OopsGPT — Regression tests for prompts before they embarrass a business

A ‘prompt regression test’ service for small businesses that have built an AI workflow in ChatGPT, Zapier, Make, or an LLM API. The user stores a prompt, a small set of representative inputs, and expected qualities such as “must mention price,” “never invent a policy,” or “output valid JSON.” On a schedule or after a prompt edit, the tool runs tests and flags output changes, formatting failures, forbidden claims, and overly similar canned responses. The creative niche is serving non-technical AI automators who are increasingly relying on fragile prompts but do not know how to test them. Day 1 MVP can avoid paid model calls entirely: accept pasted before/after outputs and run deterministic checks—JSON validation, regex/policy rules, similarity scoring, length checks, and diff reports. Later, users bring their own API key for automated runs. Build with FastAPI or Streamlit, SQLite/Supabase, and free deployment; use GitHub Actions for scheduled tests. Offer a free manual comparison tool and charge $12–39/month for saved suites, webhook/email alerts, and scheduled bring-your-own-key runs. It leverages an ML engineer’s evaluation knowledge while keeping marginal costs near zero.