feat(KB-604): include task context in notifications with description fallback

- Add formatTaskIdentifier helper to format task references with title or description fallback
- Update notification messages to include task identifier context
- Show truncated description (200 chars) prefixed with task ID when no title
- Add comprehensive tests for formatTaskIdentifier function
- Add changeset for notification improvements and update AGENTS.md

packages/engine/src/notifier.test.ts

@@ -220,18 +220,56 @@ describe("NtfyNotifier", () => {
       expect(fetchMock).not.toHaveBeenCalled();
     });
 
-    it("uses task ID when title is not available", async () => {
+    it("uses task ID and description when title is not available", async () => {
       notifier = new NtfyNotifier(store);
       await notifier.start();
 
-      store.triggerTaskMoved(createTask("KB-001"), "in-progress", "in-review");
+      const taskWithoutTitle = { ...createTask("KB-001"), description: "Implement user authentication flow" };
+      store.triggerTaskMoved(taskWithoutTitle, "in-progress", "in-review");
 
       await new Promise(resolve => setTimeout(resolve, 10));
 
       expect(fetchMock).toHaveBeenCalledWith(
         "https://ntfy.sh/test-topic",
         expect.objectContaining({
-          body: 'Task "KB-001" is ready for review',
+          body: 'Task "KB-001: Implement user authentication flow" is ready for review',
+        })
+      );
+    });
+
+    it("truncates description to 200 characters when no title is set", async () => {
+      notifier = new NtfyNotifier(store);
+      await notifier.start();
+
+      const longDescription = "A".repeat(250);
+      const taskWithoutTitle = { ...createTask("KB-001"), description: longDescription };
+      store.triggerTaskMoved(taskWithoutTitle, "in-progress", "in-review");
+
+      await new Promise(resolve => setTimeout(resolve, 10));
+
+      const expectedSnippet = "A".repeat(200) + "...";
+      expect(fetchMock).toHaveBeenCalledWith(
+        "https://ntfy.sh/test-topic",
+        expect.objectContaining({
+          body: `Task "KB-001: ${expectedSnippet}" is ready for review`,
+        })
+      );
+    });
+
+    it("does not truncate description at exactly 200 characters", async () => {
+      notifier = new NtfyNotifier(store);
+      await notifier.start();
+
+      const exactDescription = "B".repeat(200);
+      const taskWithoutTitle = { ...createTask("KB-001"), description: exactDescription };
+      store.triggerTaskMoved(taskWithoutTitle, "in-progress", "in-review");
+
+      await new Promise(resolve => setTimeout(resolve, 10));
+
+      expect(fetchMock).toHaveBeenCalledWith(
+        "https://ntfy.sh/test-topic",
+        expect.objectContaining({
+          body: `Task "KB-001: ${exactDescription}" is ready for review`,
         })
       );
     });

packages/engine/src/notifier.ts

@@ -7,6 +7,22 @@ export interface NtfyNotifierOptions {
   ntfyBaseUrl?: string;
 }
 
+/**
+ * Format a task identifier for notifications.
+ * - If title exists: returns "{title}"
+ * - If no title: returns "{id}: {first 200 chars of description}" (truncated with "..." if > 200)
+ */
+function formatTaskIdentifier(task: Task): string {
+  if (task.title) {
+    return task.title;
+  }
+  const maxLen = 200;
+  const snippet = task.description.length > maxLen
+    ? task.description.slice(0, maxLen) + "..."
+    : task.description;
+  return `${task.id}: ${snippet}`;
+}
+
 /** Minimal store interface needed by NtfyNotifier */
 interface NtfyNotifierStore {
   getSettings(): Promise<Settings> | Settings;
@@ -104,7 +120,7 @@ export class NtfyNotifier {
         this.sendNotification(
           this.config.topic!,
           `Task ${task.id} completed`,
-          `Task "${task.title ?? task.id}" is ready for review`,
+          `Task "${formatTaskIdentifier(task)}" is ready for review`,
           "default",
         ),
       );
@@ -123,7 +139,7 @@ export class NtfyNotifier {
         this.sendNotification(
           this.config.topic!,
           `Task ${task.id} failed`,
-          `Task "${task.title ?? task.id}" has failed and needs attention`,
+          `Task "${formatTaskIdentifier(task)}" has failed and needs attention`,
           "high",
         ),
       );
@@ -139,7 +155,7 @@ export class NtfyNotifier {
         this.sendNotification(
           this.config.topic!,
           `Task ${result.task.id} merged`,
-          `Task "${result.task.title ?? result.task.id}" has been merged to main`,
+          `Task "${formatTaskIdentifier(result.task)}" has been merged to main`,
           "default",
         ),
       );