prerequisites

Before installing kasmos, make sure you have the required tools and at least one supported AI agent CLI.

required

tool	purpose	install
tmux	session management for agent instances	tmux wiki
gh	GitHub CLI for PR creation and auth	cli.github.com

Both are required — kasmos will not function correctly without them.

supported AI harnesses

kasmos auto-detects installed AI CLIs during kas setup. The setup wizard currently probes for three harnesses natively:

harness	CLI	detection
opencode	opencode	auto-detected
claude	claude	auto-detected
codex	codex	auto-detected

The following CLIs are supported at runtime (kasmos can spawn them) but are not auto-detected by the wizard's built-in registry:

• Gemini CLI — gemini
• Amp — amp
• Aider — aider

You need at least one AI harness installed. Having multiple harnesses allows you to assign different roles (planner, coder, reviewer) to different CLIs.

unsupported or custom harnesses

If you use a harness that the wizard doesn't detect, you can still wire it up manually:

1. Run kas setup and select a supported harness as a placeholder
2. Edit .kasmos/config.toml (repo-relative) after the wizard completes
3. Set program to the exact command string (including any flags) for your CLI

[agents.coder]
enabled = true
program = "aider --model gpt-4o"
execution_mode = "tmux"

Custom programs run in tmux mode — the sdk backend is only available for claude and codex.

See setup wizard for the full config schema.

Go version

If you are building from source or using go install, Go 1.24 or later is required.