Shannon

An AI-first shell built on nushell, with seamless bash compatibility and AI chat — all in one session.

Named after Claude Shannon, the father of information theory.

The Idea

Nobody remembers every shell command. Shannon lets you type in plain English and have an LLM translate your intent into the right command. When you need precise control, press Shift+Tab to drop into bash — then Shift+Tab back.

[nu] ~/project > ls | where size > 1mb
...
[nu] ~/project > <Shift+Tab>

[brush] ~/project > grep -r "TODO" src/
...
[brush] ~/project > <Shift+Tab>

[ai] ~/project > how do I find rust files modified today?
You can use `fd` or `find`:
  fd --extension rs --changed-within 1d

Features

AI Chat

Shift+Tab into [ai] mode — ask questions in plain English
Configurable provider (Anthropic by default)
Context-aware — the LLM knows your cwd and OS
Conversational — follow-up questions remember context

Nushell at the Core

Shannon IS nushell — you get all nushell features out of the box:

Structured data (tables, records, lists)
Powerful pipelines (ls | where size > 1mb | sort-by modified)
Job control (Ctrl+Z, job unfreeze)
Native completions, multiline editing, plugins
Hooks, keybindings, themes — all configurable via config.nu

Bash Compatibility

Shift+Tab to switch to [brush] mode for bash commands
Bash syntax highlighting (tree-sitter-bash, Tokyo Night colors)
Environment variables sync between nushell and bash automatically
env.sh for bash-style setup (PATH, API keys) — follow any tutorial that says "add this to your .bashrc"

Environment Sync

Environment variables, cwd, and exit code synchronized across mode switches
Set export FOO=bar in bash, switch to nushell — $env.FOO works
Set $env.BAZ = "qux" in nushell, switch to bash — echo $BAZ works
PATH and other typed env vars converted automatically via ENV_CONVERSIONS

Configuration

Shannon uses ~/.config/shannon/ (respects XDG_CONFIG_HOME):

File	Purpose
`env.sh`	Bash environment setup — PATH, env vars, API keys (runs first)
`env.nu`	Nushell env setup (runs after env.sh)
`config.nu`	Nushell config — keybindings, colors, hooks, completions
`history.sqlite3`	SQLite command history

No config files are required — shannon works out of the box.

Shannon-specific settings

Add to env.nu:

$env.SHANNON_CONFIG = {
    TOGGLE: ["nu", "brush", "ai"]
    AI_PROVIDER: "anthropic"
    AI_MODEL: "claude-sonnet-4-20250514"
    AI_API_KEY_ENV: "ANTHROPIC_API_KEY"
}

Installation

cargo install shannonshell

Or build from source:

git clone --recursive https://github.com/shannonshell/shannon.git
cd shannon/shannon
cargo build --release

Note: --recursive is needed to fetch the nushell, brush, and reedline submodules.

License

MIT

shannonshell 0.3.3