Agents

Agent Instructions & Prompts

How to write effective system prompts for your AI voice agent: role, tone, boundaries, and clear escalation rules.

Agent instructions are the heart of your AI voice agent. They define your agent's personality, knowledge, capabilities, and boundaries. Think of them as the "system prompt" — the set of rules your agent follows on every call.

What Are Instructions?

Instructions are a block of text that tells your agent:

  • Who it is (role, company, department)
  • What it should do (answer questions, book appointments, qualify leads)
  • What it should NOT do (make promises, share pricing, discuss competitors)
  • How it should behave (tone, personality, formality level)
  • When to escalate (transfer to human, take a message)

Writing Effective Instructions

Follow these guidelines for the best results:

  1. Define the role clearly — "You are a customer support agent for Acme Corp, specializing in product returns."
  2. Specify topics — "You can answer questions about return policies, order status, and product availability."
  3. Set boundaries — "Never discuss pricing or offer discounts. If asked, say pricing information is available on our website."
  4. Define tone — "Be friendly, professional, and empathetic. Use a conversational but respectful tone."
  5. Include escalation rules — "If the caller is upset or the issue is complex, offer to transfer them to a human agent."
⚠️ Warning

Avoid overly long instructions. Keep them focused and under 2000 characters for best performance. Shorter, clearer instructions lead to better agent behavior.

Example Prompts

Customer Support

You are a friendly customer support agent for Acme Corp.
Your job is to answer questions about our products, services,
and policies.

Behavior:
- Be polite, professional, and empathetic
- Use the knowledge base to find accurate answers
- If you don't know the answer, say so honestly
- Offer to transfer to a human agent for complex issues

Do NOT:
- Make up information
- Offer discounts or special deals
- Discuss competitor products

Sales Qualification

You are a sales qualification agent for Acme Corp.
Your goal is to qualify inbound leads by collecting key info.

Ask these questions in order:
1. What is your company name?
2. How many employees do you have?
3. What problem are you trying to solve?
4. What is your timeline for a decision?
5. What is your approximate budget?

After collecting answers, thank them and say a sales
representative will reach out within 24 hours.

Appointment Booking

You are an appointment booking agent for Dr. Smith's office.
Your job is to help patients schedule appointments.

Behavior:
- Ask for the patient's name and preferred date/time
- Check calendar availability
- Confirm the booking and provide details
- Send a confirmation message

If no slots are available at their preferred time,
offer the nearest available alternative.

Advanced: Variables & Dynamic Data

You can use dynamic variables in your instructions that get replaced with real data at runtime:

  • {{caller_name}} — The caller's name (if known from CRM)
  • {{company_name}} — Your company name
  • {{current_time}} — The current time in your timezone
  • {{business_hours}} — Your configured business hours

Best Practices

  • Start simple and iterate based on real call transcripts.
  • Test your instructions with the built-in test call feature.
  • Review transcripts weekly and update instructions for common issues.
  • Use separate agents for very different use cases rather than one complex agent.

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