Elasticsearch Knowledge Graph for MCP

Instructions

Implementation Reference

• src/index.ts:857-898 (handler)

  MCP tool handler for delete_entities: validates input parameters (names array and memory_zone), loops through each entity name, calls kgClient.deleteEntity with cascadeRelations option, collects results including success/failure and errors, returns formatted response.
  else if (toolName === "delete_entities") { const names = params.names; const zone = params.memory_zone; const cascadeRelations = params.cascade_relations !== false; // Default to true const results = []; const invalidNames = []; // Validate names before attempting deletion for (const name of names) { if (!name || name.trim() === '') { invalidNames.push("[empty]"); continue; } } // If there are invalid names, reject those operations if (invalidNames.length > 0) { return formatResponse({ success: false, error: "Entity deletion failed for some entities", invalidNames, message: "Entity names cannot be empty" }); } // Delete each valid entity individually for (const name of names) { try { const success = await kgClient.deleteEntity(name, zone, { cascadeRelations }); results.push({ name, deleted: success }); } catch (error) { results.push({ name, deleted: false, error: error.message }); } } return formatResponse({ success: true, results }); }
• src/index.ts:235-259 (schema)

  JSON schema definition for delete_entities tool input: requires 'names' (array of strings) and 'memory_zone' (string), optional 'cascade_relations' boolean (default true).
  name: "delete_entities", description: "Delete entities from knowledge graph (memory)", inputSchema: { type: "object", properties: { names: { type: "array", items: {type: "string"}, description: "Names of entities to delete" }, memory_zone: { type: "string", description: "Memory zone specifier. Entities will be deleted from this zone." }, cascade_relations: { type: "boolean", description: "Whether to delete relations involving these entities (default: true)", default: true } }, required: ["names", "memory_zone"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } },
• src/index.ts:89-649 (registration)

