this.loadGraph();
+
+    // Create entity summaries without full observation arrays
+    const entitySummaries = graph.entities.map(entity => {
+      const observationCount = entity.observations.length;
+      let lastObservation: string | undefined;
+
+      if (observationCount > 0) {
+        lastObservation = entity.observations[observationCount - 1];
+      }
+
+      return {
+        name: entity.name,
+        entityType: entity.entityType,
+        observationCount,
+        lastObservation
+      };
+    });
+
+    return {
+      entities: entitySummaries,
+      relations: graph.relations // Relations are already lightweight, include them all
+    };
+  }
+
   // Very basic search function
   async searchNodes(query: string): Promise<KnowledgeGraph> {
     const graph = await this.loadGraph();
@@ -365,6 +403,15 @@ server.setRequestHandler(ListToolsRequestSchema, async () => {
           additionalProperties: false,
         },
       },
+      {
+        name: "read_graph_summary",
+        description: "Read the knowledge graph summary. Returns all entity names, types, observation counts, and most recent observations without loading full observation arrays. Use open_nodes to get complete details for specific entities.",
+        inputSchema: {
+          type: "object",
+          properties: {},
+          additionalProperties: false,
+        },
+      },
       {
         name: "search_nodes",
         description: "Search for nodes in the knowledge graph based on a query",
@@ -404,6 +451,10 @@ server.setRequestHandler(CallToolRequestSchema, async (request) => {
     return { content: [{ type: "text", text: JSON.stringify(await knowledgeGraphManager.readGraph(), null, 2) }] };
   }
 
+  if (name === "read_graph_summary") {
+    return { content: [{ type: "text", text: JSON.stringify(await knowledgeGraphManager.readGraphSummary(), null, 2) }] };
+  }
+
   if (!args) {
     throw new Error(`No arguments provided for tool: ${name}`);
   }