Store a fact (subject, relation, object) the agent must recall EXACTLY later, with its source. Call whenever the user states a fact, preference, decision, name, number, or rule worth remembering — it persists across sessions and is never silently distorted. Optional valid_from for valid-time.

Look up a stored fact and return the answer WITH its cited source — or an honest 'unknown'. ALWAYS call this before answering a factual or memory question instead of guessing: it returns nothing rather than hallucinating, and includes a signed, verifiable receipt. Optional as_of for valid-time.

Update a fact's value without retraining: closes live versions (valid_to=t) and opens a new one. History is preserved.

Full life-line of a fact (all versions live+closed, with sources and valid-time). Audit/compliance.

Permanently and PROVABLY delete a stored fact (GDPR / right-to-be-forgotten). Use when the user asks to forget or remove information — the fact is fully erased and you get a signed proof of deletion. object optional (omit to delete all values).

Audit knowledge for conflicts: for functional relations (one value expected, e.g. 'capital','birthdate') return any (subject,relation) holding >1 live value, showing BOTH sources — call before trusting facts that may have been updated or come from multiple sources.

Merkle root committing the entire current knowledge state (one hash).

Merkle inclusion proof that a fact is in the knowledge state (without revealing other facts).

Verify a Merkle inclusion proof (leaf, proof, root).

Verify a signed receipt returned by recall/forget (tamper-evident).

Multi-hop chain: start entity + list of relations, follows subject->object each step (exact only, 0% hallucination).

All exact fact-paths between start and end entities (each path citable).

Counts + current knowledge root.