added API descriptions and intents mapping

code/API_definitions/Discovery/README.md

@@ -1,4 +1,21 @@
 # Edge Discovery APIs
+
+## Simple Discovery API
+This API allows a client application to discover the closest MEC platform to the UE hosting the client application. 'Closest' means 'shorteset network path' as that will give the shortest propogation distance, which is a major factor in latency.
+
+## MEC Experience Management and Exposure API
+This API allows a developer to:
+- discover available MEC platforms, ranked by proximity to a UE.
+- read the state (availability and capabilities) of an operator's various MEC platforms.
+- register a service profile (a description of the developer's edge service) with the MEC operator
+- register the deployed service endpoints with the MEC operator, which allows the closest service endpoint to be discovered at runtime
+
+The API will also support the following capabilities: 
+- events(such as change of status of a MEC platform or another event which could affect their service)
+- subscription to notification of events.
+
+# Mapping to the list of intents
+
 These APIs fulfil the ['discovery' intents](https://github.com/camaraproject/EdgeCloud/blob/main/documentation/SupportingDocuments/Harmonisation%20of%20APIs/describing%20and%20harmonising%20the%20Edge%20APIs.md)
 
 *Simple Edge Discovery* fulfils a single intent,  "4. I can discover the closest MEC platform to a specific terminal (closest in terms of shortest network path)"