Skip to content

Installing OntoCode in VS Code

Multi-root workspaces: Only the first folder is indexed. Open your ontology project as a single-root folder, or put it first in a multi-root workspace.

  1. Install OntoCode from the Marketplace (v0.8.0+).
  2. File → Open Folder… and choose a directory with ontology files.
  3. Trust the workspace when prompted.
  4. Open the OntoCode activity bar and browse ontologies, classes, properties, individuals, and Diagnostics.

For a full walkthrough, see First success in 10 minutes.

Multi-root workspaces: Only the first workspace folder is indexed. Use a single-root folder or open the primary ontology project as the first folder.

Option B — GitHub Release VSIX (offline / air-gapped)

  1. Open GitHub Releases and download the latest ontocode-*.vsix.
  2. In VS Code: Extensions → … menu → Install from VSIX…
  3. Verify against SHA256SUMS — see release-integrity.md.
  4. Open a folder containing ontology files (.ttl, .obo, .owl, .rdf, .jsonld, .nt, .nq, .trig).

Release VSIX packages bundle ontoindex-lsp for Linux, macOS, and Windows.

Option C — Build from source

Prerequisites: Rust 1.88+, Node 20+, npm (see contributing.md).

From the repository root:

./scripts/package-extension.sh
cd extension && npx vsce package --no-dependencies

Install the generated .vsix via Install from VSIX…, or press F5 in VS Code with the extension/ folder open (Run Extension).

Option D — Language server on PATH

Use this only when the bundled server is missing or you are developing the LSP:

cargo install ontoindex-lsp --locked

Set OntoCode: Lsp Path (ontocode.lspPath) to the absolute path of your ontoindex-lsp binary. Trusted workspaces only — ignored in Restricted Mode.

Using the sidebar

After indexing, the OntoCode activity bar shows five views:

View What you see
Ontologies Indexed files and parse status
Classes Class hierarchy
Properties Object, data, and annotation properties
Individuals Named individuals
Diagnostics Lint issues; click to open source

Refresh — click ↻ on a view title, or run OntoCode: Refresh Explorer.

Re-index — run OntoCode: Index Workspace after adding or changing ontology files.

Click an entity name to open the Entity Inspector. For .ttl files, use the edit section to change labels, parents, or delete entities. See authoring.md.

Settings

Setting Default Description
ontocode.lspPath "" Trusted workspaces only. Path to ontoindex-lsp; ignored in Restricted Mode. Empty uses bundled binary
ontocode.queryHistoryLimit 20 Max entries in Query Workbench history
ontocode.reasoner.default el Default profile for Run Reasoner (dl/auto require OntoLogos 1.0)
ontocode.reasoner.autoProfile true Profile-detection warnings when running reasoner
ontocode.hierarchy.mode asserted Explorer hierarchy: asserted, inferred, or combined

Indexing runs on workspace open. ontocode.autoIndexOnOpen is a legacy setting (no-op).

Commands

  • OntoCode: Index Workspace — rebuild catalog
  • OntoCode: Refresh Explorer — refresh tree views (including diagnostics)
  • OntoCode: Open Query Workbench — SQL and SPARQL against indexed workspace (guide)
  • OntoCode: Open Manchester Editor / Add Manchester Axiom — complex class expressions (guide)
  • OntoCode: Run Reasoner — EL/RL/RDFS classification (guide)
  • OntoCode: Show Explanation — justification for unsatisfiable class
  • OntoCode: Set Hierarchy Mode — asserted / inferred / combined class tree
  • OntoCode: Open Class Graph / Property Graph / Import Graph / Neighborhood Graph — visualization (guide)
  • OntoCode: Create Class / Property / Individual — authoring in .ttl files
  • Problems panel — inline diagnostics from ontoindex-lsp after indexing
  • OntoCode: Show Entity Inspector / Jump to Source — from explorer context menu

Troubleshooting

Symptom Fix
Extension does not activate Open a supported ontology file or the OntoCode → Ontologies view
failed to start language server Run ./scripts/package-extension.sh, set ontocode.lspPath, or cargo install ontoindex-lsp
spawn ... ontoindex-lsp EACCES (macOS/Linux) Upgrade to OntoCode ≥ 0.4.0. Manual: chmod +x on the bundled binary path from the error
couldn't create connection to server Check Output → OntoIndex Language Server. Uninstall older OntoCode versions. Try cargo install ontoindex-lsp and set ontocode.lspPath
Empty explorer after open Run OntoCode: Index Workspace; check Output → OntoIndex Language Server
Inspector has no edit controls Entity must be in a Turtle (.ttl) file; other formats are read-only

See also troubleshooting.md, faq.md, and First success in 10 minutes.