Whetstone.

The definitive prompt-engineering workspace. Rough idea in, precision prompt out — across Claude, GPT, and Gemini.

Client

Whetstone

Website

whetstone-prompt.online ↗

Timeline

8 weeks

Team

2 engineers, 1 designer

Scope

Design, Engineering, Launch

Whetstone came to Kleta with a clear vision: build the definitive workspace for prompt engineering. Teams were drowning in scattered prompt docs, losing track of what worked, and wasting hours on manual iteration.

We designed and shipped a complete platform — from AI-powered refinement to folder-based organization — in eight focused weeks. The result is a tool that turns rough ideas into precision prompts.

Four systems, one coherent product.

/01

Multi-model refinement engine

AI-powered prompt optimization across Claude, GPT, and Gemini. Brain dump a rough idea, answer a few questions, get a precision prompt. The engine stress-tests and sharpens — not just rewrites.

/02

Premium dark interface

A bold, typographic design system built for focus. Every pixel tuned for long prompt-writing sessions with zero visual fatigue. Dark-first because prompt engineers live in terminals.

/03

Prompt management system

Folders, tags, and instant search. Organize hundreds of prompts with a system that scales from solo users to engineering teams. Never lose a working prompt again.

/04

Collaboration & reuse

Copy, reuse, and iterate on your best prompts instantly. Shared workspaces with version history so teams can build on each other's best work.

Measurable impact.

0^×

Better outputs

0^×

Faster iteration

∞

Reusable prompts

Start with the loop. Build from there.

We started with the core loop: write a rough prompt, refine it with AI, save it for reuse. Everything else grew from that single interaction.

The refinement engine queries multiple models to stress-test and sharpen prompts — not just rewrite them. We built a three-step flow: Brain Dump your rough idea, Smart Refine with guided questions, then arrive at a Gold Standard prompt.

The interface was designed dark-first because prompt engineers live in terminals and code editors. We matched that energy with a system that feels native to their workflow — fast, keyboard-friendly, and visually quiet.

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