plexus (_graph)

A typed, on-prem knowledge graph for AI agents. Read-only for humans, write-only for agents, spoken over the Model Context Protocol.

Part of the pcas.io product line.

TL;DR

Knowledge management has been a document sport for twenty years — folders, notes, wikis, editor wars. plexus inverts that.

In plexus, every piece of information is a typed entity — concept, decision, fact, project, task, document, skill, … — with hard, temporally-valid edges between them. No free-form text, no forgotten tags, no "I'll clean that up later." Writing and linking happen exclusively through MCP — from your agent. The dashboard shows you the graph; it has no edit buttons.

That gets you three things:

1. Your agent doesn't have to ask you — it just builds, with strict kind-and-relation discipline.
2. The graph never goes stale, because lint, supersede, and provenance are part of the workflow.
3. You can share a single idea, not your graph — passkey-gated one-shot links that burn on first click.

Runs in Docker Compose on your own hardware. Apache-2.0 licensed.

Think of it as a wiki, but for LLMs

Traditional wikis are built for human readers: free-form prose, hand-curated links, a tree of pages that rots the moment you stop grooming it. Put an LLM in front of one and the first thing the LLM does is ask you to summarise it.

plexus reverses the audience. The LLM is the reader and the writer. Each page is a typed record instead of a paragraph, each link is a named relation instead of a hyperlink, and each edit is an atomic MCP call instead of a markdown diff. The UI shows you the same graph your agent sees — but your agent does the curation.

This is the same pattern Andrej Karpathy sketched in his "The LLM wiki" gist (April 2026, 5000+ stars): instead of stateless RAG against raw documents on every query, an LLM compiles knowledge into a structured, cross-referenced wiki once and keeps it up to date. plexus is that pattern on infrastructure:

Karpathy calls the gist an "idea file" — a vendor-neutral prompt pattern. plexus gives it a production backend: typed storage, optimistic locking, temporal edges, multi-user auth, audit log.

What that buys you:

• One source of truth across sessions. Your agent loads the context at the start of every conversation. You don't re-explain yourself.
• One source of truth across agents. Claude web, Claude Code, Claude Desktop, Le Chat, Gemini — whoever connects speaks the same graph.
• One source of truth across humans. Multi-user out of the box, scoped tokens per person, shared project containers, audit log.

Contents

Understand it

• Use cases — seven concrete scenarios plexus is built for

Run it

• Quickstart — Docker Compose up in under two minutes
• Create your admin user (first run) — the bootstrap walk-through, including where to find the admin token

**

... View full README on GitHub