Developer guides

Learn to build voice agents.

How to build with our speech and agent APIs: Hindi text to speech, speech to text, the Realtime API, phone calls from code and bulk campaigns.

  • 21guides in 5 topics, from a first call to the GPUs
  • 71references cited and linked

Voice infrastructure

These notes measure the stack under a voice agent.

The infrastructure notes on Gemma, FP4, vLLM and context management are here too, with their data.

Agent design

Design an agent that keeps the call on track.

Prompts, flows and the tests that tell you a rewrite helped.

Start building

Start here to place your first call from code.

Keys, a first call, a webhook and a campaign, with the requests written out.

Speech APIs

Turn text into speech, and speech into text.

Hindi text to speech, speech to text and the Realtime API, with prices compared.

Production engineering

Keep your calls healthy once they are live.

Webhooks you can trust, and latency you can measure.

  1. AI agents from ₹1 a minute: on our volume plan, ₹1,00,000 a month. Pay as you go is ₹5 a minute. Prices exclude GST.