Virtual (voice-AI) call center
Sources & limits
One company provides the whole voice-AI chain: its native components plus providers billed through it. No bring-your-own components and no mixing of companies. The SIP trunk is the country SIP/PSTN line, except Bland, whose minute includes telephony with Bland numbers (SIP trunk per-minute $0 unless "Own carrier (BYOC)"; DIDs still counted). Prices from voice-ai-source.md; capabilities checked in docs/voice-ai-vendor-interoperability.md, retrieved 2026-09-28.
Retell: STT is included in the Retell voice engine, auto-routed to Azure, Deepgram or Soniox by agent language (docs.retellai.com ASR, 2026-09-28); LLM from the Retell catalogue; TTS = Retell platform voices. (voice-ai-source.md § Retell AI; ../docs/voice-ai-vendor-interoperability.md)
Unverified: LiveKit: LLM catalogue may be stale (2026-09-28: Moonshot no longer listed, Gemma added; rows not updated); PlayHT: status and all prices (play.ht unreachable); Synthflow: STT billing; Synthflow: TTS billing; Vapi: provider catalogue may be stale (2026-09-28 docs list 12 STT / 18 LLM / 18 TTS providers; rows not updated).
Vapi and LiveKit catalogues may be stale: the 2026-09-28 check found more Vapi providers and LiveKit LLM changes; no rows were invented. PlayHT: status unclear (play.ht unreachable, docs still online); not selectable because there is no price data.