feat: Muse Spark in opencode via Muse Code subscription device login

Author: TheStreamCode

.github/workflows/ci.yml

@@ -0,0 +1,17 @@
+name: ci
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  build-test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: "24"
+      - run: npm install
+      - run: npm run build
+      - run: npm test

.gitignore

@@ -0,0 +1,3 @@
+node_modules/
+dist/
+*.tsbuildinfo

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 TheStreamCode
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

NOTICE

@@ -0,0 +1,5 @@
+Flow parameters compatible with the published behavior of oh-my-pi
+(https://github.com/can1357/oh-my-pi), MIT-licensed (c) 2025 Mario Zechner,
+(c) 2025-2026 Can Bölük, (c) 2026 Stencil Labs, Inc. No oh-my-pi code is
+vendored here; the device-code exchange is an independent implementation.
+No oh-my-pi branding appears in the user experience.

README.md

@@ -0,0 +1,53 @@
+# opencode-muse-auth
+
+Use Meta **Muse Spark** in [opencode](https://opencode.ai) billed to your
+**Muse Code monthly subscription** — no pay-as-you-go API key, no third-party CLI.
+
+## Install
+
+```jsonc
+// opencode.json
+{
+  "$schema": "https://opencode.ai/config.json",
+  "plugin": ["opencode-muse-auth"]
+}
+```
+
+Then run `/connect` in opencode, pick the `meta` provider and the
+*Muse Code subscription* method: it shows a Meta device page URL and a code.
+Enter the code in your browser (your own Meta account) and the login
+completes by itself.
+
+## Requirements
+
+- opencode with plugin support
+- A Meta account with an active Muse Code subscription
+
+## How it works
+
+The plugin registers an `auth` hook for the built-in `meta` provider
+(Routes through the Responses API, `meta.txt` system prompt applies
+automatically to `muse-*` model ids):
+
+- **Login** — Meta device-code exchange (RFC 8628) inside `/connect`, then
+  mints the stable account-bound inference key via the Model API. The key is
+  cached locally (`~/.config/opencode/muse-code-sub.json`, owner-only
+  permissions where supported) and never printed.
+- **Runtime** — an auth `loader` injects the cached key on every startup.
+  The mint endpoint is aggressively rate-limited, so the plugin never
+  re-mints on its own; re-run `/connect` only if access is revoked (401).
+
+Flow parameters are compatible with the published behavior of oh-my-pi (MIT);
+see [NOTICE](NOTICE).
+
+## Development
+
+```sh
+npm install
+npm run build
+npm test
+```
+
+## License
+
+MIT — see [LICENSE](LICENSE).