memex: trusted engineering context for agentic software engineering
Open-source MCP server and hook service that keeps Claude Code and Codex engineering context current as the code changes, and holds edits whose evidence changed.
A daemon, hook service and MCP server that turn commits and file changes into structured engineering knowledge and deliver it to agents with freshness and provenance preserved, without making memex a source of personal memory or raw session state.
memex builds a bitemporal knowledge graph of your repository (modules, symbols, decisions, problems, evidence, and code evolution). In v1 it also hooks into Claude Code and Codex: each session starts with the right context, each edit is checked against the current code, and the agent is told exactly what changed.
Where memex lives
Evaluation record in BENCHMARK.md, release history in CHANGELOG.md, reporting process in SECURITY.md, and how to work on it in CONTRIBUTING.md.
https://github.com/user-attachments/assets/b14e3185-ea36-4ae5-bd18-2d34e6bf7be4
memex v1 in 60 seconds. If the player does not load, download the video.
Live context (v1)
Coding agents work from a snapshot of the code. A teammate pushes, another agent edits a file, a branch moves, and the agent keeps acting on what it read earlier. v1 keeps that snapshot current, inside Claude Code and Codex:
uv tool install memex-mcp # installs the `memex` command
cd your-repo
memex v1 doctor # what is set up, what is missing, what to do next
memex v1 install claude # hooks in .claude/settings.json; global settings untouched
memex v1 install codex --neo4j-uri bolt://localhost:7687 # optional, for Codex
memex needs a Neo4j 5 server you already run (Docker is not required). Hooks go only into the checkout's own project configuration, and memex never asks for or stores your client credentials. Full guide, host recipes and rollback: docs/v1/25_ONBOARDING.md.
flowchart LR
A[Your repository<br/>files + git] --> B[memex watcher<br/>tree-sitter + Gemini]
B --> C[Neo4j graph<br/>bitemporal facts]
C --> D[memex core<br/>ContextPacket selection]
D --> H[Hook service<br/>session start · edit checks · resume notice]
D --> E[Hermes MemoryProvider<br/>automatic read-only prefetch]
D --> F[MCP tools<br/>explicit lookup]
H --> G[Claude Code / Codex]
E --> G
F --> G
style B fill:#cfe8ff,stroke:#0066cc,color:#000
style C fill:#fff4cf,stroke:#cc9900,color:#000
style H fill:#d4f5d4,stroke:#2d8f2d,color:#000
Install
Via Claude Code marketplace
/plugin marketplace add STiFLeR7/claude-plugins
/plugin install memex-mcp@stifler-marketplace
Restart your Claude Code session.
The first start after installing or upgrading downloads memex's Python dependencies (about 40 seconds), which can exceed Claude Code's MCP connect timeout once. Warm it up first, then restart:
npx -y stifler-memex-mcp --help # one-time download; later starts take a few seconds
If Claude Code still shows a connection timeout, open /mcp and reconnect
memex. If a tool says memex cannot reach Neo4j, start Neo4j (for example
docker start memex-neo4j); the tools recover without a restart.
Manual
docker compose -f docker/docker-compose.yml up -d
cat > .env <<EOF
NEO4J_URI=bolt://localhost:7687
NEO4J_USER=neo4j
NEO4J_PASSWORD=memex-local
GEMINI_API_KEY=your-key-here
EOF
npx stifler-memex-mcp init --repo .
npx stifler-memex-mcp watch --repo .
npx stifler-memex-mcp serve --repo .
Hermes integration
The Hermes integration is read-only. Hermes retains personal memory, raw
session state, and execution state. memex supplies repository engineering
context through a bounded ContextPacket; it does not ingest Hermes
state.db, transcripts, prompts, or tool results.
Add the memex provider to Hermes' profile configuration:
memory:
provider: memex
plugins:
memex:
repo_path: /absolute/path/to/repository
prefetch_timeout_seconds: 7
max_items: 8
max_chars: 12000
If Hermes is not installed, use the same context selector through the MCP
get_engineering_context tool. Both paths share the protocol-neutral memex
core and fail open when retrieval is unavailable.
Self-hosted team deployment
For a shared team setup (one Neo4j + one memex-server, auth on by default, Neo4j's ports never exposed to the host):
bash docker/bootstrap-team-env.sh
docker compose -f docker/docker-compose.team.yml up -d
See docker/TEAM-DEPLOY.md for the full flow, capturing the
initial admin key, and the down -v footgun to avoid.
At a glance
The lifecycle
flowchart TD
Init[memex init<br/>extract baseline] --> Watch[memex watch<br/>daemon + git hooks]
Watch -->|commit| Extract[tree-sitter extract<br/>symbols, imports, lockfile]
Extract --> Synth[Gemini Flash<br/>diff → Decision nodes]
Synth --> Write[Graphiti add_episode<br/>+ post-hoc bitemporal SET]
Write --> Decay[Scheduler<br/>nightly confidence decay]
Decay -->|stale edges| Archive[expired_at = now]
Serve[memex serve<br/>MCP stdio/HTTP] -.->|reads| Write
Agent[AI agent] -->|14 MCP tools| Serve
Serve -->|record_decision / record_problem| Write
Cluster[memex cluster<br/>Leiden over hybrid edges] -.->|every N commits| Write
style Init fill:#e8f4ff,color:#000
style Watch fill:#fff4cf,color:#000
style Synth fill:#ffe0cc,color:#000
style Serve fill:#d4f5d4,color:#000
MCP tools
14 tools: eight read, four write, two analytic.
Read
Write
Bitemporal confidence
Confidence is not a stored number that mutates. It is computed at query time from base_confidence, validation status, time since last reinforcement, and access count.
flowchart LR
Edge[Edge created<br/>base_confidence] --> Q{Validated by<br/>a human?}
Q -->|yes| Slow[Slow regime<br/>half-life ~139d]
Q -->|no| Fast[Fast regime<br/>stale at exactly 30d]
Slow --> Score[Composite score<br/>conf × recency × rehearsal]
Fast --> Score
Score -->|below floor| Stale[get_stale_context surfaces it]
Score -->|access| Bump[last_reinforced_at updated]
Bump --> Score
style Slow fill:#d4f5d4,color:#000
style Fast fill:#ffd4d4,color:#000
Hierarchical clusters
memex cluster runs hierarchical Leiden over a hybrid edge graph:
Measure Your Savings
memex tracks token reduction metrics and human review actions locally in a SQLite database (~/.config/memex/telemetry.db).
You can query your savings at any time using the CLI:
memex stats
Or view the raw JSON payload:
memex stats --json
Or target a specific repository scope:
memex stats --repo /path/to/repo
This returns an aggregation of:
- Period Summaries: Calls, tokens returned, naive tokens (size of files requested), tokens saved, and token reduction percentage across
today,last 7 days,last 30 days, andlifetime. - Top Tools: The most valuable tools sorted by total tokens saved.
- Agent Clients: Active agents (Claude Code, Gemini CLI, Cursor, Codex) and their token saving distribution.
- Validation Health: Total validated, unvalidated, and corroborated nodes, along with the elapsed days since the last review.
The same statistics are exposed via the HTTP MCP transport:
GET /stats?repo=/path/to/repo
Authorization: Bearer <your-key>
Connect your agent
Marketplace install above does this for you. Manual wiring in .claude/settings.json:
{
"mcpServers": {
"memex": {
"type": "stdio",
"command": "npx",
"args": ["-y", "stifler-memex-mcp", "serve", "--repo", "."]
}
}
}
Add to ~/.cursor/mcp.json:
{
"mcpServers": {
"memex": {
"command": "npx",
"args": ["-y", "stifler-memex-mcp", "serve", "--repo", "."]
}
}
}
Add to ~/.gemini/settings.json:
{
"mcpServers": {
"memex": {
"command": "npx",
"args": ["-y", "stifler-memex-mcp", "serve", "--repo", "."]
}
}
}
Add to ~/.codex/config.toml:
[mcp_servers.memex]
command = "npx"
args = ["-y", "stifler-memex-mcp", "serve", "--repo", "."]
memex can back Claude's native memory tool: agents read from a per-session graph projection plus a writable scratch zone.
memex memory-tool serve --repo . # in-process
memex memory-tool serve --repo . --transport http # FastAPI on :7464
from memex.memory_tool import MemexAsyncMemoryTool
memory_tool = MemexAsyncMemoryTool(repo_root=".")
client.beta.messages.run_tools(..., tools=[memory_tool])
Operating principles
When to use memex
Project structure
memex/
├── memex/
│ ├── extractor/ tree-sitter + lockfile parsers
│ ├── graph/ Neo4j writes, confidence, archive, cluster engine
│ ├── synthesizer/ Gemini Flash → Decision nodes
│ ├── mcp_server/ 14 MCP tools (read + write + analytic)
│ ├── memory_tool/ Anthropic memory_20250818 adapter
│ ├── watcher/ daemon + git hooks
│ └── cli.py init / watch / serve / review / graph / cluster
├── tests/ unit, integration, and objective evaluation suites
├── docker/ Neo4j compose
├── npm/ npx wrapper (publishes as stifler-memex-mcp)
└── Dockerfile introspection-only image for MCP directory sandboxes
Commands
License
MIT. See LICENSE.
Author
Hill Patel (@STiFLeR7)
Core Contributors & Maintainers
- Hill Patel (@STiFLeR7), architect and maintainer
- Nirvaan Lagishetty (@Nirvaan05), lead contributor and maintainer
Contributing
Open an issue or PR. uv sync --all-extras installs the development toolchain.
Run uv run pytest -m "not integration" for the offline suite and uv run ruff check . before opening a PR. Version bumps must update pyproject.toml,
npm/package.json, server.json, and the team Docker image tag together.
Release history is in CHANGELOG.md. The v1 design and
evaluation records are under docs/v1/, and the v0.9 architecture
under docs/architecture/v0.9/.
Vannevar Bush, 1945: "Consider a future device for individual use, which is a sort of mechanized private file and library. It needs a name, and to coin one at random, memex will do."
