The best-benchmarked open-source memory system for AI coding assistants.

Every claim ships with the harness that proves it. Run the benchmarks yourself.

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iai-mcp

Independent Autistic Intelligence — a local memory layer for Claude (and other MCP-compatible assistants).

Table of contents

• What it is
• Quick start
• Usage
• How it works
• Benchmarks
• Configuration
• Doctor
• Notes for AI assistants
• Status and limitations
• Compatibility
• About the name
• Authors
• License
• Contributing

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What it is

A local server that speaks the MCP protocol and gives Claude, and any other MCP-compatible assistant, a long-term memory. It captures every turn of every session verbatim, organizes those captures over time into a personal map of who you are, and serves a small slice of relevant memory back at the start of each new conversation. You never have to say "remember this" or "what did we say last time?".

I built this for myself. It worked. I've been running it daily for months, and now I'm sharing it. The benchmarks were mostly for my own curiosity. I wanted to know if it actually works or if I'd just gotten used to it.

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Quick start

Prerequisites

• macOS (Apple Silicon tested)
• Python 3.11 or 3.12
• Node.js 18+
• Claude Code or Codex CLI as the MCP host
• ~500 MB free disk

Windows and Linux not supported yet but I'm working on it.

Install

git clone https://github.com/CodeAbra/iai-mcp.git
cd iai-mcp
bash scripts/install.sh

The installer creates a Python venv, installs dependencies (LanceDB, sentence-transformers, torch-hd, NetworkX, igraph), builds the TypeScript MCP wrapper, pre-downloads the default embedding model (~130 MB), symlinks the CLI to ~/.local/bin/iai-mcp, and on macOS registers the daemon with launchd.

Make sure ~/.local/bin is on your PATH:

export PATH="$HOME/.local/bin:$PATH"  # add to ~/.zshrc or ~/.bashrc
iai-mcp --version

Install the capture + recall hooks

This is what makes memory ambient. Without these hooks iai-mcp reads memory but never writes conversation content and never injects recall at session start. One command wires all three:

iai-mcp capture-hooks install       # copies all three hooks + patches ~/.claude/settings.json
iai-mcp capture-hooks status        # verify: should print "status: ACTIVE"
iai-mcp capture-hooks uninstall     # clean removal if ever needed

For Codex:

iai-mcp capture-hooks install --target codex

To install both:

iai-mcp capture-hooks install --target all

What the install does:

• Copies three hook scripts from deploy/hooks/ to ~/.claude/hooks/ (chmod +x):
  • iai-mcp-turn-capture.sh (UserPromptSubmit, timeout 5s) — appends each prompt + the preceding assistant turn(s) to a per-session buffer as pure file IO. Zero daemon RPC during the session.
  • iai-mcp-session-capture.sh (Stop, timeout 35s) — at session end, rolls the buffer over for the daemon to drain, and runs iai-mcp capture-transcript --no-spawn as a safety net.
  • iai-mcp-session-recall.sh (SessionStart, timeout 30s) — calls iai-mcp session-start and pipes the assembled memory prefix to stdout, which Claude Code injects as additionalContext before the first prompt. Fail-safe: empty store or unreachable daemon yields empty stdout — session start is never blocked.
• Registers iai-mcp in Claude Desktop's config if installed.
• Idempotent — re-running detects existing entries and makes no changes.
• No secrets, no tokens, no network calls.

What happens at runtime:

• Every prompt (per-turn hook): appends new transcript turns to the session buffer. ~5 ms per turn, no embedding, no daemon socket.
• Every session end (Stop hook): rolls the buffer over, captures any remaining turns. Fail-safe exit 0.
• Every session start (recall hook): assembles the cached memory prefix and pipes it to Claude. Empty store or unreachable daemon → empty stdout.
• When idle (daemon): drains the buffer through the shield → embed → dedup → encrypted insert pipeline on the WAKE → DROWSY edge (5-min idle) and after every REM cycle.

