Prerequisites
- A Plivo phone number configured in Settings → Phone Number
- LLM API credentials (OpenAI, Anthropic, or Google) — you’ll add these during configuration
Step 1 — Create a new agent
- In the sidebar, navigate to Voice Agents.
- Click New Agent.
- Enter a Name for the agent (e.g., “Support Agent”, “Sales Qualifier”). This is internal-only and not spoken to callers.
Step 2 — Write the system prompt
The system prompt is the most important part of your agent. It defines:
- Who the agent is — name, role, and tone
- What it can help with — scope of topics it should handle
- What it should not do — topics to avoid or redirect
- How it should behave — conversation style, how to handle uncertainty
Example system prompt:
You are Alex, a friendly customer support agent for Acme Corp.
Your job is to:
- Answer questions about our products and shipping policies
- Collect the caller's order number and look up their order status
- Schedule a callback if you cannot resolve the issue
Keep your responses concise — this is a phone call, so avoid long monologues.
If the caller asks about billing disputes, let them know this is handled by a specialist and offer to take a message.
Always end the call politely. Do not discuss competitor products.
Phone conversations have different constraints than text. Keep agent responses short (1–3 sentences). Avoid bullet points and lists — they don’t translate well to speech.
Step 3 — Set firstSpeaker
firstSpeaker controls who speaks first when a call connects:
| Option | Behaviour | Best for |
|---|
agent | Agent immediately greets the caller | Inbound support lines where you want a consistent greeting |
user | Agent waits for the caller to speak first | Outbound calls where the agent dials the contact |
Step 4 — Assign a phone number
Select the Plivo phone number that will route incoming calls to this agent. Each phone number can be assigned to one agent at a time.
If no phone numbers appear in the dropdown, go to Settings → Phone Number to configure one first.
After creating the agent, open the Configuration tab to set up:
- LLM — the AI model that reasons and generates responses
- Transcriber — the speech-to-text engine that converts caller audio to text
- Voice — the text-to-speech voice used to speak replies
See Configure LLM & Voice for details.
Step 6 — Save and go live
Click Save. The agent is immediately active — any call to the assigned phone number will be handled by this agent.
To pause the agent without deleting it, unassign the phone number or remove the number from Settings → Phone Number.
Testing the agent
The easiest way to test is to call your Plivo number from a mobile phone. You can also use Plivo’s call simulation tools in their dashboard.
After a test call, go to Voice Agents → Call Logs to see the call record and open the full transcript to review the conversation.
