open-ontologies

Name: open-ontologies Review
Item: open-ontologies
Rating: 3.0
Author: Aaron Matthews

Skill Development Usable

AI-native ontology engine: a Rust MCP server with tools for building, validating, querying, and reasoning over RDF/OWL ontologies. In-memory Oxigraph triple store, native OWL2-DL tableaux reasoner, SHACL validation, SPARQL, versioning. Single binary, no JVM.

Generate RDF ontologies from business domain descriptions and validate them automatically.
Query knowledge graphs with SPARQL to find relationships between data entities across systems.
Validate data quality against ontology rules using SHACL before loading into production.

116 starsMIT (commercial OK)FreeQuick setup

Usable rating — This tool is functional but has notable gaps. Review the evaluation notes below before deploying.

Why it matters

Eliminates JVM overhead and deployment friction for teams needing semantic reasoning at scale. Native OWL2-DL reasoning with SHACL validation reduces data quality incidents and enables knowledge graph automation without external services.

Best for

Data engineering teams building knowledge graphs or semantic data pipelines requiring fast, validated ontology reasoning.

Works in

Claude Code Claude Cowork Claude Chat

Source

https://github.com/fabio-rovai/open-ontologies

By fabio-rovai

How to Get It

Option 1: Claude Desktop App (Code Mode)Click the + button next to the prompt box → Plugins → Add plugin. Search and click Install. Skills work in Claude Code only.

Option 2: Paste into Claude CodeCopy the command below and paste it into your conversation. Claude will install it.

Command

claude plugins install fabio-rovai/open-ontologies

Tip: Paste this into a Claude Code conversation. Verify command matches your Claude Code version.

CostFree

Trust Signals Auto-scanned

Stars116Last updated2026-05-12LicenseMIT (OK for commercial use)Known CVEsNone foundSources: GitHub Advisory Database + OSV.dev · Scanned 2026-05-21 · scanner v1

Community Pulse Active

Discussed on Hacker News, Reddit

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21 mentions across 2 sources

Reviewer notes

Auto-scanned review. These are observations, not a security certification.

Scored from trust signals (evidence-eval-v1): 116 GitHub stars; contributors unknown; last commit 9d ago; license MIT.

How to evaluate tools before deploying →

Data shown here comes from public APIs and automated scanning. Reviewer notes reflect one person's experience. This is not a security certification or legal recommendation. Always evaluate tools according to your own organization's policies.

Evaluation Scores

Evaluation

Ease of Use

3/5

Versatility

3/5

Reliability

3/5

Security

3/5

Overall score3.00 / 5.00 UsableEvaluatedMay 2026

Scored from trust signals (evidence-eval-v1): 116 GitHub stars; contributors unknown; last commit 9d ago; license MIT.

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