M3 Memory

🧠 m3 Memory

Give your AI a memory that lasts.

Your AI assistant is helpful until you start a new conversation and it has forgotten what you were working on. m3 fixes that.

Your assistants remember your projects, preferences, decisions and past work, even after you close the app, start a new session or switch to a different agent. By default everything stays on your own computer, and it works offline. m3 itself needs no cloud account or API key; your AI assistant may have its own requirements.

pipx install m3-memory  # or pip install m3-memory in a virtual environment; use one, not both
m3 setup                # finds your agents and connects them to m3
m3 doctor               # checks that everything is working

No pipx yet? sudo apt install pipx (Debian, Ubuntu), brew install pipx (macOS) or py -m pip install --user pipx (Windows). If m3 is not found right after installing, open a new terminal.

Setup finds your agents and connects m3 to them. m3 setup detects your AI agents and wires m3 into each; if you run a local LLM (Ollama, LM Studio), it offers to use it to summarize and link your memories. That part is optional; to use it, install the LLM before m3 setup: Windows · macOS · Linux. That's the whole install.

New here? The 5-minute Getting Started guide walks you through your first saved memory.

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What m3 is

m3 is a memory layer for AI agents: the AI assistants that work for you, such as Claude Code, Codex, Cursor or Gemini CLI. It runs on your own computer and stores facts, decisions, preferences and conversation history so your assistants can recall them later, across sessions, across tools and across machines. Assistants reach it through MCP, the standard way AI assistants connect to tools, and you can use it from the command line too.

It is not an AI model or a chatbot. You keep using the assistants you already use; they call m3 when they need to remember or recall something.

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📅 A week with m3

Monday: you tell your AI assistant you're building a website and decide on PostgreSQL.

Wednesday: you open a new session and ask, "Where did we leave off?" Your assistant finds the decision and carries on, without you repeating it.

Friday: you switch agents, say from Claude Code to Codex. Codex sees the same project memory.

See it for yourself in a short video of one agent saving a decision that another recalls. (Developers: the same thing from the command line.)

✨ What m3 does for you

Simple to understand, easy to start, powerful when you need it. Every row links to the doc that backs it; How memory works in m3 explains the mechanics, and the technical summary and benchmarks carry the measurements.

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🎯 Better memory, fewer wasted tokens

AI assistants can only work with so much text at once, and they measure it in tokens: small pieces of words, which can also set what you pay. When your assistant searches its memory, finding the right thing first means it reads less of what it doesn't need.

An illustration, not a measurement:

  less precise search               m3: the right memory first
  1. unrelated note                 1. ✔ the decision you need
  2. unrelated note                    (it may already have what it needs)
  3. ✔ the decision you need
  4. unrelated note
  5. unrelated note

On the LongMemEval-S benchmark, the correct session was m3's first result for 91.8% of questions (459 of 500). That measures retrieval accuracy, not token savings: how much your assistant saves depends on how it uses the results. m3 returns as many as it is asked for, so precise ranking lets an assistant ask for fewer, or stop at the first good one, and keep more room for the work itself.

m3 saves context in a second, measured way: it registers only 6 of its 100+ tools when an assistant connects, so their descriptions take about 3,200 tokens instead of about 33,000 for the full catalog (Interfaces).

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How memory works in m3

When an agent (or you, from the shell) wants to remember something, it calls memory_write. m3 stores the text exactly as given, with a type, title and metadata. Later, memory_search finds it with hybrid retrieval: keyword matching (BM25), semantic similarity (local BGE-M3 embeddings) and diversity re-ranking (MMR). Nine signals contribute to the score, and every result can explain it.

When a fact changes, m3 does not overwrite it. Three mechanisms, each different:

• Similarity-based supersession (on every write). A new memory very similar to an older one of the same type (cosine similarity above 0.92 by default) but with different text becomes the current version: the older one's valid_to is closed and both stay queryable with as_of. It does not judge whether the two actually contradict, so a refinement ("PostgreSQL with connection pooling") replaces the older wording too; nothing is lost from the history. It applies only to an agent's own memories, and only when the write names its user or agent.
• Explicit supersession. An agent calls memory_supersede to replace a memory it knows is wrong.
• Contradiction detection (model-assisted). With the cognitive loop on, its Reflector stage uses a model to find memories that genuinely disagree and records them for resolution.

