Does anyone know how to create inbounnd webhoooks & extract variables from them in a single prompt? I can't find it in docs I found a section in docs which might mention about this but its showing error 404 can anyone please help?

Set a server.url in the assistant or phone config, handle incoming POST events on your server, and extract variables like call_id or variableValues, you can also pre-fill variables in prompts using assistantOverrides.variableValues when initiating the call.. https://docs.vapi.ai/server-url/server-authentication https://docs.vapi.ai/server-url

I have did all those things and in my first message I wrote also variable name like this {{first_message}} and in the POST req i am sending the exact json as asked by Vapi and from n8n also I am getting the response and from Vapi side also post req is coming but when I type {{first_message}} or any other variable name so that it can read the answer but instead of that its reading first name..

The {{first_message}} only work if set via assistantOverrides.variableValues at call start; setting them later via webhooks like from n8n during assistant-request won’t update prompts, which is why it defaults..

so where to put webhooks and should I add a filter in n8n to take call_start but the address should be put inside server url right under messaging?

Set your n8n Webhook URL in Vapi’s Server URL field, then filter for call-started events in n8n and trigger a POST /call/phone with variable overrides to properly start the call with dynamic prompts.