Python: Allow AzureOpenAIResponsesClient creation with Foundry project endpoint

[Copilot]

Motivation and Context

AzureOpenAIResponsesClient only supported direct Azure OpenAI endpoint configuration. Users working with Azure AI Foundry projects had no way to create a responses client from a project endpoint or AIProjectClient, unlike AzureAIClient which already supports this.

Description

Adds project_client and project_endpoint parameters to AzureOpenAIResponsesClient, enabling client creation via Azure AI Foundry projects.

• project_client: Pass an existing AIProjectClient directly
• project_endpoint + credential: Auto-creates an AIProjectClient from the endpoint
• Both paths call project_client.get_openai_client() to obtain the AsyncOpenAI client, which is then passed through the existing async_client code path
• azure-ai-projects is lazily imported — no new hard dependency on the core package

from azure.identity import DefaultAzureCredential
from agent_framework.azure import AzureOpenAIResponsesClient

# From project endpoint
client = AzureOpenAIResponsesClient(
    project_endpoint="https://your-project.services.ai.azure.com",
    deployment_name="gpt-4o",
    credential=DefaultAzureCredential(),
)

# Or from an existing AIProjectClient
from azure.ai.projects.aio import AIProjectClient

project_client = AIProjectClient(
    endpoint="https://your-project.services.ai.azure.com",
    credential=DefaultAzureCredential(),
)
client = AzureOpenAIResponsesClient(
    project_client=project_client,
    deployment_name="gpt-4o",
)

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the Contribution Guidelines
• All unit tests pass, and I have added new tests where possible
• Is this a breaking change? If yes, add "[BREAKING]" prefix to the title of the PR.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Python: [Feature]: Python: allow AzureOpenAIResponseClient creation with foundry project endpoint</issue_title>
<issue_description>### Description

We need to extend the AzureOpenAIResponseClient constructor to allow a project client or endpoint, which is then used to create the async openai client

Code Sample

Language/SDK

Python</issue_description>

<agent_instructions>Take the existing AzureOpenAIResponseClient, extend it with a similar set of parameters as the AzureAIClient to allow a second set of parameters to work, which is creating a azure.ai.projects.aio client, and then calling the get_openai_client method on that. This might not be needed directly, could be done through the _ensure_client feature of our OpenAI stack</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Python: [Feature]: Python: allow AzureOpenAIResponseClient creation with foundry project endpoint #3813

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[Copilot]

Pull request overview

Adds support for constructing AzureOpenAIResponsesClient via an Azure AI Foundry project (AIProjectClient or project endpoint), aligning it with existing Foundry-enabled client creation patterns elsewhere in the repo.

Changes:

• Added project_client / project_endpoint constructor parameters to AzureOpenAIResponsesClient and a helper to create an OpenAI client via Foundry projects.
• Added unit tests covering initialization via project client/endpoint and basic parameter validation.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 7 comments.

File	Description
python/packages/core/agent_framework/azure/_responses_client.py	Adds Foundry project-based client creation path and wiring into constructor.
python/packages/core/tests/azure/test_azure_responses_client.py	Adds tests for new constructor parameters and _create_client_from_project behavior.

[markwallace-microsoft]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
packages/core/agent_framework/azure
_responses_client.py	53	6	88%	188, 220, 288–291
_shared.py	81	7	91%	138–139, 202, 205, 218, 220, 230
packages/core/agent_framework/openai
_responses_client.py	611	80	86%	292–295, 299–300, 303–304, 310–311, 316, 329–335, 356, 364, 387, 550, 553, 608, 612, 614, 616, 618, 694, 704, 709, 752, 811, 825, 842, 855, 911, 996, 1001, 1005–1007, 1011–1012, 1035, 1104, 1126–1127, 1142–1143, 1161–1162, 1293–1294, 1310, 1312, 1391–1399, 1494, 1549, 1564, 1600–1601, 1603–1605, 1619–1621, 1631–1632, 1638, 1653
TOTAL	16809	2110	87%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
4012	225 💤	0 ❌	0 🔥	1m 8s ⏱️

[moonbox3]

@eavanvalkenburg do you want to address any of Copilot's feedback?