From 3c1fbdd3f3fd9643b542b8fa78e26d6443226fbd Mon Sep 17 00:00:00 2001
From: roboomp <omp@can.ac>
Date: Wed, 22 Jul 2026 16:42:23 +0000
Subject: [PATCH] fix(coding-agent/launch): surfaced pre-ready exits in TUI

The model-facing start content reported when a process exited before readiness,
but launchRenderResult rebuilt the interactive result solely from structured
details and dropped that explanation. Mirror the terminal-without-readyAt
condition in the TUI start renderer and add a renderer contract test.

Fixes #6303
---
 packages/coding-agent/src/tools/hub/launch.ts |  2 ++
 .../test/tools/launch-renderer.test.ts        | 28 +++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/packages/coding-agent/src/tools/hub/launch.ts b/packages/coding-agent/src/tools/hub/launch.ts
index eb3731513..6aeca9ba7 100644
--- a/packages/coding-agent/src/tools/hub/launch.ts
+++ b/packages/coding-agent/src/tools/hub/launch.ts
@@ -442,6 +442,8 @@ export function launchRenderResult(
 								: "Readiness timed out; the process is still running.",
 						),
 					);
+				} else if (params.ready && daemon && daemon.readyAt === undefined && TERMINAL_STATES[daemon.state]) {
+					body.push(theme.fg("warning", "Process exited before readiness was observed."));
 				}
 				break;
 			}
diff --git a/packages/coding-agent/test/tools/launch-renderer.test.ts b/packages/coding-agent/test/tools/launch-renderer.test.ts
index a0572a5d1..182806773 100644
--- a/packages/coding-agent/test/tools/launch-renderer.test.ts
+++ b/packages/coding-agent/test/tools/launch-renderer.test.ts
@@ -167,6 +167,34 @@ describe("hub launch rendering", () => {
 		expect(rendered.some(line => line.includes("spawn bun ENOENT"))).toBe(true);
 	});
 
+	it("surfaces a pre-ready exit in the interactive start result", async () => {
+		const uiTheme = await theme();
+		const rendered = lines(
+			hubToolRenderer.renderResult(
+				{
+					content: [{ type: "text", text: "Process exited before readiness was observed." }],
+					details: {
+						op: "start",
+						timedOut: false,
+						daemon: daemon({
+							state: "exited",
+							pid: undefined,
+							exitedAt: Date.now(),
+							exitCode: 0,
+							readyAt: undefined,
+						}),
+					} satisfies LaunchToolDetails,
+				},
+				{ expanded: false, isPartial: false },
+				uiTheme,
+				{ op: "start", name: "web", application: "bun", ready: { log: "LISTENING" } },
+			),
+		);
+		expect(rendered[0]).toContain("Launch start");
+		expect(rendered[0]).toContain("exited");
+		expect(rendered.some(line => line.includes("Process exited before readiness was observed."))).toBe(true);
+	});
+
 	it("names the unmet readiness condition instead of a contradictory Ready + timed-out pair", async () => {
 		const uiTheme = await theme();
 		const rendered = lines(