Connect your MCP host

Claude Code:

claude mcp add iai-mcp -- node "$(pwd)/mcp-wrapper/dist/index.js"

Or edit ~/.claude.json directly:

{
  "mcpServers": {
    "iai-mcp": {
      "command": "node",
      "args": ["/absolute/path/to/iai-mcp/mcp-wrapper/dist/index.js"]
    }
  }
}

Use the absolute path. ~ and $HOME won't expand here.

For Claude Desktop (untested), edit ~/Library/Application Support/Claude/claude_desktop_config.json.

Codex CLI:

[mcp_servers.iai-mcp]
command = "node"
args = ["/absolute/path/to/iai-mcp/mcp-wrapper/dist/index.js"]

[mcp_servers.iai-mcp.env]
IAI_MCP_PYTHON = "/absolute/path/to/iai-mcp/.venv/bin/python"
IAI_MCP_STORE = "/Users/you/.iai-mcp"
TRANSFORMERS_VERBOSITY = "error"
TOKENIZERS_PARALLELISM = "false"

Codex hooks are stable in current Codex CLI builds. If hooks are disabled by local policy or an older install, enable [features].hooks = true in ~/.codex/config.toml.

Verify

iai-mcp doctor
iai-mcp daemon status

Restart Claude Code. Start a session, do some work, exit. Then:

tail ~/.iai-mcp/logs/capture-$(date -u +%Y-%m-%d).log

You should see a rc=0 line. That's your first memory.

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Usage

You do not call iai-mcp directly during a session. Once it's connected:

Capture is automatic. Every turn, yours and the assistant's, is recorded verbatim with timestamps and session metadata. You don't say "remember this."

Recall is automatic. When a new session starts, the daemon assembles a small relevant slice of your history and injects it into the conversation prefix. You don't say "what did we say."

Consolidation runs idle. Between sessions, the daemon merges duplicates, strengthens recall pathways for things retrieved often, and prunes weak edges. The system gets quietly better at remembering you over time.

After a few weeks of regular use the difference becomes noticeable. The assistant stops asking the same orientation questions, references things you mentioned in passing, and adapts to your style without being told.

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How it works

The daemon is a Python process that runs in the background. Your MCP client connects to it via a Unix socket. No network exposure.

Memory is stored in three tiers:

Episodic is verbatim, timestamped fragments of what was said. Write-once, never overwritten or rewritten.

Semantic is summaries induced from clusters of related episodes during idle-time consolidation.

Procedural is a small set of stable parameters about you, learned over time: preferences, style cues, recurring patterns. Eleven sealed knobs that shift based on what works.

A background pass runs periodically (sleep cycles): it clusters episodes, builds semantic summaries, decays old unreinforced connections, and reinforces frequently co-retrieved paths. Things you haven't revisited fade naturally. There's an optional "insight of the day" step that makes one Anthropic API call, but it's off by default.

Recall combines three signals: semantic similarity, graph-link strength, and recency. All ranked together.

All records are encrypted at rest with AES-256-GCM. The key lives in ~/.iai-mcp/.key (mode 0600). Back it up. Lose the key, lose the memories.

Everything lives at ~/.iai-mcp/. Embeddings are computed locally with bge-small-en-v1.5. The only data that leaves the machine is your normal conversation with whatever LLM API your client uses.

Claude Code  <--MCP-stdio-->  TypeScript wrapper  <--UNIX socket-->  Python daemon  <-->  LanceDB

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Benchmarks

I made these because I wanted honest numbers. Every harness ships in bench/. Run them on your machine, get your own results.

Metric	Target	Measured
Verbatim recall (byte-exact)	>=99%	>=99% at N=10k
Recall p95 latency	<100 ms	<100 ms at N=10k
RAM at steady state	<=300 MB	~150-300 MB
Session-start tokens (warm cache)	<=3,000	<=3,000
Session-start tokens (cold)	<=8,000	<=8,000

python -m bench.verbatim                     # verbatim fidelity
python -m bench.neural_map                   # recall latency
python -m bench.memory_footprint             # RAM usage
python -m bench.tokens                       # session-start cost
python -m bench.total_session_cost           # full 10-turn cost
python -m bench.trajectory                   # 30-session corpus
python -m bench.contradiction_longitudinal   # falsifiability
python -m bench.longmemeval_blind            # LongMemEval-S blind run

The LongMemEval-S run is blind on purpose. No dataset-specific tuning, no hyperparameter sweep. The numbers are what they are.

