How to write a clearer AI voice agent prompt

1. Give the agent one primary goal

Start with a single outcome such as qualifying an enquiry or confirming a delivery preference. If the prompt contains several competing goals, state their order explicitly.

2. List the information it must collect

Name the required fields and explain why they matter. Tell the agent what to do when the caller does not know an answer or does not want to provide it.

Goal: Qualify the caller's product enquiry.
Collect: preferred product, timeline, and callback availability.
Boundaries: do not invent pricing or product availability.
Ending: summarize the next step and close politely.

3. Define boundaries and a clean ending

State what the agent must not claim. Include a short instruction for summarizing the agreed next step and ending the conversation when the caller is finished.

4. Improve it from session evidence

Review completed and failed sessions separately. Use the transcript or recording when available, change one instruction at a time, and compare the next set of calls before making another change.