Retell AI

Retell AI is a comprehensive, no-code platform for building, testing, deploying, and monitoring AI-powered voice agents that can handle phone calls naturally. The platform enables businesses to create conversational AI agents that can answer questions, schedule appointments, resolve administrative issues, and collect customer feedback—all without requiring extensive coding.

Retell AI uses advanced language models (like GPT-4o and GPT-4.1) to power voice agents that can engage in natural, human-like conversations. The platform supports both inbound and outbound calls, integrates with various telephony providers like Twilio, and offers real-time conversational performance with sub-second latency across speech recognition, reasoning, and voice synthesis.

Retell AI agents can perform a wide range of tasks including customer support, where they answer FAQs, reset passwords, verify transactions, and address account questions. They also handle appointment scheduling by automatically scheduling and confirming appointments. Furthermore, they engage prospects and qualify leads through lead qualification and follow-ups. For feedback collection, agents can embed NPS and CSAT questions directly within live calls, achieving 5-7 times higher completion rates than traditional surveys. Voicemail detection allows them to detect voicemail and leave pre-recorded or dynamically generated messages. Finally, they facilitate warm transfers by handing conversations to human agents with full context preserved.

No. Retell AI is designed as a no-code platform with an intuitive UI that allows non-programmers to build and deploy voice agents. You can define behavior through a simple interface by writing high-level goals and selecting conditions or actions without writing extensive code.

Retell AI's knowledge base allows agents to automatically access and reference business information to provide accurate answers. The knowledge base can be populated through multiple input methods and automatically syncs with webpages, documents, and custom content, ensuring customers always receive up-to-date information without manual retraining. You don't need to change your agent's prompt to use the knowledge base—it integrates seamlessly.

You can create your first phone agent in approximately 5 minutes. The basic setup involves creating a new agent in the Retell dashboard, configuring basic parameters such as voice selection, response speed, and integration endpoints, connecting your knowledge base or FAQ system, and setting up custom actions and integration points as needed.

Retell AI offers extensive integration capabilities including telephony providers like Twilio and other providers for making and receiving calls, seamless integration with CRM systems, scheduling tools such as calendar and appointment systems, support for custom APIs including GET, POST, PUT, PATCH, and DELETE requests, webhooks for custom workflows and data handling, and the Model Context Protocol (MCP) for advanced integrations with external databases.

Yes. Retell AI agents can make and receive phone calls, handling concurrent outbound calls for use cases like appointment confirmations, lead follow-ups, customer surveys, and voicemail detection.

Retell AI's agents are fine-tuned on millions of real customer conversations and can handle interruptions, nuanced language, and maintain context across multiple conversation turns. The platform uses advanced models like GPT-4o that enable dynamic conversation flows without requiring extensive prompt engineering or hardcoded logic.

Yes. Retell AI includes an enterprise dashboard that provides insights on call success rates, latency, sentiment analysis, and customer satisfaction metrics, enabling teams to optimize continuously.

Retell AI welcomes feedback, feature requests, and help inquiries through their support channels and community forums to help you succeed with the platform.