nupi 🐘π

A Pi Coding Agent extension that replaces the built-in bash tool with Nushell (nu).

What it does

Registers a tool named bash (displayed as nushell in the TUI) that executes scripts using nu instead of bash. The agent gets full Nushell language support — structured pipelines, open, http get, | where, | get, | to json, | to nuon, etc. — including native nuon (Nushell Object Notation) for structured data interchange.

Requirements

• Node.js with ES2022+ support
• Nushell installed with nu in your PATH
• @mariozechner/pi-coding-agent

Installation

pi install git:github.com/kiil/nupi

Remember to create a pi.nu in your nushell config dir (~/.config/nushell/pi.nu) and source custom commands and use modules you want available on pi.

Bonus:

You can use this in your pi config if you additionally want nushell for the ! and !! functionality in pi:

  "shellPath": "/path/to/your/nu",

You can even set nushell up to output nuon instead of the standard table. To make the output digestable and token effective for the coding agent and underlying LLM.

Add this in your pi.nu.

$env.config = {
  # ... dine andre indstillinger
  hooks: {
    display_output: {
      if ($in | describe | str contains "table") or ($in | describe | str contains "list") or ($in | describe | str contains "record") {
        $in | to nuon --indent 2  # Her tvinger vi NUON i stedet for tabel
      } else {
        table # Hvis det er noget andet, så brug standard tabel-visning
      }
    }
  }
}

Unfortunately, there is currently no clean way to make this work for the ! and !! functionality automatically as the shellPath config option does not accept arguments and there currently does not seem to be another option for setting arguments.

You can of course always do this:

!command | to nuon (to get the output into the context)

or this

!!command | to nuon (to leave output out of context)

Behavior

• Scripts are written to a temp file (pi-nu-*.nu) before execution to avoid quoting issues with multi-line scripts and special characters.
• Output is capped at 2000 lines or 50 KB, whichever comes first — matching Pi's default bash limit.
• Partial output is streamed to the TUI in real time.
• Default timeout is 30 seconds (overridable per call).
• Nushell is spawned with --config ~/.config/nushell/pi.nu - make sure to source your custom commands and use modules you need from a pi.nu file in that location.
• Temp files are cleaned up after each run, even on error or timeout.