Windows: opencode prints help and exits for *any* command. Desktop GUI fails to spawn server (1.1.12–1.1.15) #8233

Description

Summary：

On Windows, opencode starts and prints the banner, but for any command it only prints the help text and exits (including opencode, opencode ., opencode run ..., opencode serve ..., and even with --print-logs --log-level DEBUG). The Desktop GUI (Tauri) also fails to spawn the OpenCode server; its captured STDOUT shows the same help output.

This happens across multiple shells (PowerShell, Git Bash) and across versions (1.1.13 and 1.1.15). It also persists even when running the real Windows binary directly (opencode-windows-x64\bin\opencode.exe). But yesterday I could still use ohmyopencode happily, and this morning it successfully launched as well, but after an automatic update, it can no longer start properly, even reverting to a previous version and reinstalling doesn't help

Expected behavior

• opencode (or opencode .) should start the TUI.
• opencode run "hello" should create/run a session.
• opencode serve --port 0 should start a headless server.
• Desktop GUI should be able to spawn the server process.

Actual behavior

• opencode prints the banner and then the global help list of commands, and exits.
• opencode run ... prints only the opencode run help and exits.
• opencode serve ... prints only the opencode serve help and exits.
• Adding --print-logs --log-level DEBUG does not produce any additional output besides help.
• Desktop GUI shows error "Failed to spawn OpenCode Server" and the captured STDOUT is just the same banner + help output.

Plugins

"oh-my-opencode",
"[email protected]",
"opencode-openai-codex-auth"

OpenCode version

• 1.1.13 (Chocolatey/Scoop)
• 1.1.15 (npm + opencode-windows-x64)
• OpenCode Desktop (GUI): <1.1.12–1.1.15> (downloaded installer)

Steps to reproduce

(minimal)Install the Windows binary package and locate the real exe:

npm i -g opencode-ai@1.1.15
npm i -g opencode-windows-x64@1.1.15

$npmRoot=(npm root -g).Trim()
$realExe=Join-Path $npmRoot 'opencode-windows-x64\bin\opencode.exe'
& $realExe -v

### Screenshot and/or share link

_No response_

### Operating System

- OS: Windows 10

### Terminal

- Shells tested:
- PowerShell/cmd.exe
- Git Bash
- Node.js: `<v24.11.1>`
- npm: `<10.8.1>`