  Tool registration in ListToolsRequestSchema handler: includes delete_entities in the list of available tools with its schema and description.
  server.setRequestHandler(ListToolsRequestSchema, async () => { return { tools: [ { name: "inspect_files", description: "Agent driven file inspection that uses AI to retrieve relevant content from multiple files.", inputSchema: { type: "object", properties: { file_paths: { type: "array", items: { type: "string" }, description: "Paths to the files (or directories) to inspect" }, information_needed: { type: "string", description: "Full description of what information is needed from the files, including the context of the information needed. Do not be vague, be specific. The AI agent does not have access to your context, only this \"information needed\" and \"reason\" fields. That's all it will use to decide that a line is relevant to the information needed. So provide a detailed specific description, listing all the details about what you are looking for." }, reason: { type: "string", description: "Explain why this information is needed to help the AI agent give better results. The more context you provide, the better the results will be." }, include_lines: { type: "boolean", description: "Whether to include the actual line content in the response, which uses more of your limited token quota, but gives more informatiom (default: false)" }, keywords: { type: "array", items: { type: "string" }, description: "Array of specific keywords related to the information needed. AI will target files that contain one of these keywords. REQUIRED and cannot be null or empty - the more keywords you provide, the better the results. Include variations, synonyms, and related terms." } }, required: ["file_paths", "information_needed", "include_lines", "keywords"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "inspect_knowledge_graph", description: "Agent driven knowledge graph inspection that uses AI to retrieve relevant entities and relations based on a query.", inputSchema: { type: "object", properties: { information_needed: { type: "string", description: "Full description of what information is needed from the knowledge graph, including the context of the information needed. Do not be vague, be specific. The AI agent does not have access to your context, only this \"information needed\" and \"reason\" fields. That's all it will use to decide that an entity is relevant to the information needed." }, reason: { type: "string", description: "Explain why this information is needed to help the AI agent give better results. The more context you provide, the better the results will be." }, include_entities: { type: "boolean", description: "Whether to include the full entity details in the response, which uses more of your limited token quota, but gives more information (default: false)" }, include_relations: { type: "boolean", description: "Whether to include the entity relations in the response (default: false)" }, keywords: { type: "array", items: { type: "string" }, description: "Array of specific keywords related to the information needed. AI will target entities that match one of these keywords. REQUIRED and cannot be null or empty - the more keywords you provide, the better the results. Include variations, synonyms, and related terms." }, memory_zone: { type: "string", description: "Memory zone to search in. If not provided, uses the default zone." }, entity_types: { type: "array", items: { type: "string" }, description: "Optional filter to specific entity types" } }, required: ["information_needed", "keywords"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "create_entities", description: "Create entities in knowledge graph (memory)", inputSchema: { type: "object", properties: { entities: { type: "array", items: { type: "object", properties: { name: {type: "string", description: "Entity name"}, entityType: {type: "string", description: "Entity type"}, observations: { type: "array", items: {type: "string"}, description: "Observations about this entity" } }, required: ["name", "entityType"] }, description: "List of entities to create" }, memory_zone: { type: "string", description: "Memory zone to create entities in." } }, required: ["entities", "memory_zone"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "update_entities", description: "Update entities in knowledge graph (memory)", inputSchema: { type: "object", properties: { entities: { type: "array", description: "List of entities to update", items: { type: "object", properties: { name: {type: "string"}, entityType: {type: "string"}, observations: { type: "array", items: {type: "string"} }, isImportant: {type: "boolean"} }, required: ["name"] } }, memory_zone: { type: "string", description: "Memory zone specifier. Entities will be updated in this zone." } }, required: ["entities", "memory_zone"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "delete_entities", description: "Delete entities from knowledge graph (memory)", inputSchema: { type: "object", properties: { names: { type: "array", items: {type: "string"}, description: "Names of entities to delete" }, memory_zone: { type: "string", description: "Memory zone specifier. Entities will be deleted from this zone." }, cascade_relations: { type: "boolean", description: "Whether to delete relations involving these entities (default: true)", default: true } }, required: ["names", "memory_zone"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "create_relations", description: "Create relationships between entities in knowledge graph (memory)", inputSchema: { type: "object", properties: { relations: { type: "array", description: "List of relations to create", items: { type: "object", properties: { from: {type: "string", description: "Source entity name"}, fromZone: {type: "string", description: "Optional zone for source entity, defaults to memory_zone or default zone. Must be one of the existing zones."}, to: {type: "string", description: "Target entity name"}, toZone: {type: "string", description: "Optional zone for target entity, defaults to memory_zone or default zone. Must be one of the existing zones."}, type: {type: "string", description: "Relationship type"} }, required: ["from", "to", "type"] } }, memory_zone: { type: "string", description: "Optional default memory zone specifier. Used if a relation doesn't specify fromZone or toZone." }, auto_create_missing_entities: { type: "boolean", description: "Whether to automatically create missing entities in the relations (default: true)", default: true } }, required: ["relations"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "delete_relations", description: "Delete relationships from knowledge graph (memory)", inputSchema: { type: "object", properties: { relations: { type: "array", description: "List of relations to delete", items: { type: "object", properties: { from: {type: "string", description: "Source entity name"}, to: {type: "string", description: "Target entity name"}, type: {type: "string", description: "Relationship type"} }, required: ["from", "to", "type"] } }, memory_zone: { type: "string", description: "Optional memory zone specifier. If provided, relations will be deleted from this zone." } }, required: ["relations"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "search_nodes", description: "Search entities using ElasticSearch query syntax. Supports boolean operators (AND, OR, NOT), fuzzy matching (~), phrases (\"term\"), proximity (\"terms\"~N), wildcards (*, ?), and boosting (^N). Examples: 'meeting AND notes', 'Jon~', '\"project plan\"~2'. All searches respect zone isolation.", inputSchema: { type: "object", properties: { query: { type: "string", description: "ElasticSearch query string." }, informationNeeded: { type: "string", description: "Important. Describe what information you are looking for, to give a precise context to the search engine AI agent. What questions are you trying to answer? Helps get more useful results." }, reason: { type: "string", description: "Explain why this information is needed to help the AI agent give better results. The more context you provide, the better the results will be." }, entityTypes: { type: "array", items: {type: "string"}, description: "Filter to specific entity types (OR condition if multiple)." }, limit: { type: "integer", description: "Max results (default: 20, or 5 with observations)." }, sortBy: { type: "string", enum: ["relevance", "recency", "importance"], description: "Sort by match quality, access time, or importance." }, includeObservations: { type: "boolean", description: "Include full entity observations (default: false).", default: false }, memory_zone: { type: "string", description: "Limit search to specific zone. Omit for default zone." }, }, required: ["query", "memory_zone", "informationNeeded", "reason"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "open_nodes", description: "Get details about specific entities in knowledge graph (memory) and their relations", inputSchema: { type: "object", properties: { names: { type: "array", items: {type: "string"}, description: "Names of entities to retrieve" }, memory_zone: { type: "string", description: "Optional memory zone to retrieve entities from. If not specified, uses the default zone." } }, required: ["names", "memory_zone"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "add_observations", description: "Add observations to an existing entity in knowledge graph (memory)", inputSchema: { type: "object", properties: { name: { type: "string", description: "Name of entity to add observations to" }, observations: { type: "array", items: {type: "string"}, description: "Observations to add to the entity" }, memory_zone: { type: "string", description: "Optional memory zone where the entity is stored. If not specified, uses the default zone." } }, required: ["memory_zone", "name", "observations"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "mark_important", description: "Mark entity as important in knowledge graph (memory) by boosting its relevance score", inputSchema: { type: "object", properties: { name: { type: "string", description: "Entity name" }, important: { type: "boolean", description: "Set as important (true - multiply relevance by 10) or not (false - divide relevance by 10)" }, memory_zone: { type: "string", description: "Optional memory zone specifier. If provided, entity will be marked in this zone." }, auto_create: { type: "boolean", description: "Whether to automatically create the entity if it doesn't exist (default: false)", default: false } }, required: ["memory_zone", "name", "important"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "get_recent", description: "Get recently accessed entities from knowledge graph (memory) and their relations", inputSchema: { type: "object", properties: { limit: { type: "integer", description: "Max results (default: 20 if includeObservations is false, 5 if true)" }, includeObservations: { type: "boolean", description: "Whether to include full entity observations in results (default: false)", default: false }, memory_zone: { type: "string", description: "Optional memory zone to get recent entities from. If not specified, uses the default zone." } }, required: ["memory_zone"], additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "list_zones", description: "List all available memory zones with metadata. When a reason is provided, zones will be filtered and prioritized based on relevance to your needs.", inputSchema: { type: "object", properties: { reason: { type: "string", description: "Reason for listing zones. What zones are you looking for? Why are you looking for them? The AI will use this to prioritize and filter relevant zones." } }, additionalProperties: false, "$schema": "http://json-schema.org/draft-07/schema#" } }, { name: "create_zone", description: "Create a new memory zone with optional description.", inputSchema: { type: "object", properties: { name: { type: "string", description: "Zone name (cannot be 'default')" }, shortDescription: { type: "string", description: "Short description of the zone." }, description: { type: "string", description: "Full zone description. Make it very descriptive and detailed." } }, required: ["name"] } }, { name: "delete_zone", description: "Delete a memory zone and all its entities/relations.", inputSchema: { type: "object", properties: { name: { type: "string", description: "Zone name to delete (cannot be 'default')" }, confirm: { type: "boolean", description: "Confirmation flag, must be true", default: false } }, required: ["name", "confirm"] } }, { name: "copy_entities", description: "Copy entities between zones with optional relation handling.", inputSchema: { type: "object", properties: { names: { type: "array", items: { type: "string" }, description: "Entity names to copy" }, source_zone: { type: "string", description: "Source zone" }, target_zone: { type: "string", description: "Target zone" }, copy_relations: { type: "boolean", description: "Copy related relationships (default: true)", default: true }, overwrite: { type: "boolean", description: "Overwrite if entity exists (default: false)", default: false } }, required: ["names", "source_zone", "target_zone"] } }, { name: "move_entities", description: "Move entities between zones (copy + delete from source).", inputSchema: { type: "object", properties: { names: { type: "array", items: { type: "string" }, description: "Entity names to move" }, source_zone: { type: "string", description: "Source zone" }, target_zone: { type: "string", description: "Target zone" }, move_relations: { type: "boolean", description: "Move related relationships (default: true)", default: true }, overwrite: { type: "boolean", description: "Overwrite if entity exists (default: false)", default: false } }, required: ["names", "source_zone", "target_zone"] } }, { name: "merge_zones", description: "Merge multiple zones with conflict resolution options.", inputSchema: { type: "object", properties: { source_zones: { type: "array", items: { type: "string" }, description: "Source zones to merge from" }, target_zone: { type: "string", description: "Target zone to merge into" }, delete_source_zones: { type: "boolean", description: "Delete source zones after merging", default: false }, overwrite_conflicts: { type: "string", enum: ["skip", "overwrite", "rename"], description: "How to handle name conflicts", default: "skip" } }, required: ["source_zones", "target_zone"] } }, { name: "zone_stats", description: "Get statistics for entities and relationships in a zone.", inputSchema: { type: "object", properties: { zone: { type: "string", description: "Zone name (omit for default zone)" } }, required: ["zone"] } }, { name: "get_time_utc", description: "Get the current UTC time in YYYY-MM-DD hh:mm:ss format", inputSchema: { type: "object", properties: {}, additionalProperties: false } } ] }; });
• src/kg-client.ts:337-445 (helper)

