adk deploy app-engine with --validate-agent-import parameter fails because .env files are not included.

[slilichenko]

An agent that runs correctly using adk web and relies on some parameters to be provided via .env file fails if that flag is enabled.

Steps to Reproduce:
Please provide a numbered list of steps to reproduce the behavior:

1. Create a settings class which extends BaseSettings and add an attribute which is not initialized
2. Add .env file which provides the value of the attribute
3. Run adk web to confirm that the agent running
4. Run adk deploy --validate-agent-import and see that the validation fails with pydantic_core._pydantic_core.ValidationError.

• ADK Library Version (pip show google-adk): 1.26.0
• Desktop OS: Mac
• Python Version (python -V): 3.14

[surajksharma07]

@slilichenko The validation reads your .env via dotenv_values() into a dict but never injects those values into os.environ, so pydantic BaseSettings can't find them during the import check — as a quick workaround, passing --no-validate-agent-import (or --skip-agent-import-validation) to your deploy command should unblock you immediately.

A proper fix would be to temporarily os.environ.update(env_vars) before the import validation runs in cli_deploy.py, then restore the env afterward.

Could you confirm if the workaround works on your end?

[slilichenko]

I am not looking for a workaround. I use this flag to make sure that I don't have to wait for the Agent Engine to fail and then dig through the Google Cloud Logging to find the reason. It would be great to implement a permanent fix.

[surajksharma07]

@yeesian Please have a look into it once.

[surajksharma07]

@slilichenko That's a fair point — disabling the flag defeats the whole purpose of having early validation.

The fix is well-scoped: _validate_agent_import() in cli_deploy.py needs to temporarily load the .env vars into os.environ before the import, then restore the environment afterward.

I've flagged this to the team for a proper code-level fix.

Team is looking more into it.

Thanks!