> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.vapi.ai/server-url/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.vapi.ai/_mcp/server.

# Server URLs

> Set up server URLs so your application receives Vapi call events like status updates, transcripts, function calls, and end-of-call reports, and responds.

![](/_fern-img/ffc0a6c6fe5387d5748ac74d6b4453f582db1914301dd265ae5d09dfb06be241.webp)

Server URLs allow your application to **receive data** & **communicate with Vapi** during conversations. Conversation events can include:

* **Status Updates:** updates on the status of a call
* **Transcript Updates**: call transcripts
* **Function Calls:** payloads delivered when your assistant wants certain actions executed
* **Assistant Requests:** in certain circumstances, Vapi may ping your server to get dynamic configuration for an assistant handling a specific call
* **End of Call Report:** call summary data at the end of a call
* **Hang Notifications:** get notified when your assistant fails to reply for a certain amount of time

In our [quickstart guides](/quickstart) we learned how to setup a basic back-and-forth conversation with a Vapi assistant.

To build more complex & custom applications, we're going to need to get real-time conversation data to our backend. **This is where server URLs come in.**

> **Info**
>
> If you're familiar with functional programming, Server URLs are like callback functions. But
> instead of specifying a function to get data back on, we specify a URL to a server (to POST data
> back to).

If you're configuring a Server URL with an AI coding assistant, the [setup-webhook skill](/agent-skills#setup-webhook) helps you connect an endpoint for call events and tool calls.

## Get Started

To get started using server URLs, read our guides:

#### [Setting Server URLs](/server-url/setting-server-urls)

Server URLs can be set in multiple places. Learn where here.

#### [Events](/server-url/events)

Read about the different types of events Vapi can send to your server.

#### [Developing Locally](/server-url/developing-locally)

Learn about receiving server events in your local development environment.

#### [CLI Webhook Testing](/cli/webhook)

Forward webhooks to your local server with the Vapi CLI.

> **Tip**
>
> **Quick local testing with Vapi CLI + tunneling:**
>
> ```bash
> # Terminal 1: Create tunnel
> ngrok http 4242
>
> # Terminal 2: Start webhook forwarder
> vapi listen --forward-to localhost:3000/webhook
> ```
>
> This setup forwards webhook events to your local server. Remember to update your Vapi webhook URLs to use the ngrok public URL.

## FAQ

#### Where can the server be located?

The server URL can be any publicly accessible URL pointing to an HTTP endpoint. This can be a:

* **Cloud Server:** your application might be deployed on a cloud platform like [Railway](https://railway.app), [AWS](https://aws.com), [GCP](https://cloud.google.com/gcp), etc — as a persistent web server.
* **Serverless Function:** services like [Vercel](https://vercel.com/docs/functions), [AWS Lambda](https://aws.amazon.com/lambda/), [Google Cloud Functions](https://cloud.google.com/functions), [Cloudflare](https://developers.cloudflare.com/workers/), etc — allow you to host on-demand cloud functions.
* **Workflow Orchestrator:** platforms like [Pipedream](https://pipedream.com) & [Make](https://www.make.com) allow you to program workflows (often without code) that can receive events via HTTP triggers.

The main idea is that Vapi needs a location on the Internet that it can drop data to & converse with your application.

#### Why not just call them webhooks?

[Webhooks](/glossary#webhook) are traditionally unidirectional & stateless, with the target endpoint usually only replying with a status code to acknowledge message reception. Certain server URL events (like assistant requests) may require a meaningful reply from your server.

"Server URL" is a more general term that encompasses both webhooks & bidirectional communication.

> Learn how to set up your server to receive and respond to messages from Vapi

## Docs

- [Setting server URLs](https://docs.vapi.ai/server-url/setting-server-urls.md): Set Vapi server URLs at multiple levels to handle call events, and learn how priority decides which URL receives a given event.
- [Server events](https://docs.vapi.ai/server-url/events.md): Reference the events Vapi POSTs to your Server URL, with the shared message body shape and the payload fields that vary by server message type.
- [Spam call rejection](https://docs.vapi.ai/server-url/spam-call-rejection.md): Screen inbound Vapi calls with your Server URL, checking the caller number on an assistant-request to reject known spam or return an assistant to proceed.
- [Developing locally](https://docs.vapi.ai/server-url/developing-locally.md): Receive Vapi server events in local development using the Vapi CLI webhook forwarder and a tunneling service to route webhook payloads to your machine.
- [Server authentication](https://docs.vapi.ai/server-url/server-authentication.md): Authenticate Vapi webhooks to your server with custom credentials referenced by credentialId, reusing them across assistants, phone numbers, and tools.