Plugin syntax errors are handled poorly #4850

Description

The Problem

Plugin syntax errors are handled poorly:

• Errors only show in stdout as raw JSON (not in UI)
• Error messages are unhelpful ("AggregateError: 2 errors" with no details)
• No indication in the UI that a plugin failed to load
• May crash with core dump in some cases

What Happened

While developing a plugin, a missing closing brace }; caused:

1. First attempt: OpenCode crashed with segmentation fault (core dump)
2. After restart: Same error now shows JSON to stdout, then OpenCode exits
3. Result: Very difficult to debug - had to watch terminal output

The Syntax Error

File: session-logger-broken.ts
Line: 91
Error: Missing closing brace for object literal

const example = {
  // ... properties
}, // ← Missing semicolon and closing brace here

examples.push(example); // ← This causes syntax error

What Should Happen

✅ Show error in the UI (toast notification or status bar)
✅ Display the actual syntax error with line number
✅ Show which plugin failed
✅ List loaded/failed plugins somewhere visible
✅ Never crash the main process

BUG_REPORT.md
session-logger-broken copy.ts.txt

OpenCode version

1.0.119

Steps to reproduce

1. Create a plugin file .opencode/plugin/session-logger-broken.ts
2. Copy the contents of the attached session-logger-broken copy.ts.txt file (contains syntax error - missing closing brace)
3. Start OpenCode with opencode command
4. Current Result: JSON error printed to stdout, OpenCode exits
5. To see the error: Check stdout/terminal output for JSON error message
6. Previous Result (in same terminal window but different tab): OpenCode would crash with segmentation fault

See my comment below with a script that reliably causes opencode to dump core.

session-logger-broken copy.ts.txt

Screenshot and/or share link

No TUI ever appeared, I got this on stdout instead and opencode terminated:

{
"name": "UnknownError",
"data": {
"message": "AggregateError: 2 errors building "/home/alan/opencode-dspy/.opencode/plugin/session-logger-broken.ts"\n at requestFetch (native:1:11)\n at (native:11:43)\n at (native:11:37)\n at requestInstantiate (native:1:11)\n at requestSatisfyUtil (native:1:11)\n at requestSatisfy (native:1:11)\n at requestImportModule (native:2)\n at requestImportModule (native:1:17)\n at (src/plugin/index.ts:42:32)\n at processTicksAndRejections (native:7:39)"
}
}

Operating System

Ubuntu 22.04

Terminal

kitty