Working with services you've published
The ArcGIS REST API, short for Representational State Transfer, provides a simple, open web interface to ArcGIS. A major portion of the API, described in this section of the help, allows access to services hosted by ArcGIS for Server.
All resources and operations exposed by the REST API are accessible through a hierarchy of endpoints or Uniform Resource Locators (URLs) for each GIS service published with ArcGIS for Server. When using the ArcGIS services portion of the REST API, you typically start from a well-known endpoint, which represents the server catalog. See the Resource hierarchy to learn about how the services in the REST API fit together under the catalog.
The default REST endpoint for an ArcGIS Server site is as follows:
http://<host>:/arcgis/rest/services
For example, to get to the root directory of ArcGIS Online services, the URL is as follows:
http://server.arcgisonline.com/arcgis/rest/services
From this base URL, you can navigate to any of the listed services, resources, and operations associated with the service.
The REST API is stateless, which means that REST does not keep track of transactions from one request to the next. Each request must contain all the information necessary for successful processing.
Getting started
To learn more about how the REST API operates, see the examples in Getting started.
Services Directory
Each ArcGIS for Server site comes with a Services Directory. The Services Directory is a view of your available REST resources and operations in HTML format. You can browse the contents of an ArcGIS for Server site and obtain information, such as service metadata and supported operations, that can be useful in developing applications.
Resources and operations
The REST API has some level of support for each of the ArcGIS for Server service types. Each service is a resource and has a unique URL. Although a REST system always returns only representations of resources to the clients, for the sake of simplicity, the resources of the ArcGIS REST API are divided into two types: resources and operations. For more information, see Resources and operations.
The supported service types that include operations are map, geocode, geoprocessing, geometry, feature, network, and image. Another set of service types that is supported as resources but has no associated operations includes mobile, geodata, and globe services.
Output formats
The REST API supports responses in several formats. The format is specified by using the query parameter f in the URL. The list of supported formats includes html (HyperText Markup Language), json (JavaScript Object Notation), image, kmz (compressed KML, or Keyhole Markup Language), help, lyr (layer file), nmf (ArcGIS Explorer map file), amf (Action Message Format), and jsapi (JavaScript). For more details, see Output formats.
KML support
You can request KML in several different ways, which are summarized in KML support.
Versioning
As the REST API evolves, different versions of the API will become available. For information on the rules of versioning, see REST API versioning
REST API administration
In addition to being a browser for your published data, the Services Directory also provides access to an administrative console. The administration page is needed to refresh the site after adding, deleting, and updating services or after updating to a new version of the REST API. The Services Directory can also be disabled through the console. For more information, see REST API admin.