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Configuration

Variable	Default	What it does
IAI_MCP_STORE	~/.iai-mcp/	Data directory
IAI_MCP_EMBED_MODEL	bge-small-en-v1.5	Embedding model. bge-m3 for multilingual at ~3x size.

Switching embedders requires re-embedding the store: iai-mcp migrate reembed.

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Doctor

iai-mcp doctor runs 14 checks against the daemon, the store, and the runtime state. Output is one line per check: PASS, WARN, or FAIL.

iai-mcp doctor

What it checks:

#	Check	What it means
a	Daemon alive	Is the daemon process running?
b	Socket fresh	Can the UNIX socket accept a connection?
c	Lock healthy	Is the process lock held correctly?
d	No orphan core	No leftover stdio core process without a daemon
e	State file valid	.daemon-state.json parses and has expected fields
f	LanceDB readable	Can the records table be opened and queried?
g	No duplicate binders	Only one process is bound to the socket
h	Crypto file state	Encryption key exists, correct permissions (0600)
i	Lance versions count	LanceDB version manifests aren't piling up
j	Lifecycle current state	Current FSM state is valid
k	Lifecycle history 24h	Recent lifecycle transitions look sane
l	Sleep cycle status	Last sleep cycle completed or is running normally
m	Heartbeat scanner	Wrapper heartbeat files are fresh
n	HID idle source	Idle detection source is available

14/14 PASS is healthy. 13/14 with check (b) failing during a sleep cycle is also normal (the socket is busy during consolidation). Multiple FAILs or a FAIL on (a) or (f) means something is actually wrong.

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Troubleshooting

Symptom	Cause	Fix
import lancedb crashes with Illegal instruction (SIGILL)	CPU lacks AVX2 (Intel Celeron N4020, Atom, older Core2, some embedded ARM). LanceDB has no SSE-only fallback.	Deploy on a host with AVX2 and connect over SSH stdio — see Headless / VPS deployment.
keyring.errors.NoKeyringError on first run	Storage is file-backed at ~/.iai-mcp/.crypto.key. Older setups referenced a Keychain-only path.	iai-mcp crypto init (idempotent). iai-mcp daemon install calls this automatically on fresh installs.
Daemon crashes on first start with CryptoKeyError	Fresh install bypassed daemon install (e.g. systemd unit copied manually) — no .crypto.key exists yet.	iai-mcp crypto init, then restart the daemon.
iai-mcp daemon install says "launchd bootstrap failed"	Existing plist from previous install	iai-mcp daemon uninstall first, then install again.
Daemon "active" but no tick events	First-week bootstrap (no quiet-window data yet)	Wait 2 h of MCP idle, or force: iai-mcp daemon force-rem
Claude Code doesn't show iai-mcp tools after claude mcp add	Forgot to fully quit — "reload window" is not enough	killall Claude then relaunch. Check ~/Library/Logs/Claude/*.log for MCP stderr.

Headless / VPS deployment

If your local CPU lacks AVX2 (Intel Celeron N4020 Gemini Lake, older Atoms, some embedded ARM) import lancedb will crash with SIGILL and the daemon can't run locally. The escape hatch is to run the daemon on a remote host (any cheap VPS with AVX2) and let Claude Code spawn the MCP wrapper over SSH stdio.

On the remote host (Linux example):

git clone https://github.com/CodeAbra/iai-mcp.git /opt/iai-mcp
cd /opt/iai-mcp && bash scripts/install.sh
loginctl enable-linger "$USER"
iai-mcp daemon install --yes
systemctl --user status iai-mcp-daemon.service

On the local host:

claude mcp add iai-mcp -- \
  ssh -o ConnectTimeout=5 -o ServerAliveInterval=30 \
      user@vps.example.com \
      node /opt/iai-mcp/mcp-wrapper/dist/index.js

Round-trip latency on the same continent is typically 10-50 ms per call.

