Conformance testing produces `AttributeError: 'NoneType' object has no attribute 'recordings'`

[wbyoung]

🔴 Required Information

Describe the Bug:

Conformance testing (adk conformance test) raises an error with a basic, newly created app.

Steps to Reproduce:
Run the following:

python3.14 -m venv venv
source venv/bin/activate
pip install google-adk==2.9.1
adk create example --model gemini-3.5-flash --project na --region us-central1
rm example/.env
export GOOGLE_GENAI_USE_ENTERPRISE=1
export GOOGLE_APPLICATION_CREDENTIALS="/path/to/google-credentials.json"                         
mkdir -p tests/core/simple_qa
cat > tests/core/simple_qa/spec.yaml <<EOF
description: 'Verifies the agent can respond.'
agent: 'example'
user_messages:
  - text: 'What is the timezone for Annapolis, MD?'
EOF
adk web --port 8000 --extra_plugins=google.adk.cli.plugins.recordings_plugin.RecordingsPlugin

In another shell:

source venv/bin/activate
export GOOGLE_GENAI_USE_ENTERPRISE=1
export GOOGLE_APPLICATION_CREDENTIALS="/path/to/google-credentials.json"                         
adk conformance record none
adk conformance test

The result will include an error, Replay verification failed: AttributeError: 'NoneType' object has no attribute 'recordings'.

Expected Behavior:

The newly generated conformance test will run and pass.

Observed Behavior:

An error was generated:

==================================================
Running ADK conformance tests in replay mode...
==================================================

Found 1 test cases to run in replay mode for streaming mode StreamingMode.NONE.

Running core/simple_qa... ✗ FAIL
Error: Replay verification failed: AttributeError: 'NoneType' object has no attribute 'recordings'
Skipping core/simple_qa: no recordings
No test cases found!

==================================================
CONFORMANCE TEST SUMMARY FOR STREAMING MODE: StreamingMode.NONE
==================================================
Total tests: 1
Passed: 0
Failed: 1
Success rate: 0.0%

Failed tests:

✗ core/simple_qa

  Replay verification failed: AttributeError: 'NoneType' object has no attribute 'recordings'
Error: 1 test(s) failed

Environment Details:

• ADK Library Version (pip show google-adk): 2.9.1
• Desktop OS:** Fedora 44
• Python Version (python -V): 3.14.7

Model Information:

• Are you using LiteLLM: No
• Which model is being used: gemini-3.5-flash

---

🟡 Optional Information

Providing this information greatly speeds up the resolution process.

Regression:
Did this work in a previous version of ADK? No

Logs:

generated-recordings.yaml

recordings:
  - user_message_index: 0
    agent_name: root_agent
    llm_recording:
      llm_request:
        model: gemini-3.5-flash
        contents:
          - parts:
              - text: What is the timezone for Annapolis, MD?
            role: user
        config:
          http_options:
            headers:
              x-goog-api-client: google-adk/2.9.1 gl-python/3.14.7
              user-agent: google-adk/2.9.1 gl-python/3.14.7
          system_instruction: |-
            Answer user questions to the best of your knowledge

