MCP Server · RDF/SPARQL · Open Source

Your codebase as a
knowledge graph

Most MCP servers give AI tools.
OpenTology gives AI understanding — persistent memory, dependency awareness, and impact analysis across every session.

GitHub npm
$ npm install -g opentology click to copy
Scroll to explore
OpenTology scanning itself — 67 modules, 234 call relations

Stats

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Modules
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Symbols
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Calls
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Sessions

Legend

  • Commands
  • Libraries
  • MCP Server
  • Classes / Interfaces
  • Call Relations
  • Templates / Tests

Node Detail

Click a node to inspect

Sessions

Why OpenTology?

Not just tools — a fundamentally different way for AI to understand your project.

🧠

Persistent Memory

Sessions with activities, todos, and insights persist in an RDF graph. Decisions, issues, and knowledge carry across every conversation.

💥

Impact Analysis

Before editing, AI checks the dependency graph to understand blast radius. No more accidental breakage of dependent modules.

🔍

6 Language Support

Symbol-level scanning for TypeScript, Python, Go, Rust, Java, and Swift. Classes, functions, methods, and call graphs.

⚡

Zero Docker

Oxigraph runs as WebAssembly. No containers, no native builds. Works everywhere Node.js runs.

🤖

Behavioral Instructions

Automatically injects CLAUDE.md so AI checks impact, searches context, and records decisions without being asked.

🌐

Standard-Based

Built on RDF, SPARQL, RDFS reasoning, and SHACL validation. Query your graph with any SPARQL-compatible tool.

See the difference

Real experiment on this codebase. Watch both approaches run.

"What breaks if I change store-adapter.ts?"

grep / ripgrep
OpenTology
6x
fewer tool calls
6 calls → 1 call
6x
less token usage
~2.1k → ~350
+29%
more results found
7 files → 9 dependents

Memory that persists

Every session is a first-class citizen in the graph. AI picks up exactly where it left off — every time.

Session Lifecycle
▶
Session Start
context_load
Loads recent sessions, open issues, and decisions. AI immediately knows the project state — no re-explaining needed.
⚡
During Work
context_impact · query · push
Check blast radius before editing. Search past decisions. Record new knowledge and architecture choices as they emerge.
✓
Session End
push (otx:Session)
Commits a session summary — what was done, what’s next, insights learned — into the persistent graph.
context_load
Recent Sessions
v0.4.0 release — proactive session save + README update
CJK escape bug fixed · CLAUDE.md compressed to 84 lines → Next: structured session schema follow-up
Open Issues
No open issues ✓
Recent Decisions
WASM-only embedded storage for zero-docker setup
2,868 context triples · 101 session triples · loaded in 42ms

Get Started in 30 Seconds

Three commands. That's it.

1

Add to MCP config

Point your AI assistant to OpenTology.

"command": "npx",
"args": ["-y", "opentology", "mcp"]
2

Initialize

Creates graph, hooks, and AI instructions.

opentology context init
3

Scan codebase

Builds the knowledge graph from your code.

opentology context scan