Learn about External Services' schema limits and other considerations.
Required Editions
| Available in: Lightning Experience |
| Available in: Enterprise, Performance, Unlimited, and Developer Editions |
- System Limits
External Services maximum system limits for registrations, schema size, operations, objects, properties, and file size. - Callouts and Callbacks: Limits and Usage
Limits and best approaches for callbacks and callouts to and from External Services. - Schema Definitions
Learn the basics about External Service's schema support, schema components that are ignored, and supported data types. - Character Set Encodings
Learn about request and response character set encodings. - Media Type Directives and Mapping
Learn about OpenApi 2.0consumes/producesor OpenAPI 3.0contentmedia type schema directives. - Naming and Description Conventions
Learn about support for component names and descriptions defined in your schema. - Defaults and Default Values
Learn about External Services' support for defaults. For OpenAPI 2.0, default values set onpropertiesare used. For OpenAPI 3.0 schemas, the "outermost" default is used. Non-supported configurations are ignored. - Operation Output Parameters
Learn about how External Services interprets an operation's output parameters. - Structure Data Using properties and additionalProperties
In an Open API specification, the properties keyword defines one or more properties on an object including the property name and data type. The additionalProperties keyword gives you the flexibility to add additional properties with an undefined schema. The named properties are accessible as Apex properties with a matching data type. The additionalProperties in the spec are accessible in Apex as a Map property. - Apex Class Names and Developer Names
Learn how External Services derives Apex class names from your schema. - Apex Reserved Keywords
Learn about External Service's support for Apex reserved keywords. - Null Values
Learn null values are interpreted by External Services.