Most “agent memory” is a black box living in someone else’s database. I wanted the opposite: a memory layer I actually own, that lives on my machine as a file I can read, diff, and roll back. So I built Agent Library and we open-sourced it.

Why “Library” Beats “Memory”

It turns out the framing matters - even to the model. “Store this in your library” works better than “remember this.” A library has structure: things are filed, indexed, and retrievable on purpose. “Memory” implies a fuzzy bucket the agent dips into and hopes for the best. Agent Library leans all the way into the library metaphor, and the read/write split that comes with it.

The project actually started as a small Obsidian tool for my own notes before it grew into a general-purpose library for agents.

Local-First by Design

Agent Library is opinionated, and the central opinion is local-first:

  • Your knowledge base is a file you own - you can diff it and roll it back like any other source-controlled artifact.
  • The whole stack runs locally on SQLite. No remote service required to read or write.
  • Retrieval is a real hybrid search pipeline (BM25 for lexical, reciprocal rank fusion to combine signals, and MMR to keep results diverse) rather than a single embedding lookup.

Agent Library vs Arcade

A fair question: how does this relate to Arcade? They solve different halves of the same problem.

  • Agent Library is local context: the agent’s personal, owned knowledge base.
  • Arcade is remote action and context: secure tool calling, authorization, and the thousands of integrations an agent needs to act in the outside world.

You can use them together - a local library for what the agent knows, Arcade for what the agent can securely do.

Walkthrough

Here’s a walkthrough of the design decisions behind Agent Library:

A walkthrough of Agent Library - the open-source, local-first memory layer for AI agents.

Read the full writeup on the Arcade blog, and grab the code on the Arcade GitHub.

For more about Arcade check out the website at https://www.arcade.dev/ and the GitHub https://github.com/arcadeai/