See the API's various operations for details on their request parameters and response data:

OperationMethodEndpoint
Sites
List sitesGET/sites
Create a new sitePOST/sites
Remove a siteDELETE/sites/​{siteId}
Get a siteGET/sites/​{siteId}
Update a sitePUT/sites/​{siteId}
List nodes per siteGET/sites/​{siteId}/​nodes
Attribute types
List attribute typesGET/attribute-types
Create a new attribute typePOST/attribute-types
Get settingsGET/attribute-types/​settings
Update settingsPUT/attribute-types/​settings
Remove an attribute typeDELETE/attribute-types/​{attributeTypeId}
Get an attribute typeGET/attribute-types/​{attributeTypeId}
Update an attribute typePUT/attribute-types/​{attributeTypeId}
Nodes
List nodesGET/nodes
Create a new nodePOST/nodes
Get a node boot imageGET/nodes/​boot-medium
Remove a nodeDELETE/nodes/​{nodeId}
Get a nodeGET/nodes/​{nodeId}
Update a nodePUT/nodes/​{nodeId}