DevUI Interface Breaks with Azure AI Agents

[dragospadurariu]

When using Azure AI Agents with DevUI, the interface breaks during execution. The logs show:

Response status: 200 Response headers: 'Content-Type': 'text/event-stream; charset=utf-8' ... [CANCELLATION] Execution cancelled via CancelledError for resp_9af4a376 [CANCELLATION] Stream cancelled for resp_9af4a376

The DevUI Events panel shows thousands of output_text.delta events (2629+ in my case), and then the execution gets cancelled.

Here is the code I am using:

from agent_framework import WorkflowBuilder
from agent_framework.azure import AzureAIAgentClient

from src.executors.document_ingestion import DocumentIngestionExecutor
from src.agents.requirements_extraction import create_requirements_extraction_agent


def create_workflow(
    chat_client: AzureAIAgentClient,
    as_agent: bool = True
):
    """

    This workflow processes uploaded documents and extracts structured requirements.

    Workflow Flow:
        User Input → DocumentIngestion → RequirementsExtraction → User Output (JSON)

    Args:
        chat_client: Azure AI agent client for creating agents
        as_agent: If True, returns workflow.as_agent() for compatibility with container mode

    Returns:
        Workflow or workflow agent depending on as_agent parameter
    """

    # Step 1: Create the document ingestion executor
    document_ingestion = DocumentIngestionExecutor()

    # Step 2: Create the requirements extraction agent
    requirements_extraction = create_requirements_extraction_agent(chat_client)

    # Step 3: Build the workflow
    workflow = (
        WorkflowBuilder(
            name="Workflow",
            description="Extracts structured requirements from documents",
        )
        .set_start_executor(document_ingestion)
        .add_edge(document_ingestion, requirements_extraction)
        .build()
    )

    return workflow.as_agent() if as_agent else workflow

[victordibia]

Thanks for the issue and reproducible example.
We will review and address soon.