  Core deleteEntity method in KnowledgeGraphClient: initializes zone index, checks entity existence, optionally deletes related relations (intra-zone and cross-zone), deletes the entity document from Elasticsearch, returns success boolean.
  async deleteEntity( name: string, zone?: string, options?: { cascadeRelations?: boolean; } ): Promise<boolean> { // Validate entity name is not empty if (!name || name.trim() === '') { throw new Error('Entity name cannot be empty'); } const actualZone = zone || this.defaultZone; await this.initialize(actualZone); // Default to true for cascading relation deletion const cascadeRelations = options?.cascadeRelations !== false; try { // First, check if the entity exists const entity = await this.getEntityWithoutUpdatingLastRead(name, actualZone); if (!entity) { return false; } const indexName = this.getIndexForZone(actualZone); // Delete relations involving this entity if cascading is enabled if (cascadeRelations) { console.error(`Cascading relations for entity ${name} in zone ${actualZone}`); // First, delete relations within the same zone await this.client.deleteByQuery({ index: indexName, body: { query: { bool: { must: [ { term: { type: 'relation' } }, { bool: { should: [ { term: { from: name } }, { term: { to: name } } ] } } ] } } }, refresh: true }); // Then, delete cross-zone relations where this entity is involved // These are stored in the KG_RELATIONS_INDEX await this.client.deleteByQuery({ index: KG_RELATIONS_INDEX, body: { query: { bool: { must: [ { bool: { should: [ { bool: { must: [ { term: { from: name } }, { term: { fromZone: actualZone } } ] } }, { bool: { must: [ { term: { to: name } }, { term: { toZone: actualZone } } ] } } ] } } ] } } }, refresh: true }); } else { console.error(`Skipping relation cascade for entity ${name} in zone ${actualZone}`); } // Delete the entity await this.client.delete({ index: indexName, id: `entity:${name}`, refresh: true }); return true; } catch (error) { if (error.statusCode === 404) { return false; } throw error; } }