Python: OpenAI store=True can silently bypass external HistoryProvider persistence

[rg-ve]

Summary

When using the Python SDK with OpenAIChatClient, an external HistoryProvider such as CosmosHistoryProvider, and require_per_service_call_history_persistence=True, external history can be silently skipped unless callers explicitly set store=False in ChatOptions.

This is surprising because the agent is configured with an external history provider and asks for per-service-call persistence, but no provider rows are written and no warning/error is surfaced.

Repro shape

from agent_framework import Agent, AgentSession, ChatOptions
from agent_framework.openai import OpenAIChatClient
from agent_framework_azure_cosmos import CosmosHistoryProvider

history = CosmosHistoryProvider(...valid endpoint/db/container/credential...)
client = OpenAIChatClient(api_key=..., model="gpt-5.5-pro")

async with history:
    async with Agent(
        client=client,
        name="HistoryRepro",
        instructions="Answer briefly.",
        context_providers=[history],
        require_per_service_call_history_persistence=True,
        default_options=ChatOptions(
            model="gpt-5.5-pro",
            max_tokens=512,
            reasoning={"effort": "high"},
            # store=False fixes the issue. Omitting it writes no external rows.
        ),
    ) as agent:
        session = AgentSession(session_id="debug-openai-history")
        async for _ in agent.run("Remember BLUE-COSMOS-913. Reply ok.", stream=True, session=session):
            pass

Observed without store=False:

• The model call succeeds.
• A second turn with the same in-process session may recall successfully.
• CosmosHistoryProvider writes zero rows.
• There is no warning that external history was bypassed.

Observed with store=False:

• Cosmos rows are written as expected.
• A second turn can recall from SDK/Cosmos history.

Suspected cause

OpenAIChatClient.STORES_BY_DEFAULT=True. In Agent._resolve_per_service_call_history_providers(...), service-side storage means no per-service-call history middleware is installed. Later, _run_after_providers(...) still skips HistoryProvider instances because require_per_service_call_history_persistence is true. The combination results in no external history writes.

Expected behavior

At least one of these should happen:

1. require_per_service_call_history_persistence=True plus external HistoryProvider should force local/external persistence or set store=False for OpenAI automatically.
2. The SDK should raise a configuration error when OpenAI service-side storage and external per-service-call history persistence conflict.
3. The SDK should log a clear warning that external HistoryProvider persistence is disabled because service-side OpenAI storage is active.

Silent zero-row external history is hard to diagnose in production.

Workaround

Set store=False in OpenAI ChatOptions when external SDK history is the source of truth.

Thanks.