Originally published on the Invoance blog.
Your AI's output is gone the moment it returns
Most teams treat AI outputs like ephemeral function returns. The model responds, the response goes to the user, maybe a row gets written to a database, and that is the entire trail. When a customer disputes an answer six months later, when a regulator asks what your model produced for user 4f9a on March 14 at 2:47 PM, or when your legal team needs to defend a decision in a deposition, that database row is your evidence.
The problem is that database rows can be edited, deleted, or corrupted, accidentally or otherwise. There is nothing in the row that proves it has not been touched since the AI generated it. There is nothing that proves your timestamp column was not bulk-updated by a migration last quarter. There is nothing that proves the input column matches the prompt the model actually saw.
Your logs are a story you are asking someone to take on faith. That works until somebody has a reason to challenge them. The first thing opposing counsel, an auditor, or a regulator will do is question the chain of custody. Without a cryptographic anchor, you have no answer to that question.
