* .NET: Foundry agent-endpoint constructor uses ProjectOpenAIClient directly to fix hosted-agent URL routing
Fixes the experimental FoundryAgent(Uri agentEndpoint, AuthenticationTokenProvider, ...)
constructor so it actually works against Foundry hosted agents.
The previous implementation routed through AzureAIProjectChatClient, which
internally called aiProjectClient.GetProjectOpenAIClient().GetProjectResponsesClientForAgent(...).
For an agent-endpoint URL of the canonical shape
https://<host>/api/projects/<project>/agents/<agentName>/endpoint/protocols/openai
the chain produced
POST https://<host>/api/projects/<project>/openai/v1/responses
(project-level path, no /agents/ segment). The Foundry service rejects this with
HTTP 400 "Hosted agents can only be called through the agent endpoint:
.../agents/<agentName>/endpoint/protocols/openai/responses".
The constructor also extracted the agent name via
agentEndpoint.Segments[^1].TrimEnd('/'), which returns "openai" (the last segment),
not the agent name.
What changed
- Public ctor signature: clientOptions parameter type changed from
AIProjectClientOptions? to ProjectOpenAIClientOptions?. The constructor is
fundamentally building a ProjectOpenAIClient; accepting AIProjectClientOptions
was a leaky abstraction whose translation silently dropped any pipeline
policies the caller added via AddPolicy(...). With the direct type, caller
policies pass through to the per-agent traffic verbatim.
- Per-agent client construction: `new ProjectOpenAIClient(BearerTokenPolicy, ProjectOpenAIClientOptions)`
with Endpoint and AgentName set, then `GetProjectResponsesClient().AsIChatClient()`.
The SDK auto-appends ?api-version=v1 when AgentName is set.
- New private static ParseAgentEndpoint helper: single source of truth for both
agent-name extraction and project-root derivation. Tolerates trailing slash,
case variants on /agents/ and the suffix segment, strips query/fragment, and
throws ArgumentException with paramName=nameof(agentEndpoint) for malformed input.
- Project-level client (used by CreateConversationSessionAsync) is built fresh
from the derived project root with primitive properties copied
(RetryPolicy/NetworkTimeout/Transport/UserAgentApplicationId) plus MEAI UA.
- New GetService<ProjectOpenAIClient>() entry alongside the existing
GetService<AIProjectClient>() (the latter returns null in agent-endpoint mode
since no AIProjectClient is constructed on that path).
- Endpoint and AgentName on caller-supplied ProjectOpenAIClientOptions are
overridden by values derived from agentEndpoint.
Compatibility
- FoundryAgent is [Experimental(OPENAI001)]. No GA surface touched. The Foundry
project does not maintain PublicAPI.*.txt baselines so there is no shipped
baseline to update.
- The Microsoft.Agents.AI.Foundry csproj pins
Azure.AI.Projects to VersionOverride 2.1.0-beta.1 (matching what the IT and
hosting projects already use); the central pin in Directory.Packages.props
stays at 2.0.0.
- WireClientHeaders from PR #5652 is invoked on the agent-endpoint path so
per-call x-client-* headers behave identically across both ctors.
Tests
- 23 new unit tests in FoundryAgentTests.cs:
- 12 for the agent-endpoint constructor (URL routing for non-streaming and
streaming, conversations URL shape, MEAI UA stamping, caller-policy
passthrough on the per-agent pipeline, Endpoint/AgentName override
semantics, GetService matrix, ProjectOpenAIClient propagation,
UserAgentApplicationId propagation, null-arg validation, ID/Name slug)
- 9 for ParseAgentEndpoint (standard shape, trailing slash, casing,
sovereign-cloud host without /api/projects/ literal prefix, special chars
in agent name, query/fragment stripping, three negative cases)
- 2 null-arg tests for the public ctor
- All 250 Microsoft.Agents.AI.Foundry.UnitTests pass (was 221 baseline plus
29 from PR #5652 plus 23 new in this PR equals 273; pre-existing tests
collapsed by the rebase merge keep the total at 250).
- All 225 Microsoft.Agents.AI.Foundry.Hosting.UnitTests pass; no behavioral
change to the hosting layer.
- dotnet build clean across net8/9/10/netstandard2.0/net472 with
TreatWarningsAsErrors=true.
- dotnet format --verify-no-changes clean for the touched src and test projects.
* .NET: Bump central Azure.AI.Projects pin to 2.1.0-beta.1 and flip Microsoft.Agents.AI.Foundry to preview
Required to fix the NU1109 downgrade chain that broke CI on the agent-endpoint
constructor rewire (#5677). Microsoft.Agents.AI.Foundry now depends on
ProjectOpenAIClientOptions.AgentName and the (AuthenticationPolicy, options)
constructor that only exist in Azure.AI.Projects 2.1.0-beta.1.
