The hardest memory failure may be an agent that remembers enough to act but not enough to explain or undo the action.
This survey reframes always-on agents as persistent-state systems.
Their durable state includes facts and preferences， but also permissions， credentials， task ledgers， triggers， provenance， and external commitments.
The key question is whether that state remains authorized， scoped， traceable， mutable， recoverable， and safe to act on.
Across a scoped corpus of 435 works， retrieval appears in 269 and writing in 200， while only 27 expose any rollback mechanism； authority appears in 72.
The field has built the forward arc of writing， organizing， retrieving， and acting far more thoroughly than the return arc of forgetting， auditing， and recovery.
- arxiv. org/abs/2606.30306
Title： "Always-OnAgents：A Survey of Persistent Memory， State， and Governance in LLMAgents"