I made a JSFiddle-style playground to test and share prompts fast

In plain words

This is a browser-based prompt testing playground designed for AI developers and teams. It allows users to test and share prompts with variables and Jinja2 templates across different models without requiring signup, API keys, or complex setup. The tool emphasizes simplicity and speed, letting users experiment immediately by opening a URL and share results with teammates, similar to how JSFiddle works for code.

written from the facts on this page · September 2026

From the sources

In the maker’s words, at launch

I built this out of frustration as I lead the development of AI features at Yola.com. Prompt testing should be simple and straightforward. All I wanted was a simple way to test prompts with variables and jinja2 templates across different models, ideally somthing I could open during a call, run few tests, and share…

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