VAPI

Vapi helps developers build, test, and deploy voice agents at scale. We enable everything in between the raw models and production, including telephony, test suites, and real-time analytics.

Join

VAPI

Vapi helps developers build, test, and deploy voice agents at scale. We enable everything in between the raw models and production, including telephony, test suites, and real-time analytics.

Join

support

faq

like-gold

8/20/2025

Vapi Client using C#

I'm trying to implement a Vapi client using the c# nuget package for .net. I am able to connect our application to the service, however I can't figure out how to start a call. Vapi seems to provide a .start() method to other platforms, but I can't find the equivalent for the .net environment.

eager-peach

8/20/2025

Does VAPI support: Swiss German language?

Based on available documentation and examples: Vapi.ai does not explicitly list Swiss German (gsw) among supported languages. That said, unsupported or obscurer dialects may still function if integrated via the platform’s transcription and TTS providers, but likely without dialect-specific accuracy or native-sounding voices....

conscious-sapphire

8/20/2025

Call Forwarding dropping calls

Hello support, We have raised this previously and it has not been resolved. I will therefore recap the issue below as we have tried many different things including some tips from you but the issue is still persistent. The flow of the call: My mobile phone to a Vonage number - that triggers the assistant. Assistant triggers callforward. The transfer was to another Vonage number/assistant/mobile phone. The agent is using custom tranferCall tool. The conversation goes fine and the assistant tried to forward the call with the error: call.in-progress.error-transfer-failed. We are using Vonage for our assigned numbers (both for the number being called in and for some of the forwarding numbers)...

broad-brown

8/20/2025

Using variables in Prompt and Tools

very fustrating in my prompt i'm trying to capture and store customer name as a variable Begin the conversation and get the the customers name. store this as {{customer.name}}...

helpful-purple

8/20/2025

Urgent: Voice Cutoff & Incorrect Responses Issue – Immediate Attention Required (Call ID: 5b31bc05-a

Dear Vapi Team, We urgently need your assistance regarding a critical issue experienced during a client demo. During the session, the agent’s voice unexpectedly cut off mid-sentence multiple times and did not complete responses. This left the conversation incomplete and highly unprofessional. Additionally, upon reviewing the transcripts, it is clear that the assistant’s responses were not correct or relevant. The agent failed to answer appropriately throughout the call, which worsened the situation....

extended-salmon

8/20/2025

GHL

I have connected Vapi with my GHL account, but the details are not fetched in the GHL account. Can you please check the connection? Is there anything I've missed, or something else?...

ambitious-aqua

8/20/2025

BYO SIP 480 error

Call ID: eae8f7a6-6df3-4b87-bc61-44381e007d00 Another one b582c2e0-06a2-4af3-8b64-cb908b32f4e0...

ratty-blush

8/20/2025

Urgent Project

I have got an urgent AI project for you. Plz DM me.

equal-jade

8/20/2025

How do I add GPT-5-Mini in the API?

I'm using the API to build agents, and I want them to be configured with GPT-5-Mini. How can I do this?

generous-apricot

8/20/2025

Unable to add credits

Card keeps declining. Org ID: 4f6ee843-e71f-4eee-8238-9d58168e6f05...

national-gold

8/20/2025

Dynamic variables outside of system prompt

I have an assistant that is using dynamic variables in the system prompt and first message successfully, i.e., {{ customerName }}. Is it possible to use these variables in other places as well, such as in structured data descriptions or summary prompts, etc?

passive-yellow

8/20/2025

Clarification on Prompt Tokens Estimate for Voice Agent

Hi Vapi Team, I’m working on estimating the pricing for a voice agent and would appreciate some clarification on how the calculator works. Use Case:...

quickest-silver

8/20/2025

Embedded VAPI agent does not show icons in WordPress website

Hi there, When I embed my VAPI AI agent into a WordPress website using the HTML code provided, the icons meant to show the following appear as solid-coloured squares and rectangles instead (see attached screenshots) - Reset conversation...

magic-amber

8/20/2025

assistant-forwarded-call

When I arranged assistant forwarding call to a SIP URI it was forwarded. But never arrived to my SIP server. No even hits in logs of the SIP credentials. Can you suggest what should I take a look in to?

compatible-crimson

8/20/2025

How to enable this through Create Assistant API - ENABLE END CALL FUNCTION

constant-blue

8/20/2025

Custom LLM getting partial messages, with significantly delayed full messages

Hey all. We're having an issue with our chat/completions API (custom LLM). We've been relying on the messages sent as part of the chat/completions payload instead of managing state ourselves, because it seems that the messages get rewritten. We're getting an issue when the user's response is very short, like a one-word "yes". When the response is very short, it seems that the assistant response in the message payload is somehow cut off. For example, we'll get a call with:...

correct-apricot

8/20/2025

Customer Number isn’t correct

We’re running into an issue where the customer’s real phone number isn’t coming through. Since we route calls with 3CX, the same number is showing every time instead of the actual number the customer is calling from. This means we can’t identify the customer correctly. Is it possible for the caller ID to be passed through so we always get the customer’s real number?...

conscious-sapphire

8/20/2025

Cannot connect Telnyx number to Vapi.

How is correct way to connect Telnyx nuber to Vapi? Docs seems to be outdated from actual screens. I managed to make connection with other account about half a year ago, but cannot make it now, Vapi doest recognize Telnyx API.

extended-salmon

8/20/2025

customer number

I'm trying to send the customer.number variable through to a google scripts api with a tool, but vapi isn't populating it like my other extracted variables when i do a full trial call, it just sends through the default value "unknown" any ideas how i should reference it

ratty-blush

8/20/2025

Easy

I’m looking for someone interested in earning a reasonable amount of pay for simple, non-technical work. You have a PC and it is OK if you don't know about the code. It’s an easy opportunity with minimal effort — great deal for anyone looking to make a bit of extra cash! DM me if you’re interested. I have rich experience for developing web project. DM me if u r interested....

Previous Next