List the services published by a source that has a catalog (ArcGIS).

Service metadata: layers with their ids, extent, CRS, formats, limits, and the capabilities this source actually supports.

Describe a layer: fields with their types and coded-value domains, geometry type and record count. WMS sources publish no field schema and say so.

Query layer attributes and return GeoJSON in WGS84. Supports a SQL where, field selection, ordering and a bbox [minlon,minlat,maxlon,maxlat]. If exceededTransferLimit is true, repeat with offset. Only sources that declare the 'query' capability.

What is at a point: attributes at the given lon/lat (WGS84) for one or more layers of a source.

Render one source for a bbox [minlon,minlat,maxlon,maxlat] in WGS84 degrees and return it as an image. For several sources on one map use compose_map.

Legend of a source: structured entries (ArcGIS) or an image (WMS).

Compose one map from several sources, aligned, with a combined legend. Name a composition the profile declares, or list sources bottom-first. legend_mode is panel, below, separate or none — use 'separate' for rich geological keys. The bbox is lon/lat; projection, pixel grid and legend filtering are handled for you.