memento-mcp

Instructions

Implementation Reference

• src/server/handlers/listToolsHandler.ts:258-308 (registration)

  Registration of the 'update_relation' tool including its name, description, and input schema

  {
    name: 'update_relation',
    description:
      'Update an existing relation with enhanced properties in your Memento MCP knowledge graph memory',
    inputSchema: {
      type: 'object',
      properties: {
        relation: {
          type: 'object',
          properties: {
            from: {
              type: 'string',
              description: 'The name of the entity where the relation starts',
            },
            to: {
              type: 'string',
              description: 'The name of the entity where the relation ends',
            },
            relationType: {
              type: 'string',
              description: 'The type of the relation',
            },
            strength: {
              type: 'number',
              description: 'Optional strength of relation (0.0 to 1.0)',
            },
            confidence: {
              type: 'number',
              description: 'Optional confidence level in relation accuracy (0.0 to 1.0)',
            },
            metadata: {
              type: 'object',
              description:
                'Optional metadata about the relation (source, timestamps, tags, etc.)',
              additionalProperties: true,
            },
            // Temporal fields - optional
            id: { type: 'string', description: 'Optional relation ID' },
            version: { type: 'number', description: 'Optional relation version' },
            createdAt: { type: 'number', description: 'Optional creation timestamp' },
            updatedAt: { type: 'number', description: 'Optional update timestamp' },
            validFrom: { type: 'number', description: 'Optional validity start timestamp' },
            validTo: { type: 'number', description: 'Optional validity end timestamp' },
            changedBy: { type: 'string', description: 'Optional user/system identifier' },
          },
          required: ['from', 'to', 'relationType'],
        },
      },
      required: ['relation'],
    },
  },

• src/server/handlers/callToolHandler.ts:79-81 (handler)

  Handler logic for executing the 'update_relation' tool by delegating to KnowledgeGraphManager.updateRelation

  case 'update_relation':
    await knowledgeGraphManager.updateRelation(args.relation);
    return { content: [{ type: 'text', text: 'Relation updated successfully' }] };

• src/KnowledgeGraphManager.ts:1064-1093 (helper)

  Core updateRelation method in KnowledgeGraphManager that delegates to storage provider or uses file-based fallback

  async updateRelation(relation: Relation): Promise<Relation> {
    if (this.storageProvider && hasUpdateRelation(this.storageProvider)) {
      // Cast to the extended interface to access the method
      const provider = this.storageProvider as unknown as StorageProviderWithUpdateRelation;
      return provider.updateRelation(relation);
    }
  
    // Fallback implementation
    const graph = await this.loadGraph();
  
    // Find the relation to update
    const index = graph.relations.findIndex(
      (r) =>
        r.from === relation.from && r.to === relation.to && r.relationType === relation.relationType
    );
  
    if (index === -1) {
      throw new Error(
        `Relation from '${relation.from}' to '${relation.to}' of type '${relation.relationType}' not found`
      );
    }
  
    // Update the relation
    graph.relations[index] = relation;
  
    // Save the updated graph
    await this.saveGraph(graph);
  
    return relation;
  }