From d4232d487d17a64db541e268a8e3555ada38b8a3 Mon Sep 17 00:00:00 2001
From: southseact-3d <hetheringtonliam7@gmail.com>
Date: Tue, 17 Feb 2026 19:03:27 +0000
Subject: [PATCH] fix: skip opencode undo when message has zero output

Prevents error when undoing messages that produced no output.
Checks for reply, partialOutput, or done status before sending
/undo command to opencode.
---
 chat/server.js | 29 ++++++++++++++++++-----------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/chat/server.js b/chat/server.js
index 07b063a..25a7d4f 100644
--- a/chat/server.js
+++ b/chat/server.js
@@ -17334,21 +17334,28 @@ async function handleUndoMessage(req, res, sessionId, messageId, userId) {
   }
 
   try {
-    log('Sending undo command to opencode', { sessionId, messageId, opencodeSessionId: session.opencodeSessionId });
+    // Check if message had any output - if not, skip the opencode undo
+    const hasOutput = !!(message.reply || message.partialOutput) || message.status === 'done';
 
-    const cliCommand = resolveCliCommand('opencode');
-    const args = ['--message', '/undo'];
+    if (hasOutput) {
+      log('Sending undo command to opencode', { sessionId, messageId, opencodeSessionId: session.opencodeSessionId });
 
-    // Add session if we have one
-    if (session.opencodeSessionId) {
-      args.push('--session', session.opencodeSessionId);
+      const cliCommand = resolveCliCommand('opencode');
+      const args = ['--message', '/undo'];
+
+      // Add session if we have one
+      if (session.opencodeSessionId) {
+        args.push('--session', session.opencodeSessionId);
+      }
+
+      await runCommand(cliCommand, args, {
+        cwd: session.workspaceDir || REPO_ROOT,
+        timeout: 30000
+      });
+    } else {
+      log('Skipping undo command - message had zero output', { sessionId, messageId });
     }
 
-    await runCommand(cliCommand, args, {
-      cwd: session.workspaceDir || REPO_ROOT,
-      timeout: 30000
-    });
-
     // Clear todos from the message when undone
     if (message.todos) {
       const todoCount = message.todos.length;