SanityCheck

What it does

Stop building in the dark. Stop asking your mom if your startup idea is good. Stop guessing whether people want what you're about to spend 3 months building (or 3 days vibe coding). I made a fix: SanityCheck.dev You post your idea. The internet tells you the truth. You get real signals, not optimism bias. If you’re brave enough, submit your idea: sanitycheck.dev

Add a URL, describe your test in a sentence or two, and run. AI agents open real browsers and test your app like an actual user. Watch live, replay every click, trigger on every GitHub, GitLab, or Vercel deploy. Free tier included.

UI/UX testing, automated. Describe how you want your agent to test. That's it. Watch one or more AI agents spin up real browsers and test your app like an actual user. No SDK, no CI config, no test framework. If you can describe what a user should be able to do, you can test it. Paste a URL. Add test credentials, always encrypted and never provided to the agent, plus rules for what the agent may and may never do. “Add a contact and verify it appears in the list.” A sentence or two is the whole test. No selectors, no scripts, no framework. A real agent spins up a real browser in the cloud and clicks through your app like an actual user. Watch any session live, then replay every step.…from sanitycheck.dev

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