PromptDiff

compare prompt page
Prompt comparison page
See the last change prompt page
Home page where you can commit different prompts

Inspiration

The idea for PromptDiff came from the frustration of managing and testing LLM prompts. Even small changes in prompts can drastically affect outputs, yet there were no tools to track versions, compare differences, and test efficiently. So i create a tool that brings developer-friendly version control and clarity to prompt engineering.

What it does

It compare your prompt so you can check and testing which version of your code performing best.

How we built it

Frontend: React (for prompt editor, diff viewer, and output panel) Backend/API: Gemini LLM API (default) Database: Local storage for prompt history and versioning Features include:

Selecting any two versions of a prompt to compare
Side-by-side output comparison with token usage
Session-based BYO API key support

Challenges we ran into

Designing a clear, Git-like diff view for text prompts
Calculating token usage across multiple LLM outputs
Balancing feature scope with hackathon time constraints

Accomplishments that we're proud of

An clean and minimal UI/UX design
fast response

What we learned

Time management
How to handle api key and different work enviroment.
LLM prompt behavior and token usage
Versioning concepts similar to Git applied to text -Integrating AI APIs in a web environment