Use when user asks anything that might need context from prior sessions, prior conversations, or stored facts. Single call returns relevant memories, recent conversation turns, and knowledge entities together. Prefer this over nexus.memory_search when query is open-ended.

Targeted semantic search over memories. Use when query has specific keyword/topic and user wants list of memories (no need for conversation/knowledge layers). For Chinese queries, mode='hybrid' falls back to trigram word_similarity.

Persist a new memory. Use when user explicitly asks to 'remember X' or when storing structured facts (preferences, decisions, code snippets with language tag). Set memory_type to 'episodic' for events, 'semantic' for facts, 'procedural' for how-tos.

Submit per-memory feedback on a previous nexus.context_retrieve call. Pass retrieve_id from earlier output. Rating 1-5, plus per-memory useful flag with optional reason. v5 feedback loop drives quality_score reranking.