Fact-check a claim against a piece of evidence using natural-language inference. Returns a grounded verdict — Supported, Refuted, or Not Enough Evidence — with a confidence (0..1) and an abstained flag. Use it to check whether a statement is actually backed by a source before trusting or repeating it. If abstained is true, treat the result as 'cannot verify — do not rely'.

Hallucination guard for RAG / agent answers. Pass the model's generated answer and the retrieved context; returns whether the answer is grounded in the context. Treat any verdict other than 'Supported', or abstained=true, as 'ungrounded / likely hallucination' and have the agent retract or re-retrieve.

Same as verify_claim but with a raised abstention threshold — abstains more readily. Use when a wrong 'Supported' is costly (compliance, legal, medical-adjacent) and the agent must not over-assert.