# OpenRouter shows how to build a voice AI agent in Python

> Original title: How to Build a Voice AI Agent

- Source: OpenRouter Blog
- Published: 2026-11-10T00:00:00.000Z
- Bad Influence: https://badinfluence.news/items/hcipvqcx7f30713m94tej5zxa
- Original: https://openrouter.ai/blog/tutorials/build-voice-ai-agent/

## Summary

OpenRouter's tutorial builds a restaurant booking voice agent that chains speech-to-text, an LLM with tool calls, and text-to-speech through one API key. In its October 8 tests, the median server-side time to first audio was 1.9 seconds across 12 turns, and text-to-speech made up about 90% of the measured cost. The post also reports speech-to-text and model comparisons, and it recommends confirming names with callers because transcription errors were common.

## Why it matters

The tutorial shows a complete voice agent loop with tool calls, sentence-level streaming to TTS, measured latency, and cost figures that readers can compare against their own builds.