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Welcome to Klen AI

Klen AI is a powerful platform that enables developers to build and integrate AI calling agents into their applications. Our API provides a seamless way to manage calls, agents, contacts, and calendar events, allowing you to create intelligent communication workflows for your business.

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What Can You Do With Klen AI?

  • Automate Phone Conversations: Create AI agents that can make and receive calls, follow scripts, and adapt to conversations in real-time.
  • Manage Contacts: Create, update, and organize your contacts with a comprehensive contact management system.
  • Context Variables: Manage contact and business context variables for personalization
  • Schedule Appointments: Integrate with calendar systems to schedule meetings and appointments.
  • Receive Webhooks: Get real-time notifications about call events, transcripts, and calendar updates.

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Getting Started

To start using the Klen AI API, you’ll need to:

  1. Create an account on the Klen AI platform
  2. Generate an API key from your dashboard
  3. Integrate our API into your application

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API Key Authentication

All requests to the Klen AI API require authentication using an API key. Your API key carries many privileges, so be sure to keep it secure. You can manage your API keys from the API Keys page in your dashboard.

Authentication is performed using the Bearer token method:

curl -X GET 'https://api.klen.ai/api/v1/calls' \
  -H 'Authorization: Bearer klen_YOUR_API_KEY'

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Rate Limits

To ensure the stability of our service, we implement rate limits on API requests:

  • API keys have a requests_per_minute_limit (default: 60 requests per minute)
  • For call initiation, there is a calls_per_day_limit (default: 100 calls per day)
  • For calendar events, there is a calendar_events_per_day_limit (default: 50 events per day)

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Example Use Cases

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Virtual Receptionist

Create a virtual receptionist that answers calls, schedules appointments, and routes calls to the appropriate person.

const klen = new KlenAI('klen_YOUR_API_KEY');

// Create an inbound call agent
const agent = await klen.agents.create({
  name: 'Virtual Receptionist',
  role: 'inbound agent',
  model_name: 'openai-gpt-4.1-nano',
  voice_id: 'alloy',
  instructions: 'You are a friendly receptionist for Acme Corp...'
});

// Assign a phone number to the agent
await klen.phoneNumbers.assign(agent.id, '+15551234567');

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Automated Appointment Reminder

Send automated appointment reminders to customers and allow them to confirm, reschedule, or cancel appointments.

import klen

client = klen.KlenAI('klen_YOUR_API_KEY')

# Get upcoming appointments
events = client.calendar.events.list(
  start_date='today',
  end_date='tomorrow',
  status='confirmed'
)

# Send reminders for each appointment
for event in events.data:
  call = client.calls.create(
    agent_id='123',
    phone_number=event.customer.phone,
    variables={
      'customer_name': event.customer.name,
      'appointment_time': event.start_time,
      'appointment_type': event.title
    }
  )

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Next Steps

  • Quickstart Guide: Get up and running quickly with a simple integration
  • API Reference: Explore the full API documentation
  • Guides: Learn how to build common integrations
  • Examples: See code examples in various programming languages

Need help? Contact our support team.