The process debugger supports multiple receive steps and multiple input documents. When a receive step is configured to start a process, the process debugger presents the input document at the start of the debug session. A receive step that can start a process might be a Message Start Event, a Signal Start Event, or a Receive Task.

When a receive step is not configured to start a process, it must join the process instead. A receive step that cannot start a process might be an Message Intermediate Event, Signal Intermediate Event, or a Receive Task. The process debugger does not present joining documents at the start of the debug session.

In order for a process to receive a joining document during debugging, you must publish the document manually. If the receive step receiving the document is not inside of a BPMN subprocess, you can publish the document at any time after the debug session starts. If the receive step is inside a BPMN Subprocess, you must publish the document after the subprocess starts in order for it to be received. The receive step must be active when the document arrives.

The process debugger does not stop on an intermediate start step (a receive step, for example) unless you set a breakpoint on it. If a process thread starts from an intermediate start step, the debugger runs through the thread to its completion by default if no breakpoint is set on the start step.