In call

d2072b71-cd96-4d79-969d-d84c6e4c8b69

I called a Google Voice number. Calls to Google Voice start with something like "Please tell us your name and we will connect you" or something similar. I would expect Vapi to handle this but instead it flags the call as voicemail and ends the call.

Makes perfect sense. Basically, most telephony engines (and Vapi's use of Jambonz is no different) includes an answering machine detection tool. That detection tool is based in most cases on an energy level heuristic, which means: "the call was answered and there was voice measured immediately, the voice ended after X amount of seconds, and there is no more audio measured" - this algorithm will trigger a voicemail detection even for a simple office IVR. You can simulate yourself, have VAPI call you, answer the call with a silly message then mute the microphone, the result should be identical. Doing a speech transcription based voicemail detection will be way too expensive to work with, thus, this is how the mechanism works.

I see. That makes sense but it’s slightly annoying since a decent chunk of the people we’re calling have google voice. Is there any way to turn off voicemail detection and just let the transcriber -> model -> stt handle that initial messaging?

There should be a way to do it i guess. But you'll need to dig the api for thatm

Configure the assistant to use Google's voicemail detection provider, which is likely to better handle Google Voice's specific patterns and greetings. \## Detailed Solution There's a Google-specific voicemail detection provider available that might be better suited for detecting actual voicemails on Google Voice while ignoring the initial greeting message. When you update your assistant via the API (using PATCH /assistants/{assistant_id}), include this configuration: \`\`\`json { "voicemailDetection": { "provider": "google", "voicemailExpectedDurationSeconds": 25 } } \`\`\` The

voicemailExpectedDurationSeconds

parameter (which defaults to 25 seconds) controls how long the Google detector listens to determine if it's a voicemail. You can adjust this value between 5-60 seconds depending on your needs. However, as with many speech services, it's likely optimized for English first, with varying levels of support for other languages. If you find that the Google provider still doesn't properly handle certain languages, you might want to: 1\. Test with different

voicemailExpectedDurationSeconds

values 2\. Consider using the VoicemailTool approach. Using Google's voicemail detection for Google Voice numbers creates better alignment between the service being called and the detection method. Google's own voicemail detection is more likely to correctly distinguish between Google Voice's initial greeting and an actual voicemail message, resulting in fewer false detections and fewer dropped calls.

makes sense, thank you

Marking this ticket as Solved ✅