Doctor caveats on headless hosts. iai-mcp doctor check (n) "HID idle source" returns WARN because there is no display hardware. The daemon's wake/sleep cycle falls back to heartbeat-idle, which works correctly. Check (b) "socket" may FAIL transiently during DREAMING state. Both are expected.

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Notes for AI assistants helping with installation

If you're an AI model helping a user install or debug iai-mcp, read this before diagnosing anything.

The daemon has four FSM states: WAKE, TRANSITIONING, SLEEP, DREAMING. Separately, the wrapper-layer lifecycle has four states: WAKE, DROWSY, SLEEP, HIBERNATION. These are two different state machines in two different files. Don't confuse them.

Things that look broken but are not:

• last_tick_at hasn't changed in hours. This is a sleep-cycle tick timestamp, not a process heartbeat. The daemon can be alive and healthy with a stale last_tick_at. Check iai-mcp daemon status instead.
• fsm_state: DREAMING for hours. Normal. The daemon is running a sleep cycle. Wake transitions are event-driven (a new session arriving wakes it), not time-driven.
• status: deferred in the capture log. This is the only path the Stop hook takes. It writes captures to ~/.iai-mcp/.deferred-captures/ and the daemon picks them up on its next tick. This is by design, not a failure.
• iai-mcp doctor shows 13/14 PASS with check (b) "socket unreachable." Expected when the daemon FSM is in SLEEP or DREAMING. The socket is intentionally unresponsive during consolidation passes. This is healthy.
• Cold start takes a few seconds. The daemon needs to initialize the LanceDB store and load the embedding model into memory. Don't kill it because it hasn't responded in 5 seconds.

Actual problems look like: iai-mcp daemon status returning ok: False, doctor showing multiple FAIL results, or the daemon process not existing at all (pgrep -f iai_mcp.daemon returns nothing).

When in doubt, run iai-mcp doctor and read what it says. The output is self-explanatory.

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Status and limitations

This is experimental. I built it for myself, it works on my machine, and I'm sharing it because it might be useful to you. No SLA, no support guarantee. Breaking changes are possible between versions. Pin a commit hash if you depend on stability.

Limitations worth knowing about:

• The default embedding model is English-only. The assistant translates to English on the way into memory. The opt-in bge-m3 model removes this constraint at a cost of ~3x storage and slower indexing.
• No cross-machine sync. The data lives where the daemon runs. Backup is cp -a ~/.iai-mcp/ somewhere safe.
• No GUI. Inspection happens through CLI subcommands (iai-mcp doctor, iai-mcp daemon status, iai-mcp topology).
• Cold start on a freshly booted machine takes a few seconds while the daemon initializes caches.
• Recall quality on the first ~10 sessions is mediocre. The system needs material to consolidate before it gets useful.

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Compatibility

Claude Code is the primary host, validated in daily use.

Claude Desktop should work (uses claude_desktop_config.json instead of ~/.claude.json) but hasn't been tested end to end.

Codex CLI supports the MCP wrapper and ambient capture through a Stop hook.

Other MCP-over-stdio hosts speak the same protocol and should work in principle. Not tested.

If you get it running on something else, open an issue or PR.

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About the name

IAI stands for Independent Autistic Intelligence.

• Independent. Fully local. The daemon runs on your machine, embeddings are computed locally, no telemetry, no cloud dependency. Your memory is your data and stays your data.
• Autistic. Describes the memory style, not a diagnosis or a metaphor. The memory is built around verbatim recall, attention to specific cues, and refusal to smooth rare events into typical ones. Most memory systems compress and summarize aggressively, aiming to give the assistant a gist of the past. This one preserves what was actually said and surfaces it on a precise cue. The trade-off is intentional: more storage and a stricter retrieval interface, in exchange for not losing details.
• Intelligence. Used in the systems sense, something that observes, adapts, and stays viable over time, not the marketing sense.

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Authors

By Areg Aramovich Noya, in collaboration with the team at lcgc.dev.

I built this because I needed it. It works for me. If it works for you, take it.

Acknowledgements

v0.2.0 — thanks to Reddit user u/BeginningReflection4 for the feedback and testing that shaped this release.

License

MIT

Contributing

Issues and PRs welcome. If your change touches retrieval, capture, or consolidation, include bench re-runs.