Python: [Bug]: `FoundryAgent` (Responses API) Does Not Surface `oauth_consent_request` as a CUSTOM AG-UI Event

[djw-bsn]

Description

When a Foundry agent is backed by an MCP server that requires OAuth consent, FoundryAgent (which uses the Responses API) silently drops the oauth_consent_request stream events. The consent link is never surfaced to the caller.

This is a regression from AzureAIClient (Assistants API), which correctly emits a CUSTOM AG-UI event with name="oauth_consent_request" that callers can intercept.

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Environment

Client	agent_framework.foundry.FoundryAgent (new)
Upstream API	Azure OpenAI Responses API
MCP server	Databricks Genie MCP server requiring OAuth consent
AG-UI layer	agent_framework_ag_ui

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Steps to Reproduce

1. Configure a Foundry agent with an MCP server that requires OAuth consent (e.g. Databricks Genie MCP server)
2. Instantiate the agent using FoundryAgent / FoundryChatClient
3. Send a request that triggers MCP tool listing - causing the MCP server to require OAuth

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Expected Behaviour

A CUSTOM AG-UI event is emitted with:

{
  "type": "CUSTOM",
  "name": "oauth_consent_request",
  "value": {
    "consent_link": "https://[consent-host]/login?data=..."
  }
}

This is the behaviour produced by AzureAIClient (Assistants API path) and is what downstream callers depend on to surface the consent link to the user.

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Actual Behaviour

The Responses API stream delivers two OAuth-related events:

response.output_item.added  ->  item.type = 'oauth_consent_request'  (contains consent_link)
response.oauth_consent_requested  ->  (also contains consent_link)

Both fall through to the case _: catchall in RawOpenAIChatClient's streaming event handler:

case _:
    logger.debug("Unparsed event of type: %s: %s", event.type, event)

Neither event is translated into a CUSTOM AG-UI event. The consent link is never surfaced to the caller. The stream completes normally with no output and no error.

---

Evidence

Broken (FoundryAgent - Responses API)

[DEBUG] agent_framework.openai - Unparsed event of type: response.output_item.added:
    ResponseOutputItemAddedEvent(item=ResponseOutputMessage(..., type='oauth_consent_request',
    consent_link='https://[consent-host]/login?data=...'), ...)

[DEBUG] agent_framework.openai - Unparsed event of type: response.oauth_consent_requested:
    ResponseAudioDeltaEvent(..., consent_link='https://...', ...)

[DEBUG] backend - Stream completed normally

No CUSTOM event. No consent link surfaced. Stream exits silently.

Working (AzureAIClient - Assistants API)

[DEBUG] agent_framework_ag_ui - Emitting CUSTOM AG-UI event: name='oauth_consent_request' value={'consent_link': 'https://[consent-host]/login?data=...'}

CUSTOM AG-UI event emitted correctly. Consent link surfaced and forwarded to the frontend.

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Root Cause

RawOpenAIChatClient's streaming event handler (the match event.type block) has no case for:

• "response.oauth_consent_requested"
• "response.output_item.added" where item.type == "oauth_consent_request"

These event types are present in the commented-out section of the handler (confirming awareness), but no implementation exists:

# ResponseMcpListToolsCompletedEvent,
# ResponseMcpListToolsFailedEvent,
# ResponseMcpListToolsInProgressEvent,

The agent_framework_ag_ui layer does handle the equivalent signal from the Assistants API and emits a CUSTOM event - but the Responses API path has no equivalent handling.

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Impact

Any agent migrated from AzureAIClient -> FoundryAgent that uses an MCP server with OAuth consent will silently break. The migration is actively encouraged (the deprecation warning on AzureAIClient reads: "Use OpenAIChatClient with an AsyncAzureOpenAI client, or FoundryChatClient for Foundry projects"), making this a migration blocker.

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Fix Required

In RawOpenAIChatClient's streaming event handler, add handling for the OAuth consent events and emit an appropriate signal - either:

1. A CUSTOM AG-UI event with name="oauth_consent_request" and value={"consent_link": "..."}, consistent with the Assistants API behaviour; or
2. A dedicated exception type (e.g. OAuthConsentRequiredException) that callers can catch

Option 1 is preferred for backward compatibility with existing callers.

case "response.oauth_consent_requested":
    consent_link = getattr(event, "consent_link", None)
    if consent_link:
        contents.append(
            Content.custom(name="oauth_consent_request", value={"consent_link": consent_link})
        )

---

Workaround

Revert to AzureAIClient for any agent that requires MCP OAuth consent until this is resolved.

# Temporary workaround - revert to deprecated client
from agent_framework.azure import AzureAIClient

Code Sample

Error Messages / Stack Traces

Package Versions

agent-framework-core==1.0.0rc6, agent-framework-foundry==1.0.0rc6, agent_framework_ag_ui==1.0.0b260330

Python Version

Python 3.12

Additional Context

No response