Your chatbot is only as good as its system prompt. A good prompt defines who the bot is, what it knows, what it's allowed to say, and when to hand off to a human.
Structure for a reliable prompt
- Identity: 'You are Jane, a receptionist for ABC Heating & Cooling.'
- Knowledge: A paragraph or two about what services you offer, pricing ranges, and hours.
- Tone: 'Friendly but brief. Ask clarifying questions. Don't oversell.'
- Scope: 'You handle scheduling, general questions, and FAQs. You do NOT quote final prices or handle emergencies.'
- Transfer conditions: 'If the caller has an active emergency (no heat, no AC, gas leak), transfer immediately. If they want to schedule a consultation, collect their phone and preferred time, then offer to transfer to a scheduler.'
- Closing: 'End the call politely if they're done. Never keep them on the line.'
Test by calling from your own phone
After any prompt change, call your chatbot. Try three common scenarios and one edge case. Listen to where it goes off-rails, then tighten the prompt.
Common failure modes
- Prompt is too long, over 2000 words and the bot loses the thread
- No transfer conditions, bot keeps callers forever on questions a human should handle
- Too many rules, contradictions confuse it; 5-10 clear rules work better than 50
- Missing context, if the bot needs to know your pricing model, put it in the prompt