With the cognitive loop enabled, m3 also embeds new memories, extracts entities and relationships, and decays memories that are not used. Rolling related notes up into higher-level beliefs is a separate opt-in.

The default store is a single SQLite file. PostgreSQL is a first-class alternative when you want one store shared across machines.

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📍 Project status

The core is stable, and so are the web dashboard, the cognitive loop and the Observer & Reflector stages.

• Memory reads audited: each memory read and search hit is logged with who read it, whose data it was and when, kept 90 days, and included in GDPR export and erasure (GDPR). Chat-log reads are next.
• One config file: m3_config.toml holds every setting, and m3 config show prints each one with where it came from (Config reference). Old environment-variable names are no longer read; m3 doctor names any still set (Environment variables).
• Predictable upgrades: calendar versions (YYYY.M.D.N). A renamed setting, argument or tool keeps working, with a warning, before it is removed, and m3 doctor names anything you still use (Changelog).

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⚡ m3 at a glance: technical capabilities

m3 is a persistent, local-first memory layer for AI agents: an MCP server and a JSON-in, JSON-out command-line tool over the same store. It is not an LLM, a chatbot, a plain vector database, a RAG framework or an agent runtime.

m3 is more than a searchable memory store. It combines hybrid keyword and semantic retrieval, bitemporal history, automatic supersession, model-assisted contradiction review, a knowledge graph and background memory maintenance (the cognitive loop). Several agents can share one store; several machines can share one PostgreSQL database, or keep local stores synced through a PostgreSQL warehouse. Your existing assistants reach all of it through MCP, the CLI or framework integrations, with no new agent runtime, and it can run entirely on your own hardware.

• Tested: 5,700+ tests on Windows, macOS and Linux × Python 3.12–3.15, plus a PostgreSQL (with pgvector) lane on Linux, with the native (Rust) core that ships with m3; warnings fail the build. Security scans are published in docs/audits/. (Testing)
• Status: stable: the core, the web dashboard, the autonomous cognitive loop and the Observer & Reflector stages. Apache 2.0. (Project status · Roadmap)
• Configuration: one file, m3_config.toml. m3 config show prints every setting and where it came from. (Config reference)
• For AI agents: llm-context.md lists the real tool names and usage rules, and features.json is the machine-readable summary.

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🧭 Where to go next

New to AI memory? Start with the 5-minute Getting Started guide, then your system's install guide: Windows · macOS · Linux. Something not working? Troubleshooting · FAQ · Health FAQ.

Building with AI agents? Installation · Client setup · LangChain · CrewAI · PydanticAI · Agent instructions · For AI agents · For developers · Coding guide · CLI reference.

Evaluating memory systems? Benchmarks · Comparison with Mem0, Letta, Zep and others · Memory model · Architecture · Technical details · Sovereign deployments · Compliance.

Every document: the documentation index.

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🤝 Multi-agent memory and cross-machine use

One memory layer for many agents and machines. m3 supports concurrent agents sharing one database; separate agent, user and organization scopes; handoffs and shared tasks; and two cross-machine models: direct access to one shared PostgreSQL database, or local SQLite stores synced through a PostgreSQL warehouse.

Several agents can share one m3 memory at the same time. Each memory carries a scope: agent (one agent's own notes), user or org. Agents coordinate through handoffs into another agent's inbox and through shared task trees. Writes are safe under concurrency: on SQLite, 16 agents writing at once completed 640 writes with no failures, each waiting at most half a second. Isolation between agents is advisory by default; an opt-in filter enforces it in SQL.

Across machines there are two setups, and they work differently:

• One shared PostgreSQL store. Every machine reads and writes the same PostgreSQL 16+ database. There is no separate synchronization step; this is the setup for a fleet.
• Sync with a warehouse. Each machine keeps its own SQLite store and syncs every hour, in both directions, with a PostgreSQL warehouse: memories, embeddings, relationships, tasks and chat-log rows. The warehouse is the hub (machines never sync with each other directly), and the most recent write wins. Some local-only data, such as the entity graph, stays on its machine.

