Usage
These pages cover Arranger's configuration, query model, and integration options. If you're not sure where to start, the overview has pathway guidance by role.
Index mappings
An OpenSearch (or Elasticsearch) index mapping defines the fields in your documents and their types. Arranger reads the mapping at startup: it doesn't create or manage it. The mapping is typically created by a data ingestion pipeline (such as Maestro in the Overture platform) or uploaded directly to the search engine.
Catalogue configuration
Each catalogue in Arranger is controlled by four JSON configuration files. Together they define which index to connect to, how fields are labelled for display, which columns appear in the data table, and which fields are exposed as facet panels.
Query Processing
When a user applies filters in a search interface, the request flows through four main components:
GraphQL API
Arranger exposes a single GraphQL endpoint per server — the primary programmatic interface for searching a catalogue. A client combines a SQON filter with field selections, pagination, and sorting; Arranger translates the whole request into an Elasticsearch query and returns the results (see Query Processing for the end-to-end flow).
Building SQON queries
SQON is Arranger's query language: a small JSON format that describes a filter as a readable, portable tree structure. This guide walks you from the core idea through operator selection to practical TypeScript construction using the @overture-stack/sqon package.
SQONs In Detail
SQON is a JSON-based filter language Overture uses to describe query logic in a backend-neutral way, while retaining human readability and portability. This page focuses on the shape of a SQON itself: what nodes exist, what operators are supported, what aliases are accepted, and which edge cases matter when generating SQON programmatically.
Introspection API
Arranger exposes a set of read-only REST endpoints that describe the server's configuration and field structure at runtime. These endpoints are intended for tooling, LLM integration, and operator use: they do not require a GraphQL client and return plain JSON.
AI and automation
Arranger exposes its catalogue data and query tools to AI models, scripts, and pipelines through two surfaces: a REST introspection API and a dedicated MCP server. This page introduces both and points to where to go next.
Defaults and Limits
Arranger applies default values when a query argument, download request, or environment variable is left unset. Most of these defaults are enforced in resolver and middleware code rather than declared on the GraphQL schema itself, which means they are not visible through introspection: a client, code generator, or AI agent that only inspects the schema will not discover them. This page is the single reference for all of them.
Feature Flags
Arranger ships a set of boolean feature flags that turn optional behaviour on or off. Each can be set two ways: