Local-first agent memory with zero LLM in the retrieval path. No cloud. No token cost. No rephrasing. Your words, returned verbatim — every qualifier, every detail, intact.
Every other memory tool calls an LLM when you retrieve. Memex doesn't. BM25 + dense vectors + reciprocal rank fusion. Pure math, zero inference tokens, zero latency tax.
You stored "auth tokens expire after 3600 seconds. The window is non-configurable." Other tools return "authentication has a configurable timeout." Memex returns your exact words — the qualifier survives, every detail intact.
Memex binds to 127.0.0.1. No cloud account. No third-party processor. No API keys to manage. Your memories live in ~/.memex/ — on your machine, under your control.
mem0 costs $2 per 1,000 queries. Zep costs $3. Letta costs $4. Memex costs nothing on the default path — no LLM call means no inference cost. Scale to millions of queries without a billing surprise.
Memex works with every agent: Claude Code, Cursor, Codex, Windsurf, Continue.dev, Zed. SDKs in TypeScript, Python, Go, and Rust. CLI with doctor, backup, graph, TUI, benchmark, audit, and more.
No cloud. No LLM tax. No vendor lock-in.
| mem0 | Zep | Letta | Memex | |
|---|---|---|---|---|
| Local-first | — | — | — | ✓ |
| Zero LLM in retrieval | — | — | — | ✓ |
| Verbatim passages | — | — | — | ✓ |
| Cost / 1K queries | $2 | $3 | $4 | $0 |
| R@1 (independent) | 49% | 63.8% | — | 83.2% |
| Graph memory | — | Neo4j | — | SQLite |
| SDKs | Python | Python | Python | 4 languages |
| External deps | Cloud | Neo4j + LLM | LLM | None |
| Compliance docs | — | — | — | SOC2, HIPAA, GDPR |
"A summary can preserve 'we tried the migration' while dropping why it failed. Memex keeps those details in the stored note — not a generated fact."
Design Principle — Verbatim Fidelity
Python 3.10+, macOS or Ubuntu, Ollama running locally. That's it.
Stop re-explaining context. Stop losing decisions between sessions. Give your agent memory that stays.