Product · API & Playground

Ship to your stack on day one.

Five endpoints. Five output formats. Tag pinning, language negotiation, scheme scoping. The Playground in the app generates every call — copy as cURL or fetch and paste into your codebase.

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Endpoints

Five endpoints, no more, no less.

We resisted the urge to ship twenty. Most consumer pipelines call three of these.

Verb	Path	Returns
GET	/v1/ontologies/:id/concepts	Every concept in an ontology, optionally scoped to a scheme.
GET	/v1/ontologies/:id/relations	All relations with their typed endpoints and relation type.
GET	/v1/ontologies/:id/schema	The T-Box — every class with attributes plus relation types with domain / range.
GET	/v1/ontologies/:id/concepts/:conceptId	One concept — full SKOS labels, definitions, properties, deprecation pointer.
POST	/v1/ontologies/:id/sparql	SPARQL query against the ontology (read-only).

Try it

The playground, right here.

Switch endpoints. Toggle parameters. The URL and JSON response update live — no signup, no auth, no real network call. Copy as cURL when you're ready.

List concepts in the Cars ontology, scoped by scheme + tag + language.

Tag

Language

Format

GEThttps://api.semlify.com/v1/ontologies/cars/concepts?tag=v1.3&lang=en&format=json

200 OK · application/json

22 lines · 381 chars

{
  "ontology": "cars",
  "tag": "v1.3",
  "lang": "en",
  "total": 397,
  "returned": 2,
  "truncated": true,
  "data": [
    {
      "id": "c_camry",
      "prefLabel": "Toyota Camry",
      "manufacturer": "c_toyota",
      "tag": "v1.3"
    },
    {
      "id": "c_corolla",
      "prefLabel": "Toyota Corolla",
      "manufacturer": "c_toyota",
      "tag": "v1.3"
    }
  ]
}

Response computed live from your selections — no real network call.

Tag pinning

Pin your pipeline to a known-good state.

Add `?tag=v1.3` to any read endpoint. Your RAG pipeline gets a stable snapshot — no behavior shifts when a maintainer adds a concept, no surprise breakage on Monday morning. Re-index when you choose to, on `tag.created` webhooks.

Pinned read

bash

# Pin to a tagged snapshot
curl https://api.semlify.com/v1/ontologies/cars/concepts \
  ?tag=v1.3 \
  &lang=en \
  &format=jsonld \
  -H "Authorization: Bearer $TOKEN"

# Roll forward by changing one query param
curl ".../concepts?tag=v1.4&lang=en&format=jsonld"

Format negotiation

JSON, JSON-LD, SKOS Turtle, OWL XML, CSV.

One endpoint, five outputs. Pick whichever your downstream tool consumes natively. The full ontology export round-trips OWL — your architects can open the same artefact in Protégé.

Format selection

bash

# JSON-LD for a RAG pipeline
curl ".../concepts?format=jsonld"

# SKOS Turtle for a search index
curl ".../concepts?format=skos"

# OWL RDF/XML for Protégé / Stardog
curl ".../schema?format=owl"

# CSV for ad-hoc analysis
curl ".../concepts?format=csv"

Try the playground.

Generate every call against your own data. Copy as cURL, fetch, or Python.

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