Quick start

Let’s build a production-ready voice agent that can respond to users and trigger function calls. Here’s a preview of what you will build:

Real-time speech-to-text, text-to-speech, turn-taking, and low-latency audio delivery powered by Layercode’s edge platform.
A sample agent backend that monitors conversation transcripts and responds based on your prompt and the tool calls you define. Deployable anywhere.

CLI (recommended for Next.js)
Manual setup (Next.js)
Other guides

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npx @layercode/cli init

After the CLI finishes, you will see something like this:

Try it out

Once everything boots, you can start a conversation locally (typically at http://localhost:3000/).

Video walkthrough

Prefer a walkthrough? Watch the quick demo below.

Learn how to create your first voice agent for real-time conversational AI. This guide walks through logging in, creating an agent, and testing it in the playground.

Visit dash.layercode.com and log in or sign up if you haven’t already.
Create a new agent or use the agent that Layercode auto-creates for you.
Copy the agent ID for later.
Click Connect your backend, copy the Webhook secret, and save it for later.
In Account settings, copy your Layercode API key and save it for later.

Choose your stack

Next.js with Cloudflare (recommended)

You will need a Google Gemini API key.

Clone our example repo

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git clone https://github.com/layercodedev/fullstack-nextjs-cloudflare.git
cd fullstack-nextjs-cloudflare

Install dependencies

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npm install

Create an .env file (you can copy .env.example).Populate the variables with the values you grabbed from Layercode in the first step.

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NEXTJS_ENV=development
NEXT_PUBLIC_LAYERCODE_AGENT_ID=
LAYERCODE_API_KEY=
LAYERCODE_WEBHOOK_SECRET=
GOOGLE_GENERATIVE_AI_API_KEY=

Now run your project with npm run dev.

Set up a tunnel

To let Layercode reach your app, expose it to the internet during development.We recommend Cloudflared, Cloudflare’s tunneling utility. Follow our Cloudflare Tunnel guide to install it.Once it is installed, run:

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cloudflared tunnel --url http://localhost:*PORT_NUMBER*

Get your Cloudflared tunnel URL

The logs include a URL similar to https://phone-tom-applying-individually.trycloudflare.com.

Save your URL in the dashboard

Append /api/agent to the URL (for example, https://phone-tom-applying-individually.trycloudflare.com/api/agent).Head to the Layercode dashboard at https://dash.layercode.com/.Open the agent you are working with, click Connect your backend, and paste the URL into Webhook URL. Save your changes.

(yes I did roll the secret)Refresh your app and test it. It should work—and if you get stuck, email us and we’ll help.

It lives

Your agent should now be working—go check it out!

Next steps

Keep iterating—here are the next things builders usually tackle.

Customize your prompts

Adjust the prompt or welcome_message in layercode.config.json.

layercode.config.json

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{
  "layercode_agent_id": "ibcjp4z0",
  "prompt": "You are having a spoken conversation with the user.",
  "welcome_message": "Hey, how can I help you today?"
}

Add a tool call

The project ships with an example tool in /app/api/agent/route.ts. Modify it or add your own.

/app/api/agent/route.ts

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const weather = tool({
  description: 'Get the weather in a location',
  inputSchema: z.object({
    location: z.string().describe('The location to get the weather for')
  }),
  execute: async ({ location }) => {
    stream.data({ isThinking: true });
    // do something to get the weather
    stream.data({ isThinking: false });

    return {
      location,
      temperature: 72 + Math.floor(Math.random() * 21) - 10
    };
  }
});

Learn more about tool calling in Next.js or review the general tool calling guide.

Store your messages

Set up persistent storage for transcripts. A fast database or data store such as Cloudflare D1 or Redis works well. A dedicated guide is coming soon.

Deploy your voice agent backend

Layercode runs the voice pipeline in our cloud, but your backend APIs (and frontend, if you are not using Next.js or telephony) need to be deployed. Use the deployment guides:

Remember to set your environment variables in the hosting platform and update the Layercode dashboard with the deployed webhook URL.

Set up telephony

Follow the Twilio setup guide to add phone-call support.

Use the Layercode tunnel

We provide a tunnel utility for local development.

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# Start a tunnel for agent dtv3x3d2 on port 5173 with the API located at /api/voice-agent
npx @layercode/cli tunnel --agent-id=dtv3x3d2 --port=5173 --path=/api/voice-agent --tail

Overview

SDKs

How-to guides

Explanations

Try it out

Video walkthrough

Choose your stack

Clone our example repo

Install dependencies

Set up a tunnel

Get your Cloudflared tunnel URL

Save your URL in the dashboard

It lives

Backend guides

Frontend guides

Next steps

Customize your prompts

Add a tool call

Store your messages

Deploy your voice agent backend

Set up telephony

Use the Layercode tunnel

Overview

SDKs

How-to guides

Explanations

​Try it out

​Video walkthrough

​Sign up, log in, and grab your keys

​Choose your stack

​Clone our example repo

​Install dependencies

​Set up a tunnel

​Get your Cloudflared tunnel URL

​Save your URL in the dashboard

​It lives

​Backend guides

​Frontend guides

​Next steps

​Customize your prompts

​Add a tool call

​Store your messages

​Deploy your voice agent backend

​Set up telephony

​Use the Layercode tunnel

Try it out

Video walkthrough

Sign up, log in, and grab your keys

Choose your stack

Clone our example repo

Install dependencies

Set up a tunnel

Get your Cloudflared tunnel URL

Save your URL in the dashboard

It lives

Backend guides

Frontend guides

Next steps

Customize your prompts

Add a tool call

Store your messages

Deploy your voice agent backend

Set up telephony

Use the Layercode tunnel