BUILDMID

Build a Prompt Engineering Playground

60 minutes

0 completed

nextjsaiprompt-engineeringfullstack

Description

Build a tool to test, compare, and iterate on AI prompts with side-by-side output comparison.

Requirements

Prompt editor with variables support ({{name}}, {{context}}, etc.)

Variable input panel to fill in template variables

Send prompt to a mock AI endpoint (simulate responses with delay)

Side-by-side comparison: run 2 prompt variants simultaneously

Token count estimator (approximate based on word count x 1.3)

Prompt history with timestamps and outputs

Save favorite prompts with names and tags

Build a clean prompt template system. For the mock API, create a Next.js API route that returns simulated responses.

Real API integration (OpenAI/Anthropic) with key input

A/B test mode comparing prompt performance

Export prompt library as JSON

You will be guided through MCP setup before the timer starts