Start the server
golem serve
Golem listens on http://127.0.0.1:8743 and prints a token. Open that URL in a browser. The token is for extensions talking to the local API, not for the web UI.
Leave this process running.
Add a provider
Golem has no built-in model. Install a provider, then give it an API key. OpenRouter is a common first choice.
In another terminal:
golem extension add https://github.com/terracotta4u/golem-openrouter
export OPENROUTER_API_KEY=...
Stop the server (Ctrl+C) and run golem serve again so the new extension starts. The child process inherits OPENROUTER_API_KEY from your shell.
Default models in config already point at OpenRouter (openai/gpt-4o-mini for chat, openai/text-embedding-3-small for memory). You can change those later in Settings.
Chat
Open http://127.0.0.1:8743, type a message, and send it. If the provider is missing or the key is unset, the extension will fail to start or to answer; check the terminal where golem serve is running.