SQLite is the default and m3 setup keeps it. To move to a shared PostgreSQL store: pip install "m3-memory[postgres]", store the server's address with m3 secret set M3_PRIMARY_PG_URL, then run m3 install-m3 --db-backend postgres.

For clients that cannot run m3 locally, m3 serve exposes the memory as a remote MCP endpoint behind a bearer token. (Multi-agent · Sync · Remote clients)

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📊 Benchmarks

To compare retrieval quality, start with Session Hit-Rate (SHR). SHR measures whether the memory system retrieves the session holding the evidence a question needs, independently of the model that writes the answer.

End-to-end QA accuracy measures a different outcome: whether the whole system produces the correct answer. It depends on retrieval, the answer model, the prompt and the judge, and those are rarely held constant across published comparisons.

m3 reports both and uses SHR as its primary retrieval benchmark. SHR does not measure everything a memory layer does (supersession, history, maintenance and multi-agent coordination are not scored by it).

Retrieval Accuracy — Session Hit-Rate @ k (the primary retrieval metric)

Evaluated on the 500-question LongMemEval-S dataset, using m3's production search function:

Compared with the previous engine, v3 improves SHR@5 from 96.2% to 98.2% and SHR@10 from 96.8% to 99.2%. It reaches 100% at k=20, where the previous engine reported 97.8% at k=30 (LongMemEval issue #43). All of these are retrieval-only measurements, with no answer model.

† SHR@1 measures whether the correct session is the top-ranked result. High first-result accuracy can let an agent retrieve less context, when its retrieval strategy supports it. SHR@8 is m3's default search depth: a gold session is present for 99.2% of questions, the same as at k=10, which retrieves 25% more rows on LongMemEval-S for no gain. Other systems usually report k=5, k=10, k=20 or k=50; compare at the same k, using m3's figure for that depth.

⁂ Which aggregation. These are binary per-question recall_any@k values — the convention adjacent LongMemEval submissions report. The benchmarking report's per-question-type table aggregates slightly differently and reads marginally higher at shallow depth (98.8% at k=5, 99.4% at k=10); k=20 is 100.0% either way. The table above quotes the more conservative figures.

End-to-End QA Accuracy (depends on the answer model and the judge)

92.0% accuracy (460/500 correct responses) without using the dataset's question-type labels (no oracle routing). This measures the whole system; see the note above on why it is not comparable across systems the way SHR is:

How the QA figure was produced. m3 retrieves; it does not answer questions. In deployment the calling agent chooses what to retrieve and writes the answer. The benchmark harness plays that role: it chooses retrieval options per question (session expansion and a precomputed recall surface, both available in m3's engine but off by default) using a question-text router that is part of the harness, and it supplies the answer prompts and model. m3's built-in intent routing is on by default in both. The retrieval figures (SHR) use m3's search alone.

Methodology and reproducibility details are located in the LongMemEval-S Benchmarking Report.

Performance

• Writes: about 2 ms with the embedding deferred: text search finds the memory at once, and with the cognitive loop enabled, semantic search finds it in under 30 seconds. With the embedding inline, a write takes about 31 ms.
• Search: about 45 ms (p50) on the benchmark store. At 50,000 memories, 0.45 s on SQLite and 0.27 s on PostgreSQL with pgvector. A real 83,000-memory store answers in 2.7 s on SQLite, or 0.54 s on PostgreSQL with pgvector.
• Concurrency: 16 agents writing to SQLite at once lost nothing and waited at most half a second.
• Native core: the Rust core speeds up MMR re-ranking 95× to 846× and batch cosine 97× to 178×; without it, results are the same, more slowly.

(Performance · Oxidation benchmarks)

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🔌 Interfaces and integrations

Two interfaces, one store. The MCP server and the m3 CLI reach the same database. Every tool reads JSON on stdin and writes JSON on stdout, grouped as memory, files, chatlog, tasks, agent, admin, conversations, diagnostics and entity. A dropped MCP connection is not a memory outage: the CLI keeps working until the client reconnects.

