How we built 1,000 AI agents that run a marathon

Github repo → https://goo.gle/49tqnbl A thousand AI agents. Each one a real Agent Development Kit (ADK) session. Running a marathon through Las Vegas, all at once. Here's how we built it. In this episode of Hands On AI, Casey West walks us through Race Condition, the multi-agent system he led the development of for the Google Cloud Next 2026 Developer Keynote. It's open source, production grade, and built on Google's Agent Development Kit (ADK). We tear down the architecture, the framework choices, and the patterns that make 1,000 simultaneous AI agents actually work: The 4-layer polyglot stack (Angular · Go · Python · Redis) Two dispatch modes: when HTTP-based A2A fails and Redis pub/sub wins Agent cards & A2A protocol, how agents discover each other Why ADK gives you sessions, callbacks, telemetry, and discovery for free The resilient_model pattern (retries + jitter + exponential backoff) global_gemini, targeting preview models on Agent Runtime Static vs dynamic instructions & context caching Skills: lazy-loaded context + tools for production agents Building a mesh of agents that can call each other Chapters 00:00 - Intro & 1,000-Agent Demo 03:17 - The 4-Layer Architecture 05:23 - System Architecture Diagram 06:59 - Two Dispatch Modes: Subscriber vs Callable 09:54 - Why We Threw Out HTTP for Redis Pub/Sub 13:23 - Agent Cards & the A2A Protocol 16:24 - Why We Built on Google ADK 19:00 - resilient_model: Production-Grade LLM Calls 23:09 - global_gemini: Targeting Preview Models 24:41 - Static Instructions & Context Caching 28:19 - Skills: Lazy-Loaded Tools & Context 34:42 - call_agent & the Mesh Network 39:53 - The Vision: What Else Could Be an Agent? 41:36 - Next Episode Tease More resources: Google Agent Development Kit (ADK) → https://goo.gle/3PItVzL Agent Runtime → https://goo.gle/4nXDhnX Google Cloud Memory Store → https://goo.gle/4nXxBtT Agent2Agent Protocol (A2A) protocol → https://goo.gle/4u5x8HF Casey West on LinkedIn → https://goo.gle/4dXnsJr Annie Wang on LinkedIn → https://goo.gle/43GCXAo Watch more Hands on AI →    • Get hands on with AI   🔔 Subscribe to Google Cloud Tech → https://goo.gle/GoogleCloudTech #AIAgent #MultiAgentSystem #AgenticAI Speakers: Casey West, Annie Wang Products Mentioned: Google Agent Development Kit, Gemini API, Agent Runtime, Google Cloud Pub/Sub, AlloyDB, Agent2Agent Protocol