Build a real-time voice AI agent with Google ADK and Gemini Live API

Code for this episode → https://g.dev/cloud/voicedemo1
Gemini Live API docs → https://g.dev/cloud/gemini-live
Agent Development Kit (ADK) docs → https://g.dev/cloud/adk-docs

In this video, we built a real-time voice agent you can talk over with Google ADK. Not a speech-to-text pipeline — one open connection, audio streaming both directions at the same time.

Three parts:
* The architecture (browser, WebSocket, backend, Gemini Live, and why live voice is a phone call and not a walkie-talkie)
* The ADK building blocks (describe an Agent, hand it to a Runner, keep the Session in memory)
* The live loop, where the LiveRequestQueue decouples the two audio directions so neither one blocks the other.

Plus the two things people get wrong: send_realtime() for continuous streams vs send_content() for complete input, and why you keep sending audio even when nobody's talking.


Chapters:
0:00 - The agent we're building
0:25 - What you'll learn (three parts)
0:55 - Why the STT → LLM → TTS pipeline feels broken
1:23 - A phone call, not a walkie-talkie
1:49 - The architecture: browser, WebSocket, backend, Gemini Live
2:19 - The ADK Agent: model, personality, tools
3:00 - The Runner: who actually runs the live call
3:13 - The Session: why live voice keeps it in memory
4:10 - The problem: two audio streams, neither can block
4:34 - LiveRequestQueue: the sushi belt
5:01 - send_realtime: streaming mic audio
5:33 - Always send — even the silence
6:01 - send_content: discrete input, and the rule of thumb
6:30 - run_live: audio, captions, tool calls, interrupted
7:02 - Trace one sentence, end to end
7:55 - The in-memory session gotcha
8:20 - Recap: architecture, building blocks, live loop
8:54 - Next episode: giving the agent tools


More resources:
Roadmap preview → https://g.dev/cloud/mma-roadmap
Last episode: the raw Gemini Live API. Next episode: real tools, so she acts instead of just talking. → https://youtu.be/pFc-HcUgFgY?si=wzcKjGAH-s5lltTL

Follow Annie online:
LinkedIn → https://goo.gle/annie-linkedin
X → https://goo.gle/annie-x

Watch more The Omni App → https://g.dev/cloud/modern-ai-app
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#GeminiLiveAPI #VoiceAI #AIAgents #MULTIMODAL

Speaker: Annie Wang
Products Mentioned: Gemini Live API, Agent Development Kit