The full catalog without the context cost. 100+ tools sit in 9 domains, but only 6 register at startup: memory_write, memory_search, memory_supersede, memory_get, chatlog_search and m3_call. Across real development sessions the four memory tools (memory_write, memory_search, memory_supersede, memory_get) took 95% of all direct tool calls. An agent reaches any other tool by name through m3_call, or loads a whole domain.

Agents and frameworks:

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🛡️ Privacy, security and operations

After installation, m3 runs offline by default. It contacts the internet only for what you turn on: a cloud LLM you configure for enrichment, sync with a warehouse you name, and the daily version check if you said yes to it in m3 setup (a single request to pypi.org).

Sovereign Local Embedder

BGE-M3 (1,024 dimensions) runs on your machine after installation: one shared embed server on 127.0.0.1:8082 that every m3 process reuses, so one model sits in memory. In-process embedding is an opt-in at m3 setup: about 1.9× faster on short text and 1.75× on medium text, at the cost of one model copy per process. m3 embedder install-gpu adds a CUDA build (tested) or Vulkan and Metal builds; any OpenAI-compatible embeddings endpoint also works (m3 config set embed.url …). (Embedding: shared vs in-process)

Rust-Oxidized Performance Core

A native Rust core (m3_core_rs) is installed by default and speeds up ranking and vector math (measured in Performance); without it, m3 returns the same results in pure Python, more slowly. (Oxidation Benchmarks)

Enterprise Security & Compliance

• FIPS 140-3 Ready: m3 implements no cryptography; its own (secrets vault, key derivation, HMACs, audit chain, random keys) runs through one provider that a validated module (wolfCrypt FIPS) can serve, and every network path is named and fails closed under FIPS mode. Ready, not validated: see the FIPS Boundary Reference for each path and the deployment profiles.
• Air-Gapped Install: Supports installation without internet access via pre-compiled python wheels. (See Sovereign Deployment Guide & FIPS Boundary Reference).
• Storage Location: databases (~/.m3/engine), configuration (~/.m3/config) and logs (~/.m3/logs) live under separate roots, each relocatable under [paths] in m3_config.toml, so they can be secured independently. (Config reference · Architecture)

Operations

• Web dashboard: m3 dashboard serves a local control panel on 127.0.0.1:8088: the knowledge graph, a memory browser, the conflict and audit log (with GDPR actions) and system health. (Dashboard)
• Wiki: m3 wiki generate compiles your memories into an interlinked Markdown vault, a self-contained HTML viewer, or an Obsidian vault. (Wiki)
• Diagnostics: m3 doctor checks the whole install and m3 doctor --fix repairs it; m3 config show --origin prints every setting and its source.
• Audit and GDPR: every memory read and search hit is logged with the reader, the data subject and the time, kept 90 days; gdpr_export and gdpr_forget cover Articles 20 and 17. (GDPR)

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🎯 Who This Is For

m3 is a great fit if...

• You run a homelab or self-hosted stack: m3 is a single pip install with no account, no API key, and no outbound calls unless you turn them on — it runs on the hardware you already own, alongside your other self-hosted services. SQLite by default (zero infrastructure); PostgreSQL when you want a shared store across machines.
• You operate under sovereignty or data-residency requirements — corporate, government, defence, healthcare, or any regulated environment: memory and embeddings never leave your boundary. The embedder runs on your own hardware, the store is a file you control, and installation works fully air-gapped from pre-compiled wheels. FIPS 140-3-ready crypto (crypto.fips_mode), GDPR gdpr_forget / gdpr_export, audit logs, and relocatable storage roots so databases and configuration can be secured independently.
• You want the freedom to switch or add agents without losing what they know: change tools on the fly or down the road — Claude Code, Gemini, OpenClaw, Hermes, whatever comes next — and your project's knowledge carries over instead of disappearing with the switch.
• You build with LangChain/LangGraph: An advanced replacement for standard memory models, adding bitemporal queries, supersession with version history, and local embeddings.
• You build with CrewAI (v1.10–1.x): A drop-in StorageBackend (Memory(storage=M3StorageBackend(user_id="crew-alpha"))) that gives CrewAI bitemporal recall, supersession with version history, and local embeddings — plus the thing single-vector stores can't do: a CrewAI-written memory can also be searchable by every other m3 agent (Claude Code, Gemini, LangChain) if you want. pip install m3-memory[crewai]. See the CrewAI integration guide.
• You build with PydanticAI: m3-backed memory as either drop-in tools + auto-recall (register_m3_tools, m3_recall_processor) or a formal M3MemoryToolset (a real PydanticAI AbstractToolset). Built on Pydantic v2, so it runs on Python 3.14 with a plain pip install m3-memory[pydantic-ai]. See the PydanticAI integration guide.
• You need security and compliance: Built-in gdpr_forget and gdpr_export tools, air-gapped support, and audit logs.
• You value privacy: no cloud service or subscription required; nothing leaves your machine unless you configure it to.

