Ara is the assistant inside Praana. One day its answers changed character: different length, different structure, different willingness to say it was unsure. Nothing had shipped. No prompt had been edited.

What had happened

We were calling the model by a floating alias rather than a pinned version. The provider repointed that alias to a newer model, which is exactly what an alias is for. Our app followed along without being asked.

For most software that is a feature. For an assistant whose whole job is answering carefully about someone's health data, it means the behaviour you tested is not necessarily the behaviour your users get.

The fix

Praana now pins an exact model version. Upgrading is a decision someone makes, tests, and ships, rather than something that arrives overnight.

That has a cost: we do not get improvements for free, and pinned versions eventually get retired, so there is a migration to do on somebody else's schedule. We think that is the right trade for this particular thing.

The general shape of it

Anywhere your product's behaviour depends on someone else's moving target, you have handed them a release valve into your app. Sometimes that is fine. For the part that talks to people about their own health, it was not.