Quick answers to common questions. Click any question to expand the answer, or follow the link to the full article for more detail.Documentation Index
Fetch the complete documentation index at: https://docs.vobiz.ai/llms.txt
Use this file to discover all available pages before exploring further.
Account & Billing
Can I connect my trial number for inbound calls?
Can I connect my trial number for inbound calls?
No. Trial numbers are sandboxed for outbound testing only - no inbound routing until you complete KYC verification and purchase a dedicated DID. To unlock inbound calls, complete KYC in your dashboard (GST for organizations, Aadhaar/PAN for individuals), then purchase a dedicated incoming trunk.Read full article
Can I purchase additional Concurrency or CPS?
Can I purchase additional Concurrency or CPS?
Yes. Log in to the console, go to Account Settings → Limits, and purchase a higher concurrency or CPS ceiling directly through the billing portal. Changes take effect immediately.Read full article
Do you provide 1400, 1600, and 92 series numbers?
Do you provide 1400, 1600, and 92 series numbers?
Yes - 1400, 1600, and 92-series numbers are available. These require additional KYC and carrier approval. Contact support with your use case to initiate provisioning.Read full article
API & Limits
Why am I receiving a 429 error?
Why am I receiving a 429 error?
You’ve hit either your Concurrency limit (too many simultaneous active calls) or your CPS limit (initiating calls too fast). Check your current limits in the console under Account Settings. Fix by throttling your dialer or purchasing a higher limit.Read full article
What is Concurrency?
What is Concurrency?
Concurrency is the maximum number of simultaneous active calls on your account at any moment. If your limit is 10 and 10 calls are live, an 11th attempt returns a 429 or SIP 503 immediately. Calculate your needs based on average call duration × calls per hour.Read full article
What is CPS (Calls Per Second)?
What is CPS (Calls Per Second)?
CPS governs how fast you can initiate calls - independent of concurrency. CPS of 1 means one new call per second. Even with free concurrency slots, blasting 5 calls in the same second with CPS=1 fails 4 of them. Use a pacing queue in your dialer to stay under the limit.Read full article
Why am I receiving SIP response codes 480 or 486?
Why am I receiving SIP response codes 480 or 486?
486 Busy Here - the callee is on another call or rejected the call. 480 Temporarily Unavailable - the device is off, out of range, or in airplane mode. If you see these repeatedly across many numbers on one carrier, that carrier’s spam filter may have blocked your caller ID - pause dialing and contact support.Read full article
Features & Integration
What integrations do you support?
What integrations do you support?
Vapi, Retell AI, LiveKit, ElevenLabs, Pipecat, Bolna, Ultravox, and OpenAI Realtime - all via SIP trunk or WebSocket streaming. Standard SIP interoperability with Asterisk, FreeSWITCH, Teams, and Cisco PBX systems. See the Integrations section for step-by-step guides.Read full article
Is call transfer supported?
Is call transfer supported?
Yes - three methods: (1)
<Dial> XML tag for warm/cold bridge transfers; (2) REST API transfer to redirect a live call to a new XML application mid-call; (3) SIP REFER (RFC 3515) for PBX-native blind or attended transfers.Read full articleDo you support IVR?
Do you support IVR?
Yes. Build IVR flows using
<Gather> for DTMF and speech input, <Speak> for TTS prompts, and <Play> for pre-recorded audio. Your backend returns XML from a webhook - no drag-and-drop constraints.Read full articleTrust & Support
What documents are required for verification?
What documents are required for verification?
Organizations: valid GST certificate (+ authorized signatory in some cases). Individuals: Aadhaar card + PAN card. Documents are encrypted at rest and only used for telecom regulatory compliance - not for any secondary purpose.Read full article
How can I contact support?
How can I contact support?
Open the support chat in the console, or email support@vobiz.ai. For production incidents include your
requestId from the error response to speed up diagnosis.Read full articleBrowse all topics
Trial number inbound
Why trial numbers can’t receive inbound calls and how to unlock them.
Purchase Concurrency / CPS
How to scale up concurrent channels and calls-per-second limits.
1400 / 1600 / 92 numbers
Premium and short-code number provisioning availability.
429 errors
Diagnosing rate-limit and concurrency rejections.
Concurrency
Simultaneous-call limits and how to size them.
CPS
Calls-per-second pacing and queue strategies.
SIP 480 / 486
Distinguishing busy / unavailable / spam-blocked calls.
Integrations
Supported AI agents, SIP providers, and PBX bridges.
Call transfer
Dial XML, REST transfer, and SIP REFER methods.
IVR support
Build branching menus with Gather, Speak, and Play.
Verification documents
KYC requirements for organizations and individuals.
Contact support
How to reach our team and what to include in tickets.
Domestic calling in India
Caller-ID, media anchoring, and KYC requirements.