An AI voice agent is AI-driven voice software that autonomously runs phone conversations. Instead of a recorded message, the agent understands speech in real time, responds in context and follows a defined call script – including objection handling, qualification and meeting booking.
Technically, a modern AI voice agent has three building blocks: speech-to-text (e.g. Deepgram, Whisper), a large language model (e.g. GPT-5, Gemini 2.5) and text-to-speech (e.g. ElevenLabs, Cartesia). A telephony layer (Twilio, Telnyx, SIP trunk) connects the agent to the phone network.
In B2B sales, AI voice agents are mainly used for outbound cold calls, lead qualification (BANT/MEDDIC), meeting booking and reactivation campaigns. The benefits: consistent call quality, full documentation inside HubSpot or Salesforce, and scale far beyond a human SDR team.
Outreach Master integrates AI voice agents directly into HubSpot workflows: a trigger starts the call, transcript + outcome are written back to the contact record, and qualified leads are handed over to a sequence.