            You are an agent. Your internal name is "root_agent". The description about you is "A helpful assistant for user questions.".
          labels:
            adk_agent_name: root_agent
        live_connect_config:
          input_audio_transcription: {}
          output_audio_transcription: {}
      llm_responses:
        - model_version: gemini-3.5-flash
          content:
            parts:
              - text: "Annapolis, Maryland is in the **Eastern Time Zone** (ET). \n\n* **Eastern Standard Time (EST):** UTC-5 (used during the autumn and winter months, from November to March)\n* **Eastern Daylight Time (EDT):** UTC-4 (used during the spring and summer months, from March to November)"
                thought_signature: AY89a18D1H7owwvbYHARbqdzBHEWACGN8nRolf-qEwnR4abFfSCQpt-LHP69IM9N4q-yT43si9lNC6qYlhq57v0kw0dH_FBXAdmgWDOnsR-D5Zieg18FQxO5L1cARS2iEHjOMVKEOycrmn5r1jK_VTrWe_7vW5sdyD4RTuTGVASWcK_k0mlYbC75kke3tI-byYZHJxX2DoxDmtsbYsIcQ3M46ioQMCAbl7goJqL5GkLFuaGs2GkxYM4RadtDpSYTL94_5SCMBahmrQHg40KKE17CmHLKnk44f7fAryYXDJI4O4Yyx7HjZNTNdS-gIWHWuY_QiEkjDB6_FGBSG0_cUkDmsHU02NFxZK55HUgbkaPP1LxE2oQNDa6JTbYOFhKvCRVeWD1lycgLMi3XVhgqMHMN19X2_tvq4eDzVPJPUo3f4NhpYDcglEREE9CqP1kntOfQZljfe2DlNetyxMaMGrsf-m5AECQ2NHxdr3HYj5m4z14MC1YFfxf0dmLEcTzdaDgVrUo2KVe9-mkIJfoTpVP7s-jV45vrGn2eI-X9a-C57SJCuG4ruCEB0gFs9PT-EaRkCeXbfKFtNJGP7VvAcTsDF3m2Pa9zxymkKCxHIcmEg0i10smcEXr3Fvy-uyXxZBrykiNYNdYnGPJLQ-G65ZJyEqY8CHrHNiwMDIGpZ4_XlKrBA9rW4cklI7EjnLF-xqtWkWwahYJ35gtMOq8Q6qrF-TdRUV-e1l7UMz6Wa3T63fUPL07Ol19VuFZxw_6e13VEPC98yDHpMqMJx3Io66axlFd5ZVl-QfI1Xgb0mSJY3C6OPCOrUsZta4Lm_5zrvgmUT-hz6Mx-ZGnqGvUjPvIKXT2ONlTEc7sYgwEB1B6JY31ZJZQ19WnPU_kdC4NFFWL_tyy4DSPtRGEWWg8b_Enk1NE2JTPYrRxkGIR_biqtZcXpWkEW-RV89OtOABSNQEuzChZVPka8Y-jX2PaATzraIwLb2m4wDX5rKoq8HLKZ9e6PA0FXsEvoyIVMjM8_7Jg58BItcb-5FBkCAbYH7Tokr1AZeQ6M77r2xi6Vd8JK
            role: model
          finish_reason: STOP
          usage_metadata:
            candidates_token_count: 71
            candidates_tokens_details:
              - modality: TEXT
                token_count: 71
            prompt_token_count: 46
            prompt_tokens_details:
              - modality: TEXT
                token_count: 46
            thoughts_token_count: 185
            total_token_count: 302
            traffic_type: ON_DEMAND

