Shared instructions and service tone
Use shared instructions for the rules that remain true throughout this service: who the assistant represents, which language to use, how to address the caller and when it should ask for clarification.
Set the common behavior
Open the assistant's Global element and enter the shared prompt. A conversation has at most one Global element. It is an instruction source rather than a stage the caller passes through, so it does not need connections.
Enable Add Global Prompt on the stages that should receive these instructions. Check the opening and closing as well as the service stages; a disabled toggle means the shared prompt is not included there.
Keep service decisions in their stage
Put questions, action preconditions and transition decisions in the stage where they apply. For example, the requirement to confirm a callback time belongs with the callback request. A general instruction to speak politely belongs in the shared prompt.
After changing shared instructions, test more than one path. A tone change can affect every stage that includes the prompt.