Stax is a tool from Google Labs to solve LLM evaluation. Move beyond "vibe testing" by building custom autoraters to measure what matters to you. It's a full toolkit for testing your AI stack with your data, with support for all major model providers.
Stax is one of the few products I've seen recently that got me genuinely excited. It tackles a core problem for anyone building with LLMs: how to objectively evaluate output quality beyond just "vibe testing." We've already started using it with my internal dev team.
It solves two major headaches right away. First, it integrates with all the major model providers, so you're not stuck building your own testing harnesses. Second, the way you can batch test across custom use cases is incredibly convenient.
One of my team members responsible for QA summed it up perfectly, and I quote:
"I wish I had this a few months ago!"
About Stax on Product Hunt
“Move your LLM evals from vibes to data”
Stax launched on Product Hunt on September 5th, 2025 and earned 182 upvotes and 4 comments, placing #5 on the daily leaderboard. Stax is a tool from Google Labs to solve LLM evaluation. Move beyond "vibe testing" by building custom autoraters to measure what matters to you. It's a full toolkit for testing your AI stack with your data, with support for all major model providers.
On the analytics side, Stax competes within A/B Testing, Developer Tools and Artificial Intelligence — topics that collectively have 997.5k followers on Product Hunt. The dashboard above tracks how Stax performed against the three products that launched closest to it on the same day.
Who hunted Stax?
Stax was hunted by Zac Zuo. A “hunter” on Product Hunt is the community member who submits a product to the platform — uploading the images, the link, and tagging the makers behind it. Hunters typically write the first comment explaining why a product is worth attention, and their followers are notified the moment they post. Around 79% of featured launches on Product Hunt are self-hunted by their makers, but a well-known hunter still acts as a signal of quality to the rest of the community. See the full all-time top hunters leaderboard to discover who is shaping the Product Hunt ecosystem.
Zac Zuo
Hi everyone!
Stax is one of the few products I've seen recently that got me genuinely excited. It tackles a core problem for anyone building with LLMs: how to objectively evaluate output quality beyond just "vibe testing." We've already started using it with my internal dev team.
It solves two major headaches right away. First, it integrates with all the major model providers, so you're not stuck building your own testing harnesses. Second, the way you can batch test across custom use cases is incredibly convenient.
One of my team members responsible for QA summed it up perfectly, and I quote: