packages/desktop dev mode crashes in browser - Tauri APIs called unconditionally

[kyashrathore]

Description

The packages/desktop README documents a web-only development mode that doesn't actually work. The code calls Tauri APIs unconditionally without checking if running in a Tauri context, causing immediate crashes when running in a browser.

Documentation Claims

From packages/desktop/README.md (lines 16-20):

If you only want the web dev server (no native shell):

\`\`\`bash
bun run --cwd packages/desktop dev
\`\`\`

This suggests the desktop package supports browser-only development for quick iteration without the native shell overhead.

Actual Behavior

Running bun run --cwd packages/desktop dev and opening http://localhost:1420 in a browser results in multiple crashes:

Error 1: OS Type Detection

TypeError: Cannot read properties of undefined (reading 'os_type')
    at type (@tauri-apps_plugin-os.js:20:47)
    at index.tsx:47:18

Location: src/index.tsx:47 - calls ostype() unconditionally in createPlatform()

Error 2: Menu Creation

TypeError: Cannot read properties of undefined (reading 'os_type')
    at type (@tauri-apps_plugin-os.js:20:47)
    at createMenu (menu.ts:10:7)

Location: src/menu.ts:10 - calls ostype() without checking Tauri context

Error 3: WebView Zoom

TypeError: Cannot read properties of undefined (reading 'os_type')
    at type (@tauri-apps_plugin-os.js:20:47)
    at webview-zoom.ts:8:17

Location: src/webview-zoom.ts:8 - calls ostype() at module initialization

Error 4: Server Readiness Check

TypeError: Cannot read properties of undefined (reading 'invoke')
    at invoke (chunk-IT22SQDD.js:107:37)
    at ServerGate (index.tsx:324:45)

Location: src/index.tsx:324 - calls invoke("ensure_server_ready") unconditionally

Root Cause

The code assumes it's always running in a Tauri context and calls Tauri APIs directly without checking "__TAURI__" in window. This breaks the documented browser-only dev mode.

Files Affected

All these files call Tauri APIs unconditionally:

1. src/index.tsx

   • ostype() - line ~47
   • invoke("ensure_server_ready") - line ~324
   • invoke("kill_sidecar") - multiple locations
   • invoke("get_default_server_url") - line ~315
   • invoke("set_default_server_url") - line ~320
   • invoke("parse_markdown_command") - line ~324
   • open(), save() - file picker dialogs
   • check() - updater
   • tauriFetch() - HTTP requests
   • isPermissionGranted(), requestPermission() - notifications
   • relaunch() - restart functionality

2. src/menu.ts

   • ostype() - line 10

3. src/webview-zoom.ts

   • ostype() - line 8
   • invoke("plugin:webview|set_webview_zoom") - line 27

Proposed Solutions

Option 1: Fix the Code (Recommended)

Add Tauri context detection and graceful fallbacks:

const isTauri = "__TAURI__" in window

// Example fixes:
const OS_NAME = isTauri ? ostype() : "unknown"

export async function createMenu() {
  if (!isTauri || ostype() !== "macos") return
  // ... rest of menu code
}

const [serverData] = createResource<ServerReadyData>(() => {
  if (!isTauri) {
    return Promise.resolve({ url: "http://127.0.0.1:4096", password: null })
  }
  return invoke("ensure_server_ready").then(...)
})

This would make the documented browser-only mode actually work.

Option 2: Update Documentation

If browser-only mode isn't intended to be supported, remove the misleading documentation:

- If you only want the web dev server (no native shell):
- 
- ```bash
- bun run --cwd packages/desktop dev
- ```

And clarify that tauri dev is the only supported development mode.

Impact

This affects developers who:

• Don't have Tauri prerequisites installed
• Want quick UI iteration without native shell overhead
• Are following the documented workflow

Environment

• Platform: macOS (but affects all platforms)
• Node: v22.22.0
• Bun: v1.3.6
• Package: @opencode-ai/desktop v1.1.33

Additional Context

The web-only dev mode is a common pattern for Tauri/Electron apps to enable faster development iteration. The infrastructure (Vite dev server) is already in place - it just needs the Tauri API guards to make it work as documented.

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• Improve packages/desktop README with environment setup instructions #8488: Improve packages/desktop README with environment setup instructions (related README documentation issues)
• Fix: Desktop app menus only work on macOS, windows have rendering issues #9873: Fix: Desktop app menus only work on macOS, windows have rendering issues (related to menu.ts issues mentioned in this report)

Feel free to ignore if none of these address your specific case.