chore: address delegation review cleanup

Author: edelauna

src/core/tools/AttemptCompletionTool.ts

@@ -86,6 +86,7 @@ export class AttemptCompletionTool extends BaseTool<"attempt_completion"> {
 				// to prevent duplicate tool_results when user revisits from history
 				const provider = task.providerRef.deref() as DelegationProvider | undefined
 				if (provider) {
+					let historyLookupTaskId = task.taskId
 					try {
 						const { historyItem } = await provider.getTaskWithId(task.taskId)
 						const status = historyItem?.status
@@ -96,6 +97,7 @@ export class AttemptCompletionTool extends BaseTool<"attempt_completion"> {
 							// This shows the user the completion result and waits for acceptance
 							// without injecting another tool_result to the parent
 						} else if (status === "active") {
+							historyLookupTaskId = task.parentTaskId
 							const { historyItem: parentHistory } = await provider.getTaskWithId(task.parentTaskId)
 
 							if (parentHistory.status === "delegated" && parentHistory.awaitingChildId === task.taskId) {
@@ -110,6 +112,9 @@ export class AttemptCompletionTool extends BaseTool<"attempt_completion"> {
 									this.emitTaskCompleted(task)
 								}
 								if (delegation !== "continue") return
+							} else {
+								// Parent already detached, such as when the user cancelled this child.
+								// Fall through to the normal completion ask flow.
 							}
 						} else {
 							// Unexpected status (undefined or "delegated") - log error and skip delegation
@@ -124,7 +129,7 @@ export class AttemptCompletionTool extends BaseTool<"attempt_completion"> {
 					} catch (err) {
 						// If we can't get the history, log error and skip delegation
 						console.error(
-							`[AttemptCompletionTool] Failed to get history for task ${task.taskId}: ${(err as Error)?.message ?? String(err)}. ` +
+							`[AttemptCompletionTool] Failed to get history for task ${historyLookupTaskId}: ${(err as Error)?.message ?? String(err)}. ` +
 								`Skipping delegation.`,
 						)
 						// Fall through to normal completion ask flow

src/core/tools/__tests__/attemptCompletionTool.spec.ts

@@ -534,7 +534,7 @@ describe("attemptCompletionTool", () => {
 				expect(mockPushToolResult).toHaveBeenCalledWith("")
 			})
 
-			it("does not delegate a lineage-preserving subtask when the parent is no longer awaiting it", async () => {
+			it("does not resume the parent when the parent is no longer awaiting this child", async () => {
 				const block: AttemptCompletionToolUse = {
 					type: "tool_use",
 					name: "attempt_completion",

src/core/webview/ClineProvider.ts

@@ -2972,6 +2972,9 @@ export class ClineProvider
 						awaitingChildId: undefined,
 					})
 
+					this.log(
+						`[cancelTask] Detached delegated parent ${task.parentTaskId}: delegated → active (child ${task.taskId} cancelled)`,
+					)
 					parentTask = undefined
 					rootTask = undefined
 				}