Hey team, I’m building an outbound voice assistant using Vapi and I’ve set up two tools: 1. set_user_requested_pause → works perfectly when the user says things like “hold on” or “give me a sec” 2. handle_dead_air → designed to trigger when the user is silent for 30+ seconds (no pause requested) I’ve written prompt logic that calls handle_dead_air when silence is detected, and I’ve also set the following in my assistant settings: • Idle Timeout: 30 seconds • Max Idle Messages: 2 • System prompt explicitly says to call handle_dead_air during silence But it only works when the user says “give me a sec.” If the user goes completely silent (no speech input at all), the assistant never calls the dead-air tool or says anything — it just waits forever until I say something. I’ve tested this both live and through ngrok/Render, and the dead-air tool is functioning fine if I trigger it manually. Questions: • Is there a way to auto-trigger a tool like handle_dead_air after silence? • Does Idle Timeout support calling tools or just internal messages? • Do I need to use a no_input_timeout config (and if so, how can I access that)? • Is it possible to make the assistant consistently respond after silence without needing the user to speak first?

Hey, it looks like idleMessages usually handle user silence automatically, and you can customize them with the idleMessage object. However, it seems like the handle_dead_air tool you created is overriding the default behavior of idleTimeout, which is causing the assistant to wait indefinitely for a response. By default, idleTimeout is the same as no_input_timeout, so you might not need that tool configured. To have the assistant respond consistently after silence without needing user input, you could revert to the default settings for idleMessages and idleTimeout. This might involve removing the custom tools you built. I know that might not seem ideal, so I recommend duplicating your current assistant's configuration first. Then, try the changes I suggested to see if the default behavior works better for you. Set idleMessages to 3 and idleTimeout to 10 seconds, and you should notice the difference.

Thanks for the detailed explanation — that makes a lot of sense. I hadn’t realized that the handle_dead_air tool was overriding the default idleTimeout behavior, so that’s helpful context. The only reason I’ve been avoiding the default idle behavior is because I can’t customize the messages as flexibly.

Totally understandable. If the default behavior gets in the way of your implementation too much, maybe we can explore some other options but for now please try to stick with it as best as possible. Let us know when you need additional support