improve parallel mode init error messages (#3426)

* improve parallel mode init error messages

* add changeset

Author: iscekic

.changeset/silver-eagles-post.md

@@ -0,0 +1,5 @@
+---
+"@kilocode/cli": patch
+---
+
+Improves error message clarity when initiating parallel mode

cli/src/parallel/__tests__/determineBranch.test.ts

@@ -55,7 +55,7 @@ describe("determineParallelBranch", () => {
 			}
 
 			await expect(determineParallelBranch(input)).rejects.toThrow(
-				"Error: parallel mode requires the current working directory to be a git repository",
+				"Parallel mode requires the current working directory to be a git repository",
 			)
 		})
 
@@ -111,9 +111,7 @@ describe("determineParallelBranch", () => {
 				existingBranch,
 			}
 
-			await expect(determineParallelBranch(input)).rejects.toThrow(
-				`Error: Branch "${existingBranch}" does not exist`,
-			)
+			await expect(determineParallelBranch(input)).rejects.toThrow(`Branch "${existingBranch}" does not exist`)
 
 			expect(branchExists).toHaveBeenCalledWith(mockCwd, existingBranch)
 		})

cli/src/parallel/determineBranch.ts

@@ -27,7 +27,7 @@ export async function determineParallelBranch({
 	const { isRepo, branch } = await getGitInfo(cwd)
 
 	if (!isRepo) {
-		const errorMessage = "Error: parallel mode requires the current working directory to be a git repository"
+		const errorMessage = "Parallel mode requires the current working directory to be a git repository"
 		logs.error(errorMessage, "ParallelMode")
 		throw new Error(errorMessage)
 	}
@@ -46,7 +46,7 @@ export async function determineParallelBranch({
 		const exists = await branchExists(cwd, existingBranch)
 
 		if (!exists) {
-			const errorMessage = `Error: Branch "${existingBranch}" does not exist`
+			const errorMessage = `Branch "${existingBranch}" does not exist`
 			logs.error(errorMessage, "ParallelMode")
 			throw new Error(errorMessage)
 		}

cli/src/parallel/parallel.ts

@@ -61,16 +61,28 @@ export type Input = {
  * Get parameters for parallel mode execution
  */
 export async function getParallelModeParams({ cwd, prompt, existingBranch }: Input) {
-	// Determine branch and worktree path
-	const { worktreeBranch, worktreePath } = await determineParallelBranch({
-		cwd,
-		prompt,
-		...(existingBranch && { existingBranch }),
-	})
-
-	return {
-		worktreeBranch,
-		worktreePath,
+	try {
+		// Determine branch and worktree path
+		const { worktreeBranch, worktreePath } = await determineParallelBranch({
+			cwd,
+			prompt,
+			...(existingBranch && { existingBranch }),
+		})
+
+		return {
+			worktreeBranch,
+			worktreePath,
+		}
+	} catch (error) {
+		const message = error instanceof Error ? error.message : String(error)
+
+		logs.error("Error determining parallel branch", "ParallelMode", {
+			error: message,
+		})
+
+		console.error(`Failed to start parallel mode: ${message}`)
+
+		process.exit(1)
 	}
 }
 
@@ -79,7 +91,7 @@ const agentCommitInstruction =
 
 /**
  * Finish parallel mode by having the extension agent generate a commit message and committing changes,
- * then cleaning up the git worktree
+ * then cleaning up the git worktree.
  * This function should be called from the CLI dispose method when in parallel mode
  * Since it's part of the dispose flow, this function must never throw an error
  */