Task Manager MCP Server

Instructions

Implementation Reference

• src/tools.ts:129-189 (handler)

  Executes the update_task tool: validates args with UpdateTaskSchema, loads tasks, finds task by partial ID, updates fields, saves, returns formatted response.

  export async function updateTask(args: unknown) {
    // Validate input
    const validated = UpdateTaskSchema.parse(args);
  
    // Load tasks
    const storage = await loadTasks();
  
    // Find task by ID (partial match)
    const taskIndex = storage.tasks.findIndex((t) =>
      t.id.startsWith(validated.taskId)
    );
  
    if (taskIndex === -1) {
      return {
        content: [
          {
            type: "text",
            text: `❌ Task with ID ${validated.taskId} not found.`,
          },
        ],
      };
    }
  
    const task = storage.tasks[taskIndex]!;
  
    // Update fields if provided
    if (validated.title !== undefined) {
      task.title = validated.title;
    }
    if (validated.description !== undefined) {
      task.description = validated.description;
    }
    if (validated.priority !== undefined) {
      task.priority = validated.priority as Priority;
    }
    if (validated.category !== undefined) {
      task.category = validated.category;
    }
    if (validated.dueDate !== undefined) {
      task.dueDate = validated.dueDate;
    }
    if (validated.status !== undefined) {
      task.status = validated.status as Status;
      if (validated.status === "completed" && !task.completedAt) {
        task.completedAt = new Date().toISOString();
      } else if (validated.status !== "completed") {
        task.completedAt = undefined;
      }
    }
  
    await saveTasks(storage);
  
    return {
      content: [
        {
          type: "text",
          text: `✅ Task updated successfully!\n\n${formatTask(task)}`,
        },
      ],
    };
  }

• src/types.ts:48-59 (schema)

  Zod schema defining the input validation for update_task tool arguments.

  export const UpdateTaskSchema = z.object({
    taskId: z.string().min(8, "Task ID must be at least 8 characters"),
    title: z.string().optional(),
    description: z.string().optional(),
    priority: z.enum(["low", "medium", "high"]).optional(),
    category: z.string().optional(),
    dueDate: z
      .string()
      .regex(/^\d{4}-\d{2}-\d{2}$/, "Date must be YYYY-MM-DD")
      .optional(),
    status: z.enum(["pending", "in_progress", "completed"]).optional(),
  });

• src/index.ts:84-125 (registration)

  Registers the update_task tool in the TOOLS array with name, description, and JSON inputSchema for MCP ListToolsRequest.

  {
    name: "update_task",
    description: "Update an existing task",
    inputSchema: {
      type: "object",
      properties: {
        taskId: {
          type: "string",
          description: "Task ID (use first 8 characters)",
          minLength: 8,
        },
        title: {
          type: "string",
          description: "New title",
        },
        description: {
          type: "string",
          description: "New description",
        },
        priority: {
          type: "string",
          enum: ["low", "medium", "high"],
          description: "New priority",
        },
        category: {
          type: "string",
          description: "New category",
        },
        dueDate: {
          type: "string",
          pattern: "^\\d{4}-\\d{2}-\\d{2}$",
          description: "New due date (YYYY-MM-DD)",
        },
        status: {
          type: "string",
          enum: ["pending", "in_progress", "completed"],
          description: "New status",
        },
      },
      required: ["taskId"],
    },
  },

• src/index.ts:221-222 (registration)

  Dispatches calls to the updateTask handler function in the MCP CallToolRequest switch statement.

  case "update_task":
    return await updateTask(args);