Memory Deep Dive: Building the Three-Tier Stack
OpenClaw Academy · Part 2, Issue 12
The concept (Issue 11) established what the three memory horizons are. This issue implements all three. The vault asset is the complete setup — five files you can deploy in under an hour, covering session recall, daily summary automation, semantic curation, and the Active Memory plugin.
One important framing before implementation: memory architecture is a state management problem, not just a retention problem. The question is not “how do I make the agent remember more?” It is “what information should persist between sessions, for how long, and in what form?” Engineers who approach memory as a state management problem build systems that stay coherent over months. Engineers who treat it as “add things to MEMORY.md” build systems that grow bloated and eventually degrade.
The vector store memory plugin vs the default
The default OpenClaw memory backend is SQLite — a local database storing session records and the MEMORY.md content. SQLite works well for personal use with a single user and moderate memory volumes. It has two ceilings:
First: full-text search only. SQLite matches exact keywords. If your memory contains “prefers concise bullet summaries” and you type “how should I format this?”, SQLite doesn’t connect them. A vector store does — it finds semantically similar content regardless of exact keyword match.
Second: single-user only. SQLite on a local file is per-machine. For multi-user deployments (a team sharing an agent) or deployments spread across machines, SQLite doesn’t share state.
The vector store memory plugin replaces SQLite with a local ChromaDB or Qdrant instance. The Active Memory plugin (simpler, no external database) adds embedding-based retrieval on top of the default storage without replacing it. For most personal deployments, Active Memory is the right choice. For team deployments or very large knowledge bases, the full vector store plugin is worth the added complexity.
Github Link:
https://github.com/sysdr/openclaw-academy/tree/main/part-2/issue-12/vault-files
