Zettelkasten Second Memory: memory tool for Hermes Agent

Plugin that turns AI conversations into a linked Zettelkasten knowledge base with MCP tools

What Zettelkasten Second Memory does

Zettelkasten Second Memory is a TypeScript plugin that turns AI conversations into a permanent Zettelkasten knowledge base. Notes are atomic, stored as Markdown with SQLite, and connected by 11 semantic link types such as supports, refines, extends, contradicts and example-of. Search uses SQLite FTS5 with a LIKE fallback and handles Chinese tokenization.

A CEQRC pipeline distills fragmentary notes into permanent knowledge, zk_find_zombies flags notes older than 180 days with no backlinks, and a glow ranking scores importance from PageRank, citations and recency decay. Cold notes move to an archive folder, with an audit log and a nightly auto-archive at 2:00 AM. It was developed mainly for OpenClaw 2026.4 and 2026.6, and Hermes Agent v0.17.0 or newer can reach all tools through an optional Streamable HTTP MCP bridge, which the README labels experimental.

Key features

Atomic, structure and source note types stored as Markdown
11 semantic link types for a bi-directional knowledge graph
SQLite FTS5 plus LIKE search with Chinese tokenization
CEQRC knowledge distillation pipeline
Zombie note detection, glow ranking and nightly archiving with an audit log
Optional Streamable HTTP MCP bridge for Hermes Agent

When to use it

Capturing knowledge from agent conversations as permanent linked notes
Finding the shortest weighted path between two ideas in a note graph
Letting Hermes Agent search and write notes through MCP tools

Who it is for: Users who keep a second-brain note system and want an agent, mainly OpenClaw and optionally Hermes Agent, to write and retrieve notes.

How it fits with Hermes Agent

Hermes Agent v0.17.0 or newer is supported as an optional, experimental integration through an MCP HTTP bridge; the main target is OpenClaw.

How to install Zettelkasten Second Memory

These commands are copied from the project's README. Check the repository for the latest steps before you run them.

git clone https://github.com/cx2002302-lang/zettelkasten-second-memory.git
cd zettelkasten-second-memory
npm install
npm test

Requirements: Node.js 22.14.0 or newer (built-in node:sqlite), OpenClaw 2026.4.24 or 2026.6.x, and optionally Hermes Agent v0.17.0+

Note: The plugin is at version 1.0.0-beta.8 and Hermes Agent support is labeled experimental.

FAQ

What is Zettelkasten Second Memory?

It is a plugin that captures knowledge from AI conversations as atomic Markdown notes linked into a Zettelkasten graph, with search, distillation and archiving, and exposes its tools over MCP.

Does Zettelkasten Second Memory work with Hermes Agent?

Yes, experimentally. The README lists Hermes Agent v0.17.0 or newer through an optional Streamable HTTP MCP bridge, while OpenClaw is the main tested target.

What do I need to run Zettelkasten Second Memory?

You need Node.js 22.14.0 or newer for the built-in node:sqlite module and a compatible OpenClaw version. Hermes Agent v0.17.0 or newer is optional.