Butterfish
Butterfish adds AI assistance to your shell commands.
At a glance
Starts at
Free
No paid plan found on the vendor's site, September 2026.
Free tier
Yes
Platforms
macOS, Linux
Best for
Power users, developers
Not for
Users needing csh or fish shell support
3.9 out of 5
Scored by a Toolio reviewer after real useOur verdict
It enhances the command line experience with AI prompts and suggestions but requires an API key for setup.
✓What it does well
AI assistanceStart commands with a capital letter to get context-aware AI prompts.
Command history integrationThe AI considers your shell command history for more relevant suggestions and responses.
Autocomplete supportGPT suggests commands that you can complete with Tab, based on recent interactions.
✕Where it falls short
Manual API key setup requiredFirst use requires manual entry of an OpenAI API token.
Limited to bash and zshCurrently only works with bash and zsh, not other shell types like fish or csh.
No built-in model switching in UISwitching between models requires command-line configuration rather than a GUI.
Key features
CLI accessAccess through CLI, no web interface provided.
Customizable promptsEdit the prompt wrappers in ~/.config/butterfish/prompts.yaml for more control.
Goal mode executionUse goal mode to let an agent execute commands and reach a specified goal.
Configurable PromptsEdit prompt wrappers in configuration file.