opencode-muse-auth

Muse Code subscription sign-in for opencode

opencode plugin that registers the Muse Code subscription login method for the built-in meta provider, so Meta Muse Spark is billed to a Muse Code monthly subscription instead of per-token API credits. No API key to copy and no third-party CLI to install.

Unofficial and experimental. This plugin uses a Muse Code subscription credential from opencode. Meta's terms limit that credential to Muse Code, so this use may not be supported and Meta may suspend or revoke accounts or credentials. Use it at your own risk; the authors cannot recover an account. Read DISCLAIMER.md before installing.

Install

Add the plugin to opencode.json; opencode installs it from npm:

// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "plugins": ["opencode-muse-auth"]
}

Sign in

1. Run /connect in opencode.
2. Pick the meta provider and the Muse Code subscription method.
3. Open the printed Meta device page, enter the printed code, and approve the login in your own browser. The login completes by itself.
4. Select a muse-* model exposed by the meta provider, for example meta/muse-spark-1.3.

The plugin mints a stable, account-bound inference key and hands it to opencode. The OAuth access token from the login flow is kept in memory only and is never written to disk.

Features

• Registers an auth hook for the built-in meta provider; there is no separate provider id to configure.
• Runs the Meta device-code exchange (RFC 8628) inside /connect, then mints the subscription inference key through the Model API.
• Routes through the Responses API; the meta.txt system prompt applies automatically to muse-* model ids.
• V1 storage: the OpenCode auth store is the primary source, and the loader falls back to the legacy cache only when the store has no key.
• V2 storage: the credential lives in the OpenCode integration store, and no local cache is written on this path.
• Never re-mints on its own; re-run /connect only after a 401, because the mint endpoint is aggressively rate-limited.
• Flow parameters are compatible with the published behavior of oh-my-pi (MIT); see NOTICE and AUTH_CONTRACT.md.

Requirements

• opencode with plugin support, including the v2 plugin module shape accepted by opencode 1.18.29+ and 2.x.
• Node.js 22.6 or newer for development; CI runs Node.js 22 and 24.
• An active Muse Code subscription on the Meta account used at login.

Configuration

Setting	Purpose	Default
plugins entry in opencode.json	Loads the plugin.	not set
Auth store	Primary credential storage used by the V1 loader.	~/.local/share/opencode/auth.json
Legacy cache	Read-only fallback for credentials written by earlier versions.	~/.config/opencode/muse-code-sub.json
/connect method	Selects Muse Code subscription login for the meta provider.	meta provider

Privacy and security

The inference key is held by opencode: in the V1 auth store or the V2 integration store. The legacy cache, when present, stores only apiKey, accountId, and email; the OAuth access token is never written to disk. The plugin talks only to auth.meta.com for the device login and api.meta.ai for key minting and inference. See SECURITY.md for vulnerability reporting.

To remove access:

• disconnect the provider or log out in opencode (the store is ~/.local/share/opencode/auth.json);
• delete ~/.config/opencode/muse-code-sub.json if an older version created it;
• run muse logout if you also want to clear the Muse Code CLI session;
• remove opencode-muse-auth from opencode.json.

Troubleshooting

/connect shows no Muse Code subscription method

The plugin is not loaded. Check the JSON syntax of opencode.json, the plugin name spelling, and the package installation, then restart opencode.

Requests fail with 401 or access was revoked

The key was rotated or revoked. Re-run /connect once; the plugin never re-mints on its own.

The login times out or is denied

Approve the printed code in the browser before the flow expires, then retry. A login rejected by Meta usually means the account has no active Muse Code subscription.

A legacy cache file is still present

It is harmless: the V1 loader prefers the OpenCode auth store and reads the cache only when the store has no key. Delete the file if you are migrating to V2 storage.

Development

Requirements: Node.js 22.6 or newer and npm.

git clone https://github.com/TheStreamCode/opencode-muse-auth.git
cd opencode-muse-auth
npm install
npm run build
npm test

npm test builds with tsc and runs the TypeScript test suite with the Node test runner. CI runs the same gate on Node.js 22 and 24; Node 22 needs 22.6 or newer for test-runner type stripping. No Meta account is needed for the test suite.

Support

Usage questions and workflows belong in GitHub Discussions; reproducible defects belong in GitHub Issues using the bug report form. See SUPPORT.md. Problems in opencode or Meta themselves belong to their respective projects.

Contributing

See CONTRIBUTING.md. Pull requests must pass the required CI checks.

License

MIT — see LICENSE. The software is provided "as is"; see DISCLAIMER.md for the risk notice and liability terms.

---

Maintained by Michael Gasperini (Mikesoft). If this project is useful to you, consider sponsoring its maintenance.