How to Answer
“The request is ‘delete everything you know about me’, and the honest answer is that it lands in five places, not one.
The memory rows are easy. The vector index is not — deleting a row doesn’t remove its embedding unless the index really supports deletes, and plenty only tombstone, which means the vector still shapes the graph until you rebuild. Then the conversation logs, which contain the same facts in prose. Then traces and observability, which nobody remembers and which retain whole prompts. And then the model provider’s retention window, which is a contract question rather than an engineering one.
Which means the real design decision is upstream: tag everything with a subject id at write time, so erasure is a query instead of an excavation. If you can’t enumerate where a user’s data went, you can’t honour the request — and you’ll discover that while a clock is running.
And be careful about derived artifacts. A summary generated from deleted conversations is still derived from them.”