Customer Join Timeout

Configure web call join timeout for better success rates

Overview

Customer Join Timeout sets the maximum time users have to join a web call before it’s automatically terminated. This parameter helps you optimize call success rates by accounting for real-world connection challenges.

You’ll learn to:

Configure timeout values for different user scenarios
Monitor join success rates and failures
Troubleshoot timeout-related call issues

This setting applies only to web calls. Phone calls are not affected by this parameter.

How it works

When a web call starts, users must complete several steps within the timeout window:

Network Connection

Establish connection to Vapi servers

Permissions

Grant browser microphone access

WebRTC Setup

Complete audio handshake process

Default timeout: 15 seconds
Available range: 1-60 seconds

If users don’t complete all steps within the timeout, the call ends with an assistant-did-not-receive-customer-audio error.

Configuration

Configure customerJoinTimeoutSeconds through the Vapi API for both permanent and transient assistants.

Create Assistant

Update Existing

Transient Assistant

Assistant Overrides

Set timeout when creating a new assistant:

1 import { VapiClient } from "@vapi-ai/server-sdk";
2 
3 const client = new VapiClient({ token: process.env.VAPI_API_KEY });
4 
5 const assistant = await client.assistants.create({
6   name: "Customer Support Assistant",
7   model: {
8     provider: "openai",
9     model: "gpt-4.1-mini"
10   },
11   voice: {
12     provider: "11labs",
13     voiceId: "21m00Tcm4TlvDq8ikWAM"
14   },
15   customerJoinTimeoutSeconds: 30
16 });

Optimization guidelines

Recommended timeout values

Choose timeout values based on your user scenarios:

User Type	Recommended Timeout	Reason
Corporate users	45-60 seconds	Security policies, proxy delays
Mobile users	30-45 seconds	Permission prompts, slower networks
International users	30-60 seconds	Higher latency connections
First-time users	45-60 seconds	Unfamiliar with interface
Returning users	20-30 seconds	Familiar with flow

Balancing considerations

Higher Timeouts

Benefits: - Improved join success rates - Better user experience - Fewer support requests Trade-offs: - Resources tied up longer - Delayed error detection

Lower Timeouts

Benefits: - Faster resource cleanup - Quick failure detection - Reduced server load Trade-offs: - More failed joins - Frustrated users

Monitoring and troubleshooting

Key metrics to track

Monitor these call ended reasons to optimize your timeout settings:

assistant-did-not-receive-customer-audio

Meaning: Customer didn’t complete join process within timeout

Actions:

Increase customerJoinTimeoutSeconds value
Analyze user feedback for connection issues
Consider user base demographics

customer-did-not-give-microphone-permission

Meaning: Legacy reason replaced by above (for better clarity)

Actions:

Review your browser permission prompts
Add user guidance for microphone access
Consider increasing timeout for permission flow

Example scenario analysis

A user attempting to join needs:

5 seconds: Network connection establishment
10 seconds: Microphone permission prompt and user response
8 seconds: WebRTC handshake completion
Total: 23 seconds required

With 15-second timeout: Call fails
With 30+ second timeout: Call succeeds

Start with 30-60 seconds and adjust based on your success rate analytics.

Meeting has ended message

This message appears when a call ends naturally and is informational only—not an error.

Best practices

Start conservatively

Begin with 30-60 second timeouts to establish baseline success rates.

Monitor analytics

Track join success rates and timeout-related call ended reasons in your dashboard.

Test thoroughly

Validate timeout settings in staging environment before production deployment.

Segment users

Consider different timeout values for different user types or regions.

Provide user feedback

Show loading indicators and connection status during the join process.

Next steps

Now that you understand customer join timeouts:

Monitor your metrics: Check your call analytics for timeout-related failures
Explore call features: Learn about real-time call control
Understand call failures: Review call ended reasons for comprehensive troubleshooting

1	import { VapiClient } from "@vapi-ai/server-sdk";
2
3	const client = new VapiClient({ token: process.env.VAPI_API_KEY });
4
5	const assistant = await client.assistants.create({
6	name: "Customer Support Assistant",
7	model: {
8	provider: "openai",
9	model: "gpt-4.1-mini"
10	},
11	voice: {
12	provider: "11labs",
13	voiceId: "21m00Tcm4TlvDq8ikWAM"
14	},
15	customerJoinTimeoutSeconds: 30
16	});