IaC Memory MCP Server

Instructions

Implementation Reference

• src/iac_memory_mcp_server/tools/entity.py:89-115 (handler)

  The MCP tool handler for delete_entity. It validates, logs the operation, calls execute_delete_entity, and handles errors by raising McpError.

  async def handle_delete_entity(db: Any, arguments: Dict[str, Any], operation_id: str) -> list[types.TextContent | types.ImageContent | types.EmbeddedResource]:
      """Handle delete_entity tool."""
      try:
          logger.info(
              "Deleting entity",
              extra={
                  "entity_id": arguments.get("entity_id"),
                  "operation_id": operation_id,
              },
          )
  
          # Execute deletion
          return execute_delete_entity(db, arguments)
  
      except Exception as e:
          error_msg = f"Failed to delete entity: {str(e)}"
          logger.error(error_msg, extra={"operation_id": operation_id})
          raise McpError(
              types.ErrorData(
                  code=types.INTERNAL_ERROR,
                  message=error_msg,
                  data={
                      "tool": "delete_entity",
                      "operation_id": operation_id,
                  },
              )
          )

• src/iac_memory_mcp_server/db/tools.py:329-334 (schema)

  JSON schema defining the input parameters for the delete_entity tool, requiring an 'id' string.

  "delete_entity": {
      "type": "object",
      "description": "Remove an entity and its relationships from the knowledge graph",
      "required": ["id"],
      "properties": {"id": {"type": "string", "description": "Entity ID"}},
  },

• src/iac_memory_mcp_server/tools/entity.py:150-155 (registration)

  Dictionary registering the delete_entity tool handler along with other entity tools.

  entity_tool_handlers = {
      "create_entity": handle_create_entity,
      "update_entity": handle_update_entity,
      "delete_entity": handle_delete_entity,
      "view_relationships": handle_view_relationships,
  }

• src/iac_memory_mcp_server/db/entities.py:208-218 (helper)

  Helper function called by the handler to perform the deletion logic, invoking the core delete_entity function and returning a TextContent response.

  def execute_delete_entity(
      db: DatabaseManager, arguments: Dict[str, Any]
  ) -> List[TextContent]:
      """Execute delete entity operation."""
      logger.info("Deleting entity", extra={"args": arguments})
  
      success = delete_entity(db, arguments["id"])
      if not success:
          raise DatabaseError(f"Entity not found: {arguments['id']}")
  
      return [TextContent(type="text", text=f"Deleted entity {arguments['id']}")]

• src/iac_memory_mcp_server/db/entities.py:64-76 (helper)

  Core database operation that deletes observations and the entity from the SQLite database, returning success boolean.

  def delete_entity(db: DatabaseManager, entity_id: str) -> bool:
      """Delete an entity and its related observations."""
      try:
          with db.get_connection() as conn:
              conn.execute("BEGIN TRANSACTION")
              conn.execute("DELETE FROM observations WHERE entity_id = ?", (entity_id,))
              cursor = conn.execute("DELETE FROM entities WHERE id = ?", (entity_id,))
              affected = cursor.rowcount > 0
              conn.commit()
              return affected
      except sqlite3.Error as e:
          raise DatabaseError(f"Delete failed: {str(e)}")