Voice AI Premium

Using Twilio with Retell AI via SIP Trunking for Voice AI Agents

Note: This article is in conjunction with the following articles:  1. Understanding PBX for Voice AI,  2. Overflow and After-

Guide and best practices for purchasing phone numbers for Voice AI.

Note: This article is in conjunction with the following articles: Understanding PBX for Voice AI, Overflow and After-Hours Voice

Understanding Call Forwarding to Voice AI Agent

This article is in conjunction with the articles: 'Understanding PBX for Voice AI' and 'Overflow and After-

Understanding PBX for Voice AI

Understanding PBX is crucial because it’s the “traffic controller” for business calls. It decides how calls flow, who they

Building post-call data extraction variables in Retell AI

This article explains how to build reliable post-call data extraction for voice AI agents.  By the end, you'

Building a Retell AI Multilingual Voice Agent

A multilingual voice agent can understand and reply in more than one language during a single call.  The multilingual voice

Understanding Environment Tags in Retell AI

What are Environment Tags in Retell AI? An environment tag is a named pointer that you attach to a version

Understanding Versioning in Retell AI

Versioning lets you update a voice agent while keeping other versions unchanged. This means you can keep improving an agent

Fix something you don't understand = add complexity you understand even less

Many AI content developers will tell you that you don't really need to know n8n anymore. Just use

Your automation workflows are guaranteed to fail under production load without this.

The biggest mistake companies make in AI workflow development is trying to automate 100% of their processes, and that too

Overflow and After-Hours Voice AI Receptionist

For Voice AI solutions, a well-established business with high call volume is an ideal client. But one big problem

Reducing Voice Agent Latency by Testing Different TTS Engines

If, for whatever reason, you can not reduce the token size of your voice agent prompt but still want to

Zero-Width Characters in Voice Agent Prompts

Check your voice agent prompt for zero width character immediately after creating the first draft of the prompt. What are

What over 1000 Hours of AI Training Taught Me

I’ve been tracking my time for over a decade using a time-tracking tool called 'Hravest'. So

Four LLM Failure Modes and One User Failure Mode

As I crossed over 1000 hours working with AI, I discovered 4 LLM failure modes and 1 user failure mode.

Run both Voice AI agent and test simulator on the same model

Your Voice AI Agent uses a specific LLM model: Make sure your test simulator (feature used for simulation testing) uses

Most AI Projects Fail. But Yours Will Succeed.

Most AI projects fail esp at the enterprise level. “95% of enterprise AI and GenAI pilots fail to achieve measurable

Voice Agent Prompt Formatting Matters Lot More Then You Think

When your Voice AI grader is wrong, not your agent

Every dynamic variable in voice agent needs a fallback.

Retell AI Current Time Awareness has a reliability problem.

Retell AI ships a feature called Current Time Awareness.  You set a timezone, and the platform is meant to inject

The 80/20 Rule of Voice Agent Development

I have been testing a voice agent for the last 3 weeks. That seems like a lot of testing. Yes,

Understanding Retell AI Transfer Screening Agents.

Open the Retell AI dashboard, and you will find a tab labelled "Transfer Screening Agents."  Click on the

Abuse Ladder in Voice AI - Stop hostile calls from spiralling

What is the Abuse Ladder in Voice AI? The abuse ladder is a short, structured response script for when a

When to split your voice agent - The Bleed Test Framework.

I built Mark, a voice receptionist for an HVAC company. He runs on Retell, the platform we use to host

Why your Voice prompt needs a clean-up pass

The required-field loop that breaks voice agents.

The Realistic Latency Target for Voice Agents.

Gemini 3.1 Flash-Lite Works Well for Voice AI.

Gemini 3.1 Flash-Lite is one of the best models for production voice AI right now. It is fast,

Call your Voice AI Agent a "receptionist," not an "assistant."