Windows: OpenCode fails to start - Cannot find module '@openauthjs/openauth/pkce'

[jqbdyhz]

Description

When running opencode-cli.exe auth login on Windows, selecting "OpenCode Zen" provider causes an error:

error: Cannot find module '@openauthjs/openauth/pkce' from 'C:\Users\...\.cache\opencode\node_modules\opencode-anthropic-auth\index.mjs'

Root Cause

The @openauthjs/openauth package (version 0.4.3) has an incomplete npm release:

• package.json declares exports: "./*": { "import": "./dist/esm/*.js" }
• But the dist/esm/ directory does not exist in the published package
• Only dist/types/ and src/ are present

When opencode-anthropic-auth tries to import from @openauthjs/openauth/pkce, module resolution fails.

Environment

• OS: Windows 11 x64
• OpenCode CLI version: 1.0.164 (from desktop installer at D:\OpenCode)
• Also reproduced with pnpm-installed opencode-ai@1.1.2

Workaround

Manually create the missing file at:
~/.cache/opencode/node_modules/@openauthjs/openauth/dist/esm/pkce.js

With a self-contained PKCE implementation (base64url encode + SHA-256 challenge generation).

Suggested Fix

Either:

1. Pin @openauthjs/openauth to a version that includes dist/esm/ in the published package
2. Or update opencode-anthropic-auth to use a different import path that exists

---

🤖 Generated with Claude Code

[github-actions]

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

• Installation fails on Fedora 43 with npm after version v1.0.152 #5604: Installation fails on Fedora 43 with npm after version v1.0.152 - Similar missing module issues during installation
• Cannot build Open-Code due to missing @tsconfig/bun dependency #4127: Cannot build OpenCode due to missing @tsconfig/bun dependency - Related module resolution issues
• Docker container fails to start due to bun dependency install issue #4774: Docker container fails to start due to bun dependency install issue - Similar @openauthjs/openauth problems in containerized environments
• Github Enterprise authorization #3936: Github Enterprise authorization - Related authentication module failures

Additionally, since this issue involves authentication keybinds and the auth login command, please check our pinned keybinds documentation: #4997

[jqbdyhz]

Thanks for the auto-detection! I checked the related issues but this appears to be a distinct problem:

This is NOT a network/installation race condition - the package @openauthjs/openauth@0.4.3 is successfully downloaded, but its published npm tarball is missing the dist/esm/ directory entirely.

Evidence:

• package.json declares: "./*": { "import": "./dist/esm/*.js" }
• But only dist/types/ and src/ exist in the installed package
• The src/pkce.ts source file exists, but no compiled dist/esm/pkce.js

This means the upstream package was published without running the build step, so the compiled ESM output is missing.

Workaround confirmed working: manually create ~/.cache/opencode/node_modules/@openauthjs/openauth/dist/esm/pkce.js with a self-contained PKCE implementation.

[jqbdyhz]

Update: Issue persists in v1.1.2 (Desktop App & CLI)

Just tested with a fresh install of v1.1.2 (both Desktop App and pnpm-installed CLI) - the issue still occurs.

Why the workaround keeps disappearing

After applying the workaround, OpenCode works fine. But the fix gets lost when:

1. OpenCode auto-updates - dependencies are re-downloaded, overwriting the manually created pkce.js
2. Cache rebuild - OpenCode sometimes rebuilds .cache/opencode/node_modules/
3. System cleanup tools - tools like CCleaner may clean .cache directories

One-liner fix (PowerShell)

For anyone hitting this on Windows, here's a quick fix:

$d = "$env:USERPROFILE\.cache\opencode\node_modules\@openauthjs\openauth\dist\esm"; New-Item -ItemType Directory -Force -Path $d | Out-Null; @'
function base64UrlEncode(buffer) { const bytes = new Uint8Array(buffer); let binary = ""; for (let i = 0; i < bytes.byteLength; i++) binary += String.fromCharCode(bytes[i]); return btoa(binary).replace(/\+/g, "-").replace(/\//g, "_").replace(/=+$/, ""); }
export async function generatePKCE() { const verifierBytes = new Uint8Array(32); crypto.getRandomValues(verifierBytes); const verifier = base64UrlEncode(verifierBytes); const encoder = new TextEncoder(); const data = encoder.encode(verifier); const hash = await crypto.subtle.digest("SHA-256", data); const challenge = base64UrlEncode(hash); return { verifier, challenge, method: "S256" }; }
export function createChallenge(verifier) { const encoder = new TextEncoder(); const data = encoder.encode(verifier); return crypto.subtle.digest("SHA-256", data).then(base64UrlEncode); }
'@ | Set-Content "$d\pkce.js" -Encoding UTF8; Write-Host "Fixed!"

Suggested permanent fix

The real fix should happen upstream - either:

1. @openauthjs/openauth publishes a version with dist/esm/ included
2. Or OpenCode pins to a working version / uses a different import path

---

🤖 Generated with Claude Code