Why we ship eval suites with every agent
A working AI feature without an eval is a magic trick. The trick stops working the moment the model behind it changes.
You did not build the model. You will not control when it changes. Anthropic, OpenAI, and Google ship updates on their own schedule, and the model you tested on Tuesday is not the model your users hit on Wednesday.
An eval suite is the only way to tell whether the latest provider update made your product better, worse, or the same. Without one, you are flying blind.
We build evals before we ship. Golden cases for the happy path, adversarial cases for the failure modes you noticed in the first week, and a regression set that grows every time something breaks.
The eval is the contract. If the model passes, we ship. If it does not, we hold.