graymatter

AI agents forget everything between sessions. GrayMatter gives them persistent memory, a self-building knowledge graph, and cuts context tokens by 90%. One binary. Drop it in. Run it. No Docker, no databases, no config files, no cloud accounts, no bullshit. General-purpose MCP server. Zero vendor lock-in. Works with Claude Code, Cursor, Codex, OpenCode, Antigravity — and any MCP-compatible client. Also a plain Go library if you don't use MCP. Free. Offline. No account required.

Why

Every AI agent is stateless by default. Each run re-injects the full conversation history — and that history grows linearly. Two prompts in and you've already burned half of your daily quota.

That's not just a memory problem. That's a money and performance problem.

Mem0, Zep, Supermemory solve this — but they're Python/TypeScript-only and require a running server. The Go ecosystem has no production-ready, embeddable, zero-dependency memory layer for agents.

That gap is GrayMatter.

Knowledge Graph

Your agent doesn't just remember facts — it builds a map of how they connect.

Run the daemon with --kg and every consolidation cycle extracts typed entities (person, organization, project) and links the ones that appear together. No manual tagging. No configuration. The graph builds itself from ordinary use.

graymatter daemon run --kg    # that's it — the graph builds itself

The graph as one self-contained page — inline force-directed SVG, zero external assets, works offline. Hover any edge to see the fact IDs that produced it:

graymatter kg render --out graph.html
graymatter kg render --out graph.dot    # Graphviz, for your own layout
graymatter doctor --graph --html        # analytics + this render in one go

Watch it build, one frame per session:

scripts/kg-timelapse.sh    # deterministic corpus -> frames -> GIF
                           # or anywhere: scripts/Dockerfile.kg-timelapse

Observability

You can't improve what you can't see.

graymatter tui opens a live terminal dashboard with everything your agent memory is doing — no extra setup required.

What you get at a glance:

• Facts — total stored, distributed across agents
• Memory cost — KB on disk (text + embeddings), not tokens
• Recalls — cumulative access count across all sessions
• Health — percentage of facts above relevance threshold (weight > 0.5)
• Token cost (30d) — real spend breakdown by model, with cache hit rate
• Agent activity — facts vs recalls per agent, side by side
• Weight distribution — how consolidated your memory is over time
• Activity timeline — facts created per day, last 30 days

The dashboard auto-refreshes every 5 seconds. Press 1–4 to switch tabs, r to force refresh, q to quit.

graymatter doctor --graph extends visibility to the knowledge graph itself: hubs by degree, articulation points, orphans, and a declared connectivity ratio — printed or emitted as JSON.

What GrayMatter gives you

Quick start

Install and see it working in under a minute — no API keys, no Ollama:

go install github.com/angelnicolasc/graymatter/cmd/graymatter@latest
graymatter demo              # a working store with 3 agents, then the TUI opens
graymatter init              # wire YOUR project: MCP config + memory block
graymatter init --hooks      # Claude Code: memory injected every turn
graymatter doctor            # read-only observations of local setup artifacts

Standard doctor does not write a probe, start a daemon, execute a binary on PATH, or test whether the data directory is writable. Its config checks find references in files; they do not prove which settings a client loaded. In JSON, ok means no check failed, while readiness: not_evaluated keeps readiness separate from the observations. The --health, --graph, --audit, and --embeddings modes have separate contracts; graph rendering can write HTML.

graymatter init --global still performs that normal setup in the current directory. It additionally installs the managed memory instructions in Claude Code and OpenCode's home-scoped instruction files. It does not globalize project-scoped MCP configs. If Claude's MCP server is already registered at user scope and the instructions are already available globally, you do not need to repeat local client setup in each repository. For a new user-scoped Claude MCP registration, run once:

claude mcp add --scope user --transport stdio graymatter -- graymatter mcp serve

To prepare only the current project's memory directory before a session, use graymatter init --store-only in a build containing this Unreleased change; the v0.19.1 binaries listed below do not include it. It creates .graymatter/MEMORY.md if needed and leaves an existing regular .graymatter/gray.db untouched. It does not write client configs, instructions or hooks, change PATH, open the database, or verify runtime health. If neither leaf is regular, symlink or other nonregular MEMORY.md/gray.db entries cause an error; use --dir to select the real data directory. You can repeat it safely:

graymatter init --store-only --quiet

For launchers that find the Git checkout or worktree root before running this command, see the Claude Code examples. Global hooks are optional (graymatter hooks install --scope global) and skip unprepared directories. MCP can itself create gray.db when it starts, even without init --store-only; this command does not prevent that behavior. Project-scoped clients still need their own MCP config. Codex is the exception in the table below because its MCP config is already home-scoped.

For a new, opt-in guarded Claude user registration, use --no-create and prepare each selected checkout before connecting:

claude mcp add --scope user --transport stdio graymatter -- graymatter mcp serve --no-create
cd /path/to/selected/project
graymatter i