Vapi

Vapi is a voice AI platform for building conversational agents. Preclinical connects to Vapi via their Chat API to test your assistants with text-based conversations.

Configuration

Field	Required	Description
api_key	Yes	Vapi API key
assistant_id	Yes	Target assistant ID
api_base	No	Override API base URL (default: https://api.vapi.ai)

Alternative field names: provider_id or providerId can be used instead of assistant_id. All fields also accept camelCase (apiKey, assistantId).

Setup

1. Go to Vapi Dashboard > Settings > API Keys and copy your API key
2. Go to Assistants, select your assistant, and copy the Assistant ID
3. In Preclinical, create a new agent:

{
  "name": "My Vapi Assistant",
  "provider": "vapi",
  "config": {
    "api_key": "your-vapi-api-key",
    "assistant_id": "asst_xxxxx"
  }
}

How It Works

Preclinical -----> Vapi Chat API -----> Your Assistant
(Pen Tester) <-----              <-----

1. Preclinical sends a message via Vapi's Chat API (POST https://api.vapi.ai/chat)
2. Your assistant processes the message and responds
3. Process repeats for configured number of turns (conversation continuity via chatId)
4. Final transcript is graded

Common Errors

Error	Cause	Resolution
401 Unauthorized	Invalid API key	Check api_key in config
404 Not Found	Invalid assistant ID	Verify assistant_id exists
429 Rate Limit	Too many requests	Automatic retry with backoff
500 Server Error	Vapi internal error	Automatic retry

Troubleshooting

Empty responses -- Verify assistant responds to messages. Check assistant's prompt configuration. Test assistant manually in Vapi playground.

Authentication errors -- Verify API key is correct and active. Check key has required permissions.