How to Run Gemini 3 on Agent Engine with ADK

If you're trying to deploy an ADK agent with Gemini 3 to Agent Engine and getting a 404 error, here's the fix. TL;DR Two ways to make it work: 1. adk deploy agent_engine command Pass a .env file containing GOOGLE_CLOUD_LOCATION=global via the --env_file flag. uv run adk deploy agent_engine \ --project = $PROJECT_ID \ --region = $LOCATION_ID \ --env_file = $ENV_FILE \ --display_name = "Greeting Agent" \ sample_agent 2. Python script Add the following to the agent_engines.create parameters: remote_agent = agent_engines . create ( agent_engine = root_agent , display_name = " Greeting Agent " , requirements = [...], env_vars = { " GOOGLE_CLOUD_LOCATION " : " global " , # ← set the global region }, ) Sample code Koichi73 / adk-gemini-3-in-agent-engine How to run ADK agents, including Gemini 3, on Agent Engine. Run Gemini 3 Series on ADK + Agent Engine A sample project for deploying ADK agents with Gemini 3 series models (e.g., gemini-3-flash-preview ) to Agent Engine. To use Gemini 3 series