improve asyncapi document definition

pages/docs/concepts/asyncapi-document/index.md

@@ -3,7 +3,7 @@ title: 'Introduction'
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-The AsyncAPI Specification defines a set of files (AsyncAPI documents) required to describe the API of an application. The AsyncAPI document describes the message-driven API in accordance with the AsyncAPI Specification via JSON objects that conform to the JSON standards. YAML, being a superset of JSON, can also be used. It also offers a standardized approach for documenting and describing asynchronous and event-driven systems, clearly defining various objects such as channels and messages. Additionally, users can leverage both the AsyncAPI document and tools like the AsyncAPI Generator for code and documentation generation, enhancing efficiency and consistency in their development processes.
+The AsyncAPI Specification defines a set of fields that can be used in an AsyncAPI document to describe an application's API. The document may reference other files for additional details or shared fields, but it is typically a single, primary document that encapsulates the API description.
 
 Furthermore, the AsyncAPI document acts as a communication contract between `receivers` and `senders` within an event-driven system. It specifies the payload content required when a service sends a message and offers clear guidance to the receiver regarding the message's properties.