[FEATURE] Native Nushell (nu) Tool Support in Claude Code

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Hi Anthropic Team,

I'd like to submit a feature request based on benchmarking I conducted with Claude Code.

---

Request: Add Native Nushell Tool to Claude Code

Current situation:
Claude Code only has a Bash tool for shell execution. To use Nushell, agents must wrap every command via:

"/c/Program Files/nu/bin/nu.exe" -c "<nushell command>"

This creates several friction points:

• Escaping hell bash parses $() before nu does, causing interpolation bugs
• Table output gets swallowed by bash stdout capture
• Higher retry rates (6x on HTTP tasks, 8x on complex pipelines)
• LLM has to mentally juggle two shell syntaxes simultaneously

---

Benchmark Results (PowerShell vs Nushell, 7 tasks)

| Metric | PowerShell | Nushell |
|---|---|---|
| Task wins | 2 | 5 |
| Avg readability | 6.5/10 | 8.75/10 |
| Avg command length | ~175 chars | ~145 chars |
| Output quality | 6/10 | 9.5/10 |

Nushell won on output quality, readability, and token efficiency but lost on first-try reliability due entirely to the bash wrapper overhead.

---

Proposed Solution

Proposed Solution

Add a native Nu tool in Claude Code alongside the existing Bash tool:

// Conceptual tool addition
{
  "tool": "Nu",
  "description": "Execute Nushell commands natively",
  "input": { "command": "string" }
}

Estimated impact if implemented:

• Retry rate reduction: ~60-70% on complex tasks
• Escaping issues: eliminated
• Output quality: consistent structured tables
• Token usage: more efficient (shorter commands)

---

Why This Matters for LLM Agents

Nushell's structured-data-first philosophy is philosophically aligned with how LLMs work best output as typed tables rather than plaintext strings means agents can act on data directly without secondary parsing. The bash wrapper currently negates this advantage.

Thank you for considering this!

Alternative Solutions

_No response_

Priority

High - Significant impact on productivity

Feature Category

Performance and speed

Use Case Example

_No response_

Additional Context

This is NOT a duplicate of #4535.

#4535 is a bug report about Claude Code injecting < /dev/null
into Nushell pipelines on Linux.

This is a feature request to add a native Nu tool in Claude Code
to eliminate bash wrapper limitations entirely — which would also
resolve #4535 as a side effect.

Different platform (Windows), different angle, different solution requested.
Please keep open. 👎