State is not saving after recent update with output_key for agents

[deepakbatham572]

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Contribution guide.

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Please share a minimal code and data to reproduce your problem.
Steps to reproduce the behavior:

1. Install latest version for google adk
2. Run simple adk code with agent state is stored as in output key
3. Open state after executed ,

Expected behavior
State should be saved for all output key

Screenshots

Desktop (please complete the following information):

• OS: [e.g. macOS, Linux, Windows]
• Python version(python -V):
• ADK version(pip show google-adk):

Model Information:

• Are you using LiteLLM: Yes
• Which model is being used openai: gpt-5.1

Additional context
Add any other context about the problem here.

[charlesdassonville]

+1 with:

OS: Apple M1 Pro / 26.0.1 (25A362)
Python: 3.13
ADK: 1.19

[charlesdassonville]

Seems to be corrected with 1.21

[surajksharma07]

@deepakbatham572 This issue was fixed in ADK v1.21.0 (released December 11, 2025).

The fix addresses state not updating in the Web UI, including output_key persistence.
Upgrade with pip install --upgrade google-adk and the issue should be resolved.

If you're still experiencing problems after upgrading to v1.21.0+, please provide a minimal reproduction script and I'll investigate further.