razor

What is this?

You ask for a small query parser. The assistant reaches for a package, adds helper files, and leaves you more code to maintain. Razor asks whether the language or your project already has what the task needs.

It puts a short checklist before new code and uses targeted checks to prompt reconsideration of unnecessary additions. The aim is to finish the requested work with less to maintain. This example illustrates the workflow; the measurements below describe specific recorded runs.

Why you'd want it

• Reuse what the project already has.
• Reconsider unnecessary dependencies before installing them.
• Notice file growth before a small task becomes a larger project.
• Find declared dependencies that no source file appears to use.

How it works

A checklist asks whether the work is needed, already implemented or covered by the language. Targeted checks can request one reconsideration. A retry follows the host’s normal permissions. The unused-dependency audit reports findings without uninstalling anything.

What you can do

Send razor off or razor on to pause or resume the checks for the session; /razor off and /razor on also work in Claude Code. For a dependency report, use /razor:unused in Claude Code or select the installed unused skill in Codex.

Install

razor is one package for both hosts. Install it in the one you use.

Codex

Requirements: Node.js 22 or later, Git and a Codex host with plugin support.

codex plugin marketplace add V-Songbird/foundry
codex plugin add razor@foundry

Review and enable its hooks, then start a new Codex session.

Claude Code

Inside Claude Code:

/plugin marketplace add V-Songbird/foundry
/plugin install razor@foundry

Start a new session to load the plugin.

Good to know

Input validation, security and error handling that protects your work remain necessary. Explicitly requested scope stays yours to choose. These checks are advisory, not a security boundary.

File checks see the edits made through the assistant's own editing tool: apply_patch in Codex, Write and Edit in Claude Code. Files written by a shell command skip them, and so do unsupported or ambiguous patches in Codex. See setup and coverage and how razor works.

The numbers

Each result belongs to the named model and recorded run. Missing measurements remain marked as unmeasured.

Codex

Controlled Codex run at high reasoning on Windows: the table covers the full task group. Across all groups, razor passed 38/38 cases versus 29/38 without it. On jointly passing pairs, elapsed time was 1.8% higher and input tokens 0.8% higher; those measures did not improve. This exploratory result does not compare Sol against Claude.

Claude Code

A clean session completed the job without adding a package. Lines are averaged across the coding jobs. Mean session cost was $0.121 with razor, $0.155 without a plugin and $0.151 with ponytail. Blind comparisons did not establish better readability, and Sonnet cost savings did not reproduce reliably. These are recorded Claude results.

Results can vary between runs.

Original Claude Code benchmark visualization. These measurements describe the recorded Claude sessions, not Codex performance. Evidence and methodology.

Going deeper

How it works · Settings · Codex setup · Claude Code benchmark details · Codex benchmark harness

Foundry holds the research, methodology and detailed evidence for this plugin.

License

MIT — see LICENSE.