What characterizes REST APIs in MuleSoft?

REST APIs in MuleSoft are characterized by their specification formats, which include RAML (RESTful API Modeling Language) and OAS (OpenAPI Specification). These formats provide a standardized way to define the structure and behavior of RESTful APIs, enabling developers to describe endpoints, request/response formats, authentication methods, and other relevant details in a human-readable and machine-readable manner.

By utilizing these specifications, MuleSoft facilitates the design, documentation, and management of APIs, allowing for better collaboration between developers and stakeholders. The adoption of RAML or OAS also promotes best practices in API development by ensuring consistent design patterns and encouraging reusability.

The other choices do not accurately represent the characteristics of REST APIs in MuleSoft. For instance, REST APIs do not rely on XML for data formatting specifically, as they support various formats including JSON and others. They also do not depend on SOAP protocols; SOAP is associated with a different style of API, typically more rigid and reliant on XML. Lastly, while metadata can play a significant role in APIs, it is not the defining characteristic of REST APIs, which focus more on the architecture and interaction model rather than solely on metadata use.