Desktop v1.18.9: npm plugin install still fails with @opencode-ai/plugin@local (regression of #26085)

[godboss-lab]

Description

OpenCode Desktop v1.18.9 (Windows 11, Electron) still fails to load npm plugins. The sidecar resolves @opencode-ai/plugin peer dependency as @local, which does not exist in the npm registry, causing NpmInstallFailedError. Plugins registered in ~/.config/opencode/opencode.json never load — no agents, no hooks, no tools from plugins.

This appears to be a regression or incomplete fix of #26085 (closed).

Environment

• OpenCode Desktop: v1.18.9 (packaged: true)
• OS: Windows 11
• Plugin: oh-my-openagent@latest (v4.19.3+)
• Config location: ~/.config/opencode/opencode.json

Reproduction

1. Install OpenCode Desktop v1.18.9
2. Add to ~/.config/opencode/opencode.json:

   {
     "plugin": ["oh-my-openagent@latest"]
   }

3. Launch Desktop
4. Observe: only native build and plan agents available; no plugin agents (Sisyphus, etc.)

Error Log

From ~/.local/share/opencode/log/opencode.log:

timestamp=2026-07-29T15:16:33.344Z level=WARN run=da74ead9 message="background dependency install failed" dir="C:\\Users\\godboss\\.config\\opencode" error="Cause([Fail(NpmInstallFailedError (cause: @opencode-ai/plugin: No matching version found for @opencode-ai/plugin@local.))])"

The sidecar spawns successfully (sidecar connection started { version: 'v1' }) and the server is ready, but the plugin npm install fails silently (only a WARN log, no user-facing error).

Expected Behavior

Plugins listed in opencode.json should load correctly. If install fails, the error should be surfaced to the user (toast/dialog), not silently swallowed.

Workaround

Side-load the plugin via the ~/.config/opencode/plugins/ directory, which bypasses the npm install entirely:

// ~/.config/opencode/plugins/omo-loader.js
import plugin from "oh-my-openagent";
export default plugin;

This works because OpenCode auto-discovers JS files in the plugins/ directory and the package is already present in ~/.config/opencode/node_modules/.

Related

• Electron sidecar: npm plugins fail to load — peer dep @opencode-ai/plugin resolves as @local #26085 (closed) — same root cause, reportedly fixed
• Desktop App is not pickuping opencode.json project configuration file #30725 — Desktop not picking up project config (related but different scope)
• [Question]: installed OMO, reopen opencode can not find Sisyphus in agents , only select plan or build code-yeongyu/oh-my-openagent#3456 — downstream report of missing agents
• OpenCode Desktop shows oh-my-openagent as loaded, but only native build/plan modes are available code-yeongyu/oh-my-openagent#5025 — downstream known-issue + workaround docs

[github-actions]

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

• [Bug] Startup Warning: NpmInstallFailedError for @opencode-ai/plugin@local #37024: Same NpmInstallFailedError for @opencode-ai/plugin@local startup warning
• opencode desktop(windows) load superpowers failed because of fails to load plugins: tries to install @opencode-ai/plugin@local, which is not a published npm version #38271: Same root cause on Windows — Desktop tries to install @opencode-ai/plugin@local which is not a published npm version
• Background "npm install @opencode-ai/plugin@local" fails on every project dir — OPENCODE_VERSION not injected in packaged build (Desktop v1.18.1) #37806: @opencode-ai/plugin@local fails because OPENCODE_VERSION is not injected in packaged Desktop builds
• Server: background dependency install fails every session with @opencode-ai/plugin@local not found #30908: background dependency install fails every session with @opencode-ai/plugin@local not found
• Desktop app hangs on Windows 11 - @opencode-ai/plugin@local npm install failed #31708: Desktop app hangs on Windows 11 due to the same @opencode-ai/plugin@local npm install failure
• Desktop: background dependency install failed - @opencode-ai/plugin@local version not found #30197: Desktop: background dependency install failed — @opencode-ai/plugin@local version not found

If your issue is the same underlying problem, please consider adding a +1 or additional context to one of those existing reports rather than opening a new one.