Google Tasks MCP Server

Instructions

Implementation Reference

• src/index.ts:282-323 (handler)

  Handler for the 'complete_task' tool: Validates arguments, extracts taskId and status, patches the task status via Google Tasks API, and returns the updated task data.

  if (request.params.name === "complete_task") {
  
    if (!isValidCreateTaskArgs(request.params.arguments)) {
      throw new McpError(
        ErrorCode.InvalidParams,
        "Invalid arguments for creating a task. 'title' must be a string, and 'notes' must be a string or undefined."
      );
    }
    const args = request.params.arguments;
    const taskId  = args.taskId;
    const newStatus  = args.status;
  
    if (!taskId) {
      throw new McpError(
        ErrorCode.InvalidParams,
        "The 'taskId' field is required."
      );
    }
  
    try {
      // Durumu güncelle
      const updateResponse = await tasks.tasks.patch({
        tasklist: "@default",
        task: taskId,
        requestBody: { status: newStatus },
      });
  
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(updateResponse.data, null, 2),
          },
        ],
      };
    } catch (error) {
      throw new McpError(
        ErrorCode.InternalError,
        `Tasks API error: ${error}`
      );
    }
  }

• src/index.ts:173-184 (registration)

  Tool registration in the list_tools response, defining name, description, and input schema for 'complete_task'.

  {
    name: "complete_task",
    description: "Toggle the completion status of a task",
    inputSchema: {
      type: "object",
      properties: {
        taskId: { type: "string", description: "ID of the task to toggle completion status" },
        status: { type: "string", description: "Status of task, needsAction or completed" },
      },
      required: ["taskId"],
    },
  },

• src/index.ts:44-53 (schema)

  Helper validation function used in the complete_task handler to check arguments (though originally for create_task).

  export function isValidCreateTaskArgs(args: any): args is CreateTaskArgs {
    return (
      typeof args === "object" &&
      args !== null &&
      (args.title === undefined || typeof args.title === "string") &&
      (args.notes === undefined || typeof args.notes === "string") &&
      (args.taskId === undefined || typeof args.taskId === "string") &&
      (args.status === undefined || typeof args.status === "string")
    );
  }