Review changes

Author: jaboehri

docs/src/process-development/api-v2/bpmn/execution-listeners.md

@@ -5,4 +5,4 @@ icon: creative
 
 ## Execution Listeners
 
-[Execution Listeners](https://docs.operaton.org/docs/documentation/user-guide/model-api/bpmn-model-api/delegation-code/#execution-listener) can be registered to various flow elements like process, events, tasks, gateways and sequence flows. They are called when the process execution arrives at the flow element they are registered to. 
+Execution Listeners can be registered to various flow elements like process, events, tasks, gateways and sequence flows. They are called when the process execution arrives at the flow element they are registered to. See [Activities]

docs/src/process-development/api-v2/bpmn/messaging.md

@@ -15,13 +15,16 @@ Enabling communication with other lanes, pools or even entirely separate process
 [Message Start Events](https://docs.operaton.org/docs/documentation/reference/bpmn20/events/message-events#message-start-event) allow a BPMN process to be started by an incoming message. In the DSF, all BPMN processes are started via messages. Therefore, it is mandatory to include a [Message Start Event](https://docs.operaton.org/docs/documentation/reference/bpmn20/events/message-events#message-start-event) at the beginning of all DSF BPMN models.
 
 #### Message Intermediate Throwing Event
-[Message Intermediate Throwing Events](https://docs.operaton.org/docs/documentation/reference/bpmn20/events/message-events#message-intermediate-throwing-event) are used to send messages during process execution.
+[Message Intermediate Throwing Events](https://docs.operaton.org/docs/documentation/reference/bpmn20/events/message-events#message-intermediate-throwing-event) are used to send messages during process execution. Message intermediate throwing events that are used to communicate with DSF instances via FHIR Task resources, should implement the DSF API v2 interface `dev.dsf.bpe.v2.activity.MessageIntermediateThrowEvent`.
 
 #### Message Intermediate Catching Event
 [Message Intermediate Catching Events](https://docs.operaton.org/docs/documentation/reference/bpmn20/events/message-events#message-intermediate-catching-event) serve as the counterpart to [Message Intermediate Throwing Events](messaging.md#message-intermediate-throwing-event). They are used to receive a message from another process or organization during execution.
 
 #### Message End Event
-The [Message End Event](https://docs.operaton.org/docs/documentation/reference/bpmn20/events/message-events#message-end-event) will stop the execution of a BPMN process and finish by sending a message.
+The [Message End Event](https://docs.operaton.org/docs/documentation/reference/bpmn20/events/message-events#message-end-event) will stop the execution of a BPMN process and finish by sending a message.Message end events that are used to communicate with DSF instances via FHIR Task resources, should implement the API v2 interface `dev.dsf.bpe.v2.activity.MessageEndEvent`.
 
 #### Message Send Task
-Same as the [Message Intermediate Throwing Event](#message-intermediate-throwing-event), the [Message Send Task](https://docs.operaton.org/docs/documentation/reference/bpmn20/tasks/send-task/) is used to send messages during process execution but is also intended to execute some kind of business logic at the same time.
+Same as the [Message Intermediate Throwing Event](#message-intermediate-throwing-event), the [Message Send Task](https://docs.operaton.org/docs/documentation/reference/bpmn20/tasks/send-task/) is used to send messages during process execution but is also intended to execute some kind of business logic at the same time. Message send tasks that are used to communicate with DSF instances via FHIR Task resources, should implement the API v2 interface `dev.dsf.bpe.v2.activity.MessageSendTask`.
+
+## Related Topics
+[Activities](../dsf/activities.md), [Message Activities](../dsf/message-activities.md)

docs/src/process-development/api-v2/bpmn/service-tasks.md

@@ -5,4 +5,4 @@ icon: creative
 
 ## Service Tasks
 
-One of the most common types of BPMN Tasks used for modeling DSF processes is the [Service Task](https://docs.operaton.org/docs/documentation/reference/bpmn20/tasks/service-task). They are different from regular BPMN Tasks in that they offer the ability to link a Java class to the [Service Task](https://docs.operaton.org/docs/documentation/reference/bpmn20/tasks/service-task) which can be called and executed by a BPMN engine. The BPE (Business Process Engine) server of the DSF leverages this engine to execute BPMN processes and their associated code.
+One of the most common types of BPMN Tasks used for modeling DSF processes is the [Service Task](https://docs.operaton.org/docs/documentation/reference/bpmn20/tasks/service-task). They are different from regular BPMN Tasks in that they offer the ability to link a Java class to the [Service Task](https://docs.operaton.org/docs/documentation/reference/bpmn20/tasks/service-task) which can be called and executed by a BPMN engine. The BPE (Business Process Engine) server of the DSF leverages this engine to execute BPMN processes and their associated code. Java service tasks must implement the API v2 interface `dev.dsf.bpe.v2.activity.ServiceTask`.

docs/src/process-development/api-v2/dsf/activities.md

@@ -5,7 +5,7 @@ icon: creative
 
 ### Activities
 
-Activities are Java interfaces that represent certain BPMN elements which can/need to specify a Java class as their `Implementation` value. Implementing Activity interfaces and [registering them as Spring beans](spring-framework-integration.md) causes the DSF to execute the code provided by the implementation when the process execution reaches the corresponding flow element. The value for the `Implementation` field of BPMN elements expects the fully qualified class name:
+Activities are Java interfaces in the DSF API v2 that represent certain BPMN elements which can/need to specify a Java class as their `Implementation` value. Implementing Activity interfaces and [registering them as Spring beans](spring-framework-integration.md) causes the DSF to execute the code provided by the implementation when the process execution reaches the corresponding flow element. The value for the `Implementation` field of BPMN elements expects the fully qualified class name:
 ```
 org.package.myClass
 ```