diff --git a/packages/opencode/src/cli/cmd/tui/thread.ts b/packages/opencode/src/cli/cmd/tui/thread.ts
index 05714268545b..9c973ec49992 100644
--- a/packages/opencode/src/cli/cmd/tui/thread.ts
+++ b/packages/opencode/src/cli/cmd/tui/thread.ts
@@ -156,9 +156,11 @@ export const TuiThreadCommand = cmd({
       },
     })
 
-    setTimeout(() => {
-      client.call("checkUpgrade", { directory: cwd }).catch(() => {})
-    }, 1000)
+    // checkUpgrade disabled: calling Instance.provide() with InstanceBootstrap
+    // causes worker state corruption that breaks Ctrl-C handling
+    // setTimeout(() => {
+    //   client.call("checkUpgrade", { directory: cwd }).catch(() => {})
+    // }, 1000)
 
     await tuiPromise
   },