Brain

The agent's body is in the game, but its thinking comes from a large language model: the world it sees and the things you say are all handed to this model, the model decides what to do next, and the body carries it out. This model is its "brain".

You can give it a brain in the following ways:

• Model Setup: enter your own API key and call a model directly.
• External Brain: let an external agent drive it through MCP.

Model Setup

On the settings page of the panel, choose Model Setup and enter your own API key.

Numen natively supports both the OpenAI and the Anthropic API protocols and ships with presets for a number of model providers. Any provider not on the list works too, as long as it is compatible with one of the two protocols: just enter its address.

External Brain

Numen as a whole can act as an MCP server and be driven directly by an external agent, such as Claude Code, Codex, Cursor, or any other client that supports the MCP protocol.

Reasoning and token usage are then counted against the external agent, so you can drive Numen with the subscription plan of that client, which is usually cheaper than paying for API calls by usage.

On the settings page of the panel, choose External Brain and turn on the switch, then copy the connection prompt and send it to the external agent.