m3 is NOT a fit if...

• You need a hosted SaaS dashboard with managed infrastructure (use Letta).
• You don't want persistent memory: you want each session to start fresh, with no ability to retrieve prior sessions' knowledge — m3 exists to do the opposite, so your agent's built-in defaults are the simpler fit.

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⚖️ How m3 Compares

m3 is the local-first, MCP-native memory layer that stays on your machine and works with the agents you already use. Mem0 is a cloud-oriented memory service with opinionated extraction. Letta is a full agent runtime that owns the conversation loop. Zep and Graphiti are graph-first systems that typically need a dedicated graph database. m3 adds persistent, searchable, versioned memory without asking you to change your agent stack or run extra infrastructure.

A full, feature-by-feature comparison table — m3 vs Mem0, Letta, Zep, Graphiti, LangChain Memory / LangMem, agentmemory, Chronos, Hindsight, Mastra OM, Memento, and more — with sourced benchmarks and honest "when to choose the other tool" guidance, lives in COMPARISON.md.

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🛠️ For developers: a memory backend, not a framework

MCP is optional. m3 is a memory layer: it owns durable, searchable, multi-agent memory and stops there, so it drops into whatever you already have. Every tool reads JSON on stdin and writes JSON on stdout, so m3 is scriptable from any language, hook, CI step or cron job, with no SDK and no MCP server:

echo '{"query":"auth","k":3}' | m3 memory memory_search --json-file - | jq '.items[].id'

Results compose, and language-specific work (code parsing, VCS watching) stays on your side of the boundary. Using m3 for coding work has the patterns: bulk updates from a search, indexing code symbols with ast or tree-sitter, git hooks and CI steps. (jq is not a dependency; any JSON parser works.)

👀 See it work

What your agent does through MCP, from the shell (output captured from a real run; ids and scores differ on your store). Save a decision:

$ m3 memory memory_write --type decision --title "project-database" \
    --content "We chose PostgreSQL for our website."
"Created: 6795c684-53cb-4a6a-9518-819dbc585fe5"

Later, in another session or another agent connected to the same m3, ask in your own words:

$ m3 memory memory_search --query "Which database did we decide to use?" --k 1
{
  "count": 1,
  "items": [
    {
      "id": "6795c684-53cb-4a6a-9518-819dbc585fe5",
      "content": "We chose PostgreSQL for our website.",
      "title": "project-database",
      "type": "decision",
      "importance": 0.5,
      "bm25_score": 0.0,
      "score": 0.9122939705848694
    }
  ],
  "query": "Which database did we decide to use?",
  "grade_with": [
    "6795c684-53cb-4a6a-9518-819dbc585fe5"
  ]
}

The question shares no words with the memory (bm25_score 0.0), and m3 still finds it, by meaning. Your agent calls the same tools, so it recalls the decision instead of asking you again. Core Tools lists the five you'll use most. Prefer to watch? A short captioned video shows one decision saved in one agent and recalled by another (download).

⌨️ The m3 CLI

Content comes from --content or from a file (memory_write_from_file --path), and logs go to stderr, so stdout pipes cleanly. Check that m3 is up with m3 --version; if the CLI answers, your memory is reachable even when an MCP client has dropped its connection (/mcp reconnects Claude Code). (CLI reference)

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📦 Installation

Python 3.12 or newer is required. On Python 3.11, pip silently keeps you on 2026.9.12.0, the last release that supported it. Check with python --version; HOW-TO-UPGRADE.md has the upgrade per OS. Your memories are unaffected: they live outside the virtualenv, under ~/.m3/engine.