Changes:
* Directory.Packages.props: Azure.AI.Projects 2.0.0 -> 2.1.0-beta.1.
* Microsoft.Agents.AI.Foundry.csproj: drop IsReleased=true so the package ships
as preview (matches the beta SDK we now depend on). Add a comment noting the
flip is temporary and should revert once Azure.AI.Projects ships a stable
2.1.0.
* Drop redundant VersionOverride="2.1.0-beta.1" from the 10 csprojs that had it
as a workaround; the central pin now suffices.
Verified:
* dotnet build agent-framework-dotnet.slnx --warnaserror clean across all TFMs.
* Microsoft.Agents.AI.Foundry.UnitTests 250/250 pass.
* Microsoft.Agents.AI.Foundry.Hosting.UnitTests 211/211 pass.
* dotnet format --verify-no-changes clean for the touched src and test projects.
Welcome to Microsoft Agent Framework!
Microsoft Agent Framework (MAF) is an open, multi-language framework for building production-grade AI agents and multi-agent workflows in .NET and Python.
Microsoft Agent Framework is built for teams taking agents from prototype to production. It provides a consistent foundation for building, orchestrating, and operating agent systems across Python and .NET, while keeping architecture choices open as requirements evolve, and supports a broad ecosystem including Microsoft Foundry, Azure OpenAI, OpenAI, and the GitHub Copilot SDK, with samples and hosting patterns for both local development and cloud deployment.
Watch the full Agent Framework introduction (30 min)
Is this the right framework for you?
MAF is a strong fit if you:
- are building agents and workflows you expect to run in production,
- need orchestration beyond a single prompt or stateless chat loop,
- want graph-based patterns such as sequential, concurrent, handoff, and group collaboration,
- care about durability, restartability, observability, governance, or human-in-the-loop control,
- need provider flexibility so your architecture can evolve without major rewrites.
Key Features
Explore new MAF capabilities and real implementation patterns on the official blog.
- Python and C#/.NET Support: Full framework support for both Python and C#/.NET implementations with consistent APIs
- Multiple Agent Provider Support: Support for various LLM providers with more being added continuously
- Middleware: Flexible middleware system for request/response processing, exception handling, and custom pipelines
- Orchestration Patterns & Workflows: Build multi-agent systems with graph-based workflows supporting sequential, concurrent, handoff, and group collaboration patterns; includes checkpointing, streaming, human-in-the-loop, and time-travel
- Foundry Hosted Agents (new): Deploy and host your agents to Foundry-hosted infrastructure with just 2 additional lines of code
- Observability: Built-in OpenTelemetry integration for distributed tracing, monitoring, and debugging
- Declarative Agents: Define agents using YAML for faster setup and versioning
- Agent Skills: Build domain-specific knowledge bases from multiple sources—files, inline code, class libraries—for agents to discover and use
- AF Labs: Experimental packages for cutting-edge features including benchmarking, reinforcement learning, and research initiatives
- DevUI: Interactive developer UI for agent development, testing, and debugging workflows
Table of Contents
Getting Started
Installation
Python
pip install agent-framework
# This will install all sub-packages, see `python/packages` for individual packages.
# It may take a minute on first install on Windows.
.NET
dotnet add package Microsoft.Agents.AI
# For Foundry integration (used in the .NET quickstart below):
dotnet add package Microsoft.Agents.AI.Foundry
dotnet add package Azure.AI.Projects
dotnet add package Azure.Identity
Learning Resources
- Overview - High level overview of the framework
- Quick Start - Get started with a simple agent
- Tutorials - Step by step tutorials
- User Guide - In-depth user guide for building agents and workflows
- Migration from Semantic Kernel - Guide to migrate from Semantic Kernel
- Migration from AutoGen - Guide to migrate from AutoGen
Quickstart
Basic Agent - Python
Create a simple Azure Responses Agent that writes a haiku about the Microsoft Agent Framework
# pip install agent-framework
# Use `az login` to authenticate with Azure CLI
import os
import asyncio
from agent_framework import Agent
from agent_framework.foundry import FoundryChatClient
from azure.identity import AzureCliCredential
async def main():
# Initialize a chat agent with Microsoft Foundry
# the endpoint, deployment name, and api version can be set via environment variables
# or they can be passed in directly to the FoundryChatClient constructor
agent = Agent(
client=FoundryChatClient(
credential=AzureCliCredential(),
# project_endpoint=os.environ["FOUNDRY_PROJECT_ENDPOINT"],
# model=os.environ["FOUNDRY_MODEL_DEPLOYMENT_NAME"],
),
name="HaikuAgent",
instructions="You are an upbeat assistant that writes beautifully.",
)
print(await agent.run("Write a haiku about Microsoft Agent Framework."))
if __name__ == "__main__":
asyncio.run(main())
Basic Agent - .NET
Create a simple Agent, using Microsoft Foundry that writes a haiku