An AI query response processed by an artificial intelligence (AI) module using a neural model is received as an input. The query response is compared to one or more tokenized facts of the compressed blocks at a data level. Comparing includes computing a similarity score of a vector derived from the tokenized query response to one or more vectors derived from the one or more tokenized facts. Responsive to a verification result failing to meet a similarity score threshold, it can be determined that a hallucination exists in the AI query response and a policy-based action, such as blocking the AI query response, can be taken. Responsive to the verification result meeting the similarity threshold, the AI query response can be allowed to proceed.