API Reference

This section is the endpoint-by-endpoint reference for the Cloud Content Repository APIs used by the Enterprise Context Engine (ECE). Each operation page lists its parameters, request and response schemas, status codes, and tested request and response examples.

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Base URL and Authentication

All operations are served from your Cloud Content Repository environment:

https://{environment_id}.content-lake.ai.experience.hyland.com

Every request needs an OAuth 2.0 bearer token in the Authorization header. See Authentication for how to get a token and which permissions each API group needs.

Header	Required	Description
Authorization	Yes	Bearer <access_token>
Accept	No	application/json or application/vnd.hxcs.v1+json for JSON endpoints; */* for downloads and pre-signed URLs
HXCS-REPOSITORY	No	Repository ID. Defaults to default

Most APIs return errors in this body shape:

{
  "entity-type": "exception",
  "status": 400,
  "message": "Unsupported predicate operator: eq"
}

The ECE Graph Query APIs use their own shape, {"code", "message", "details", "traceId"}, with stable codes such as ECE-404-NOT_FOUND. See the Error Reference for status codes and common causes.

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The reference is generated from the curated ECE Cloud Content Repository OpenAPI specification (openapi/ece-content-lake-curated-api.json). It covers 27 operations in seven groups.

Query API

Search documents in the Cloud Content Repository with HXQL, the Hyland query language:

• Document Query: Run an HXQL query, with searchAfter cursor paging beyond 10,000 results
• Advanced Query: Build a query from parameterised predicates and quick filters
• Vector and Hybrid Search: Find the chunks nearest to a query vector, optionally combined with full-text terms and an HXQL document filter
• Terms Aggregation: Count documents per property value
• Indexing: Wait for full-text indexing to catch up after writes

Embeddings API

• Embedding Lookup: Get a single embedding with its text and location in the source document

Download API

Get the original file behind a document:

• Stream: Download a blob, with range requests, conditional requests, and digests
• Pre-signed URL: Get a time-limited URL (up to 3600 seconds) that can be shared with clients

Ontology API

Define how content is mapped into the Knowledge Graph:

• Ontologies: List, upload, download, and delete YAML ontologies
• Graph Configuration: Read a graph database's configuration and ontology routes
• Ontology Routes: Decide which ontology applies to which documents

GraphDB API

Manage graph databases:

• Graph Databases: List, create, inspect, and delete v1 (deprecated, DQL) and v2 (GraphQL, ACL-enforced) graph databases
• Aggregate: Count the entities of a type by a groupable property (v2 graph databases)

Graph Rebuild API

Rebuild graph metadata:

• Rebuild Jobs: List, start, and track jobs that re-evaluate ontology routes over matching documents

ECE Graph Query API

Retrieve Business Objects from a graph database. Every path starts with /api/ece/business-objects/{graphDBId}, and each operation requires the content-lake-api.graphs.read permission:

• Search Business Objects, Get a Business Object, Related Business Objects, Shared Attributes, and Shared Attribute Provenance

Operations covered in the tutorials

These operations are available but are not part of the curated specification. They are documented with tested examples in the tutorials:

Operation	Tutorial
Named queries (GET /api/query/named, GET /api/query/named/{namedQuery}, POST /api/query/named)	Querying with HXQL
Blob headers (HEAD /api/download/...)	Downloading Content

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Next Steps

• Getting Started - Set up access and make your first calls
• Authentication - Tokens, claims, and permissions per API
• Tutorials - Task-based guides for querying, search, downloads, and the Knowledge Graph
• Error Reference - Error format, status codes, and troubleshooting