BUG: ADK fails for the next user query just after the even compaction event has been generated

[MahorShekhar]

Facing issues in getting response from ADK for the user input just after even compaction event has been generated.

  File "/Users/Shekhar/cosmos-adk-v3/venv/lib/python3.13/site-packages/google/adk/flows/llm_flows/base_llm_flow.py", line 375, in _run_one_step_async
    async for event in agen:
      yield event
  File "/Users/Shekhar/cosmos-adk-v3/venv/lib/python3.13/site-packages/google/adk/flows/llm_flows/base_llm_flow.py", line 465, in _preprocess_async
    async for event in agen:
      yield event
  File "/Users/Shekhar/cosmos-adk-v3/venv/lib/python3.13/site-packages/google/adk/flows/llm_flows/contents.py", line 50, in run_async
    llm_request.contents = _get_contents(
                           ~~~~~~~~~~~~~^
        invocation_context.branch,
        ^^^^^^^^^^^^^^^^^^^^^^^^^^
        invocation_context.session.events,
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        agent.name,
        ^^^^^^^^^^^
    )
    ^
  File "/Users/Shekhar/cosmos-adk-v3/venv/lib/python3.13/site-packages/google/adk/flows/llm_flows/contents.py", line 354, in _get_contents
    events_to_process = _process_compaction_events(raw_filtered_events)
  File "/Users/Shekhar/cosmos-adk-v3/venv/lib/python3.13/site-packages/google/adk/flows/llm_flows/contents.py", line 265, in _process_compaction_events
    compaction.start_timestamp is not None
    ^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'dict' object has no attribute 'start_timestamp'

[llalitkumarrr]

Hello @MahorShekhar ,

Could you please provide more information to help us understand this issue better? A minimal reproducible code example would be very helpful.

Also, if you are not already using the latest version, please upgrade to google-adk==1.21.0. You may also find this page in docs useful.

[MahorShekhar]

hi @llalitkumarrr this issue is related to this one : #3707

[llalitkumarrr]

We had two releases after this, could you please try to test with latest version?

[ryanovas]

@llalitkumarrr There are multiple issues all relating to the same bug originally reported here: #3487

It is still an issue in 1.21.

There is a pull request open that fixes this here: #3490

This has been an issue for some time and multiple tickets created for it:

• DatabaseSessionService.to_event() fails to deserialize nested Pydantic models (EventCompaction) when using EventsCompactionConfig #4047
• BUG - Event Compaction model validate error #3707
• EventCompaction deserialized as dict instead of Pydantic model in DatabaseSessionService #3633
• AttributeError in Events Compaction with DatabaseSessionService #3530

[llalitkumarrr]

Hi @MahorShekhar ,

We are currently analyzing this issue. Could you please provide the reproduction steps and a minimal reproducible code snippet? That would help us a lot.

[nicwang119]

Same issue as above

---

Hello, @llalitkumarrr, I encountered the same error. I opened an issue yesterday, but it hasn’t been very helpful so far. I believe this may be the same issue described in #4082.

I'm using google-adk version 1.21.0, and I also tried 1.20.0 and 1.19.0, but the issue persists across all of them.

The code below reproduces the error — it was run entirely in a single cell on a Kaggle CPU notebook. The problem seems related to compaction, which is triggered at turn 4, as I set compaction_interval = 3.

Let me know if you want to add any logs or stack trace reference as well.

Thanks.

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Code snippet

code_snippet.txt

Code response

code_response1.txt