Free tools
No signup, no account, nothing to install. Everything runs in your browser — none of what you type or select is transmitted anywhere.
What is recorded is anonymous, aggregate usage: which tool ran, and which multiple-choice options get picked. That’s it — no free-text input is collected because there are no free-text fields, and nothing identifies you. I use it to work out which failure modes are actually common, which is genuinely useful and which nobody has published.
If one of these keeps being useful, that’s usually a sign it’s worth a proper look at your system.
Why is my RAG hallucinating?
A free diagnostic for production RAG systems giving wrong, unsourced or fabricated answers. Answer what you're seeing, get a ranked list of likely root causes with the check that confirms each one.
LLM Cost Calculator
Compare per-request and monthly API costs across Claude, GPT, and Gemini models for your actual token usage.
Golden set size calculator
How many eval examples do you actually need to detect a regression? Enter your golden set size and find out the smallest accuracy drop it can reliably catch.