The install at the top covers the common path (pip install m3-memory → m3 setup). This section adds the alternatives: the shell installer, per-agent wiring, and manual MCP configuration.

The One-Liner (macOS & Linux)

curl -fsSL https://raw.githubusercontent.com/skynetcmd/m3-memory/main/install.sh | bash

• For Windows, please follow the Windows Manual Installation Guide.
• To install manually on any platform, refer to the OS-Specific Install Instructions or examine the installer script.

Developer Setup Wizard

If you are developing inside python environments:

pip install m3-memory
m3 setup

The m3 setup wizard automatically detects your installed agents — Claude Code, Codex, Cursor, Cline, Gemini CLI, OpenCode, Antigravity, OpenClaw, Hermes — and wires the m3 memory MCP server into each, installs settings files/hooks, provisions the sovereign CPU embedder, and performs a system diagnostic. Detection and wiring re-run on every m3 update/m3 setup, and m3 doctor --fix repoints any config whose paths have moved — so an agent you install later gets picked up automatically the next time you run setup or update.

Every agent and framework above connects through m3 setup or its plugin; see the integrations table.

Manual MCP Server Configuration

To expose m3 to any Model Context Protocol host, add it to your configuration file:

{
  "mcpServers": {
    "memory": {
      "command": "m3"
    }
  }
}

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🧰 Core Tools

m3 has 100+ tools; these five are your primary interface. Agents should use these names exactly: an invented name returns unknown_tool.

Rules that keep memory accurate:

• Search before you write. Call memory_search first; if a similar memory exists, supersede it, or edit it with memory_update (through m3_call), instead of adding a duplicate.
• Supersede, don't overwrite. Corrections go through memory_supersede (or the automatic check on write), so the old version stays queryable with as_of.
• Pin protects against ageing, not correction. memory_pin exempts a memory from decay and expiry; a pinned memory can still be superseded when it becomes wrong.

Complete parameters: the Agent Instructions Guide and the full MCP tool catalog; machine-readable schemas are in docs/tools/MCP_CATALOG.json.

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🤖 For AI Agents

Drop the ruleset examples/AGENT_RULES.md into your workspace to teach your agent the habits that keep memory clean (search before writing; update instead of duplicating). llm-context.md lists the real tool names and usage rules, features.json is the machine-readable summary, and copy-paste prompts that let an agent install m3 itself are in the agent instructions.

Operational facts for agents that read only this page:

• The startup tools are memory_write, memory_search, memory_supersede, memory_get, chatlog_search and m3_call; every other tool is reachable through m3_call.
• Search before writing, and use memory_supersede for corrections.
• Memories have a scope (agent, user or org) and can be pinned; pinning stops decay, not supersession.
• The embedder runs locally on 127.0.0.1:8082 by default. If semantic search returns nothing, check embedder_status, or download the model with m3 embedder fetch-model.

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🎬 See it in action

Supersession on write and version history

Hybrid Search Scoring Details

Multi-Device Database Sync

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💬 Community

How to Contribute · FAQ for Developers · Good First Issues

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📜 License & Attributions

This project is licensed under the Apache License 2.0. See LICENSE for details.

Built with

m3 Memory is authored and maintained by skynetCMD. It was built with the help of AI coding assistants — Gemini CLI, Claude Code, and Google Antigravity — which contributed code under the author's direction. (They are tools that assisted; they are not maintainers, sponsors, or co-owners of the project.)

Asset & Icon Credits

The provider badges under docs/badges/ embed small logo glyphs:

• OpenClaw & OpenCode icons are from the MIT-licensed LobeHub icon set (lobe-icons).
• The Hermes badge uses a generic caduceus glyph.

See NOTICE for the full third-party attribution list.

PyPI downloads, all-time and last 30 days. GitHub clones are unique clones. Badges are regenerated on a schedule by star-history.yml.

Python: m3 core runs on Python 3.12, 3.13, 3.14 and 3.15. The optional framework extras follow their own caps — PydanticAI is 3.14-native (plain pip install); CrewAI requires 3.12–3.13 with m3 (a 3.14 escape hatch is documented).

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