`import.meta.resolve(dir)` one-arg form returns directory URL on Node.js, causing custom npm providers to fail with `ERR_UNSUPPORTED_DIR_IMPORT`

Summary

Custom npm providers configured via the npm field in opencode.jsonc fail to initialize in OpenCode's TUI/server mode when running on Node.js, while the same configuration works in the CLI (Bun). The root cause is an asymmetry in import.meta.resolve() between Bun and Node.js in packages/core/src/npm.ts.

Environment

• OpenCode: v1.18.25
• Runtime: Node.js v24.14.0 (also affects Electron/Desktop)
• OS: Windows 10

Symptom

When a custom provider is configured via npm package name:

{
  "plugin": ["opencode-cmd-provider"],
  "provider": {
    "commandcode": {
      "npm": "opencode-cmd-provider",
      "name": "Command Code",
      "options": {
        "apiKey": "..."
      }
    }
  }
}

• opencode models commandcode — works ✅
• opencode run -m commandcode/deepseek/deepseek-v4-flash "hello" — works ✅
• Interactive TUI — fails with Failed to initialize provider: commandcode ❌

Using file:// URL directly to the dist entry file fixes all modes:

"npm": "file:///absolute/path/to/opencode-cmd-provider/dist/index.js"

Root Cause

In packages/core/src/npm.ts, the resolveEntryPoint function handles Bun and Node.js differently:

const resolveEntryPoint = (name: string, dir: string): EntryPoint => {
  let entrypoint: Option.Option<string>
  try {
    const resolved = typeof Bun !== "undefined"
      ? import.meta.resolve(name, dir)   // ✅ Bun: resolves to entry file
      : import.meta.resolve(dir)          // ❌ Node: returns directory URL
    entrypoint = Option.some(resolved)
  } catch {
    entrypoint = Option.none()
  }
  return { directory: dir, entrypoint }
}

• Bun path: import.meta.resolve(name, dir) — correctly resolves the package name relative to the directory, returning the actual entry file (e.g., file:///.../dist/index.js)
• Node path: import.meta.resolve(dir) — merely converts the directory path to a file:// URL

The caller then does await import(importSpec) with the resolved path. Node.js ESM does not support import() of a directory URL — it throws ERR_UNSUPPORTED_DIR_IMPORT regardless of what package.json declares in main/exports.

This explains why:

• CLI commands (run, models) work — they may use a cached/loaded SDK or a different resolution path
• TUI/server fails — it freshly initializes providers via Npm.add() and hits the directory import error
• file:// works — it bypasses npm resolution entirely, passing the exact file path to import()

Fix

Both Bun and Node.js 20.6+ support the two-argument form of import.meta.resolve(name, dir). The fix is to use it consistently:

const resolveEntryPoint = (name: string, dir: string): EntryPoint => {
  let entrypoint: Option.Option<string>
  try {
-   const resolved = typeof Bun !== "undefined"
-     ? import.meta.resolve(name, dir)
-     : import.meta.resolve(dir)
+   const resolved = import.meta.resolve(name, dir)
    entrypoint = Option.some(resolved)
  } catch {
    entrypoint = Option.none()
  }
  return { directory: dir, entrypoint }
}

Related

• PR #44722 — Alternative approach that resolves entry from manifest (exports → module → main → index.js) instead of fixing the import.meta.resolve call
• PR #32060 — Earlier attempt (auto-closed by stale bot)
• Issue #31909 — Original bug report for Desktop/Electron
• Issue rashidrazak/opencode-cmd-provider#102 — Downstream plugin report documenting the file:// workaround