Chatter

Acquired

Dead simple LLM testing and iteration

Y Combinator S23

What it does

Chatter is Postman for LLMs. Our platform helps companies and developers test their LLM models. Iterate on prompts, run them across model families and evaluate them against test cases – all in one place. With collaboration features, engineers can design LLM chains while QA can write test cases.

Its site says now · captured 2026-08-23

Chatter | LLM testing platform

Chatter lets anyone in your team iterate on and test your LLM prompts and chains, giving you faster iteration cycles and more reliable products.

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