OntoCode

OntoCode brings OWL/RDF ontology editing into VS Code and Git — browse classes, edit Turtle, run EL reasoning, and validate in CI without Protégé.

OntoIndex is the Rust engine behind it: a local CLI and language server that indexes your workspace and exposes SQL, SPARQL, and patch APIs.

Start here: Documentation — Start here · First success tutorial · cargo install ontoindex-cli. You do not need to clone this repo.

Naming: OntoCode is the VS Code extension (product UI). OntoIndex is the Rust engine (ontoindex CLI, ontoindex-* crates, ontoindex-lsp). This repo contains both.

Documentation: Read the Docs — What ships today

Choose your path

Use the CLI (OntoIndex)

cargo install ontoindex-cli
ontoindex query /path/to/your/ontologies "SELECT * FROM classes"
ontoindex validate .

Note: ./fixtures exists only in a git clone. After cargo install, point at your own ontology folder (see getting started guide).

From a clone, cargo run -- runs the ontoindex binary (workspace default-member is ontoindex-cli):

cargo run -- query fixtures "SELECT * FROM classes"

Use VS Code (OntoCode Explorer)

1. Install OntoCode from the Marketplace, or download a VSIX from GitHub Releases.
2. Open a folder with .ttl, .owl, .rdf, or other supported ontology files.
3. Use the OntoCode activity bar to browse entities, edit in the inspector, and open diagnostics.

Full install and troubleshooting: install guide. Editing guide: authoring guide.

Two-layer architecture

OntoCode is designed as two products that ship together:

┌─────────────────────────────────────┐
│  OntoCode (v0.6.0)                  │
│  VS Code extension + explorer UI    │
└─────────────────┬───────────────────┘
                  │ ontoindex-lsp (stdio)
┌─────────────────▼───────────────────┐
│  OntoIndex (v0.6.0)                 │
│  Rust index, catalog, query, CLI, LSP │
└─────────────────┬───────────────────┘
                  │ Oxigraph / Horned-OWL / OntoLogos
┌─────────────────▼───────────────────┐
│  Your ontology repo                 │
│  .ttl .owl .rdf .jsonld …           │
└─────────────────────────────────────┘

OntoIndex is useful on its own today (CLI, CI, local analysis). The extension calls into the same engine via a language server rather than reimplementing ontology logic in TypeScript.

What ships in v0.6.0

See the full capability matrix: What ships today (updated each release).

Earlier releases: Changelog · CHANGELOG.md on GitHub.

Why OntoCode?

Protégé is strong for traditional ontology editing, but most engineering teams live in Git, pull requests, and VS Code. OntoCode targets that workflow:

Long-term goal: Protégé-competitive OWL 2 DL + OBO maintenance in VS Code — see Protégé parity checklist.

Quick start

See Start here or First success in 10 minutes for the canonical onboarding path.

# From a git clone
cargo build --release
cargo run -- inspect fixtures
cargo run -- query fixtures "SELECT * FROM classes"
cargo run -- validate fixtures

# Installed CLI (use your ontology path, not ./fixtures)
cargo install ontoindex-cli
ontoindex query /path/to/ontologies "SELECT * FROM classes"
ontoindex validate /path/to/ontologies

Reasoning (v0.6)

• EL / RL / RDFS classification via OntoLogos 0.9.0
• CLI: ontoindex classify, ontoindex explain
• LSP: ontoindex/runReasoner, ontoindex/getExplanation
• Explorer hierarchy mode: asserted / inferred / combined

See reasoner guide. DL and auto profiles require OntoLogos 1.0.

Coming in v0.7+

The extension is a thin TypeScript shell over ontoindex-lsp and the OntoIndex crates — not a second ontology stack. v0.7a introduces a React + Vite webview layer for panels (inspector, query workbench, graphs, reasoner); see React UI integration plan.

Roadmap

See roadmap, product plan, and Protégé parity checklist for the full product plan.

Built on

OntoIndex delegates to mature Rust libraries — see dependency matrix.

Policy: ADR-0016. Third-party licenses (including LGPL for horned-owl): LICENSES.

Repository layout

crates/
├── ontoindex-core      # types, workspace scanner
├── ontoindex-parser    # RDF parsing and entity extraction
├── ontoindex-owl       # Horned-OWL facade, patch write-back, Manchester (v0.5)
├── ontoindex-catalog   # index builder and semantic catalog
├── ontoindex-diagnostics # lint rules and diagnostic collection
├── ontoindex-query     # SQL-like and SPARQL engines
├── ontoindex-reasoner  # OntoLogos EL/RL/RDFS classification (v0.6)
├── ontoindex-cli       # `ontoindex` binary
└── ontoindex-lsp       # language server for OntoCode
extension/              # VS Code extension (OntoCode Explorer)
fixtures/               # sample ontology for tests
scripts/                # extension packaging helpers
docs/                   # user guides (install, SQL, LSP API)
docs/design/            # product specs, ADRs, wireframes, backlog
examples/               # Rust examples and query cookbook
tests/                  # integration and golden snapshot tests

Virtual tables

Column schemas: SQL reference. SPARQL: SPARQL reference. LSP methods: LSP API. Workspace limits: workspace limits.

API stability (pre-1.0)

Published ontoindex-* crates are at 0.6.x. Library APIs, LSP wire JSON, and SQL virtual table columns may change between minor releases until v1.0 stable core is complete. The CLI validate and classify exit codes are documented in workspace limits.

Development

See CONTRIBUTING.md or the contributing guide. Quick checks:

cargo build -p ontoindex-lsp --bins
cargo test --workspace
cd extension && npm ci && npm test
cargo fmt --all
cargo clippy --workspace --all-targets --all-features -- -D warnings

Update golden snapshots:

ONTOINDEX_UPDATE_GOLDEN=1 cargo test golden_classes

Installing from releases

Pre-built artifacts on GitHub Releases:

• ontoindex CLI (Linux x64)
• ontoindex-lsp per platform (Linux, macOS, Windows)
• ontocode-*.vsix (VS Code extension)

Verify downloads: release integrity. Maintainer release process: releasing guide.

Workspace crates publish to crates.io on each v0.6.x release tag: ontoindex-core, ontoindex-parser, ontoindex-owl, ontoindex-diagnostics, ontoindex-catalog, ontoindex-query, ontoindex-reasoner, ontoindex-lsp, ontoindex-cli.

See CHANGELOG.md for release notes. Security: security policy.

License

MIT OR Apache-2.0. Third-party licenses: LICENSES.