generated-session.yaml

id: b60df26d-2f64-44aa-b07f-e9d9d6a48081
app_name: example
user_id: adk_conformance_test_user
state: {}
events:
  - content:
      parts:
        - text: What is the timezone for Annapolis, MD?
      role: user
    invocation_id: e-fca5ef94-8fcd-4b0d-96b1-9ee2337ee628
    author: user
    actions:
      state_delta: {}
    id: b8fee991-6044-4e33-a623-8bdd32efc242
    timestamp: 1789501210.1484904
  - model_version: gemini-3.5-flash
    content:
      parts:
        - text: "Annapolis, Maryland is in the **Eastern Time Zone** (ET). \n\n* **Eastern Standard Time (EST):** UTC-5 (used during the autumn and winter months, from November to March)\n* **Eastern Daylight Time (EDT):** UTC-4 (used during the spring and summer months, from March to November)"
          thought_signature: AY89a18D1H7owwvbYHARbqdzBHEWACGN8nRolf-qEwnR4abFfSCQpt-LHP69IM9N4q-yT43si9lNC6qYlhq57v0kw0dH_FBXAdmgWDOnsR-D5Zieg18FQxO5L1cARS2iEHjOMVKEOycrmn5r1jK_VTrWe_7vW5sdyD4RTuTGVASWcK_k0mlYbC75kke3tI-byYZHJxX2DoxDmtsbYsIcQ3M46ioQMCAbl7goJqL5GkLFuaGs2GkxYM4RadtDpSYTL94_5SCMBahmrQHg40KKE17CmHLKnk44f7fAryYXDJI4O4Yyx7HjZNTNdS-gIWHWuY_QiEkjDB6_FGBSG0_cUkDmsHU02NFxZK55HUgbkaPP1LxE2oQNDa6JTbYOFhKvCRVeWD1lycgLMi3XVhgqMHMN19X2_tvq4eDzVPJPUo3f4NhpYDcglEREE9CqP1kntOfQZljfe2DlNetyxMaMGrsf-m5AECQ2NHxdr3HYj5m4z14MC1YFfxf0dmLEcTzdaDgVrUo2KVe9-mkIJfoTpVP7s-jV45vrGn2eI-X9a-C57SJCuG4ruCEB0gFs9PT-EaRkCeXbfKFtNJGP7VvAcTsDF3m2Pa9zxymkKCxHIcmEg0i10smcEXr3Fvy-uyXxZBrykiNYNdYnGPJLQ-G65ZJyEqY8CHrHNiwMDIGpZ4_XlKrBA9rW4cklI7EjnLF-xqtWkWwahYJ35gtMOq8Q6qrF-TdRUV-e1l7UMz6Wa3T63fUPL07Ol19VuFZxw_6e13VEPC98yDHpMqMJx3Io66axlFd5ZVl-QfI1Xgb0mSJY3C6OPCOrUsZta4Lm_5zrvgmUT-hz6Mx-ZGnqGvUjPvIKXT2ONlTEc7sYgwEB1B6JY31ZJZQ19WnPU_kdC4NFFWL_tyy4DSPtRGEWWg8b_Enk1NE2JTPYrRxkGIR_biqtZcXpWkEW-RV89OtOABSNQEuzChZVPka8Y-jX2PaATzraIwLb2m4wDX5rKoq8HLKZ9e6PA0FXsEvoyIVMjM8_7Jg58BItcb-5FBkCAbYH7Tokr1AZeQ6M77r2xi6Vd8JK
      role: model
    finish_reason: STOP
    usage_metadata:
      candidates_token_count: 71
      candidates_tokens_details:
        - modality: TEXT
          token_count: 71
      prompt_token_count: 46
      prompt_tokens_details:
        - modality: TEXT
          token_count: 46
      thoughts_token_count: 185
      total_token_count: 302
      traffic_type: ON_DEMAND
    invocation_id: e-fca5ef94-8fcd-4b0d-96b1-9ee2337ee628
    author: root_agent
    node_info:
      path: root_agent@1
    id: eb86c580-e504-4696-8947-ea3e4f139b8d
    timestamp: 1789501210.1803176
last_update_time: 1789501210.1803176

Screenshots / Video:
N/A

Additional Context:
Add any other context about the problem here.

Minimal Reproduction Code:
See above.

How often has this issue occurred?:

Always

[chelsealong]

Picking this one up now — opening a PR shortly. Flagging it here so nobody duplicates the work; if someone is already on it, say so and I will drop mine.

[surajksharma07]

@wbyoung Root cause is that adk conformance test needs the server started with ReplayPlugin loaded not just RecordingsPlugin (the latter is only for record mode). Could you restart adk web with both plugins passed to --extra_plugins (RecordingsPlugin and ReplayPlugin) and confirm adk conformance test runs clean after that?

Separately @chelsealong already has #7129 up which turns this into a proper actionable error instead of the raw AttributeError so no need to open a second PR for that part, we'll get that reviewed and merged.