Description

The OpenCode Desktop app (Tauri-based) gets stuck on the "Starting server..." loading screen on macOS. The root cause is the -i (interactive) flag used when spawning the sidecar CLI process.

Root Cause

In packages/desktop/src-tauri/src/lib.rs (around line 134-145), the sidecar is spawned via:

app.shell().command(&shell)
  .args(["-il", "-c", &format!("\"{}\" serve --port={}", sidecar.display(), port)])

The -i flag forces interactive mode, which causes zsh to:

1. Load ~/.zshrc (oh-my-zsh, themes, plugins)
2. Initialize ZLE (Zsh Line Editor) hooks
3. Set up prompt rendering, syntax highlighting, autosuggestions

Since the desktop app has no TTY (it's a GUI process), ZLE-dependent plugins like zsh-syntax-highlighting and zsh-autosuggestions hang indefinitely during initialization — they expect terminal I/O that doesn't exist.

Reproduction

# This works (non-interactive):
zsh -c "/Applications/OpenCode.app/Contents/MacOS/opencode-cli debug config"

# This works (login only, no interactive):
zsh -lc "/Applications/OpenCode.app/Contents/MacOS/opencode-cli debug config"

# This HANGS (interactive + login):
zsh -il -c "/Applications/OpenCode.app/Contents/MacOS/opencode-cli debug config"

Environment

• OS: macOS Sequoia (Apple Silicon)
• OpenCode Desktop: v1.2.13
• Shell: /bin/zsh with oh-my-zsh + zsh-syntax-highlighting + zsh-autosuggestions (extremely common setup)
• Theme: agnoster

Desktop App Logs (failing)

INFO opencode_lib: Initializing app
INFO opencode_lib: Main and loading windows created
INFO opencode_lib: Setting up server connection
INFO opencode_lib::cli: CLI is up to date, skipping sync
← Stops here. Never reaches "Attempting server connection"

Suggested Fix

Change the shell invocation from -il to -lc:

// Before (hangs when user has ZLE plugins):
.args(["-il", "-c", &format!("\"{}\" serve --port={}", sidecar.display(), port)])

// After (login shell for PATH, but no interactive mode):
.args(["-lc", &format!("\"{}\" serve --port={}", sidecar.display(), port)])

The -l (login) flag is sufficient to load ~/.zprofile for PATH setup (Homebrew, nvm, etc.). The -i flag is unnecessary for a non-interactive subprocess and actively harmful in a no-TTY environment.

Related Issues

• Desktop sidecar spawn can time out on macOS with interactive shell startup #13926 — Same symptom (CLOSED, but the -i flag is still present in v1.2.13)
• Desktop app fails to start on Linux/Wayland - 'open terminal failed: not a terminal' #9505 — Linux/Wayland: "open terminal failed: not a terminal" (same root cause)
• Opencode Desktop error with nushell as default shell #8716 — nushell as default shell causes spawn failure (same $SHELL -il -c pattern)
• [GUI - Macos] An error occurred while loading the application #13597 — macOS: "Health check timed out" (same symptom)

Workaround

Users can add TTY guards to their ~/.zshrc to prevent blocking in non-TTY environments:

# Before oh-my-zsh theme/plugin setup:
if [[ -t 0 ]]; then
  plugins=(git zsh-syntax-highlighting zsh-autosuggestions)
else
  plugins=(git)
fi

But this is a workaround — the app should not require users to modify their shell configuration.