Muse Code OpenRouter

Use an OpenRouter API key and model directly inside Meta Muse Code. After setup, the normal muse command uses meta/muse-spark-1.2 through OpenRouter; no Codex configuration is involved.

Why an adapter is needed

Muse Code 0.2.1 exposes a --base-url option but the shipped binary only enables its meta and echo providers. Pointing that Meta provider straight at OpenRouter fails before inference because Muse first requests the proprietary /muse-code/models catalog. Muse also requires a sequence_number on each Responses API stream event, which compatible providers do not always emit.

The local adapter fixes those protocol differences:

• translates OpenRouter's public model record into Muse's local model catalog;
• replaces Muse's endpoint with a loopback-only Responses API adapter;
• supplies the OpenRouter credential without putting it in Muse's Meta auth store;
• adds missing stream sequence numbers; and
• shortens and restores provider-incompatible function names when necessary.

Install

curl -LsSf https://xhluca.github.io/muse-code-openrouter/install.sh | sh

The installer installs Meta's official Muse Code launcher if muse is missing, installs this package for the current user, and prompts for the OpenRouter key without echoing it. Afterwards, use Muse Code normally:

muse

Manual installation is also supported:

uv tool install muse-code-openrouter
muse-openrouter setup
muse-openrouter doctor --live

For automation, supply the key on standard input so it does not appear in shell history or the process list:

printf '%s\n' "$OPENROUTER_API_KEY" | muse-openrouter setup --key-stdin

What setup changes

• Stores the key at ${XDG_CONFIG_HOME:-~/.config}/muse-code-openrouter/credential, mode 0600.
• Preserves Muse's other settings while updating provider, model, endpoint_transport, and model_catalog in ~/.config/muse/settings.json.
• Saves the original Muse settings under ${XDG_STATE_HOME:-~/.local/state}/muse-code-openrouter/.
• Starts a loopback-only adapter on 127.0.0.1:8817, normally as a systemd user service on Linux.

The adapter never logs API keys, authorization headers, prompts, request bodies, or model responses. Muse session logging remains controlled by Muse itself.

Development

uv run --with pytest pytest
uv run --with ruff ruff check .
uv build

The adapter is dependency-free Python and supports Linux and macOS. The service installer uses systemd when available and otherwise launches a detached process.