Why does the Brain say a coding agent is not installed?

The Brain needs an installed coding agent, but it does not require Claude specifically. If the selected provider says not installed or isn't available, install that provider or choose another installed one from the selector at the bottom of the Brain.

Before you start

Your Codus sign-in does not install or sign you in to Claude, Codex or another provider. Use the provider you intend to run, with its own account and access.

Check the selected provider

1. Open the Brain and its provider selector. Opening the selector checks availability.
2. Choose an installed provider. An unavailable option is disabled.
3. If none is installed, use the provider's install button. Follow Claude Code setup or Codex setup.
4. Open a new Terminal on Mac or PowerShell on Windows and run claude --version or codex --version. This checks whether your computer can find that program.
5. If it is found there but not in Codus, finish any active work, quit Codus fully and reopen it. Newly installed commands may not be available to an app that was already running.

On Windows, a program installed only inside WSL is not the same as a program available to the Windows PowerShell session. Use the installation instructions for the environment Codus is running.

If it asks you to sign in instead

Sign in on launch is different from not installed. The program exists but its own sign-in must be completed. Approve the correct provider account in the browser and return to the session. Do not paste passwords or sign-in tokens into support chat.

How do I know it worked?

The provider no longer shows not installed, and its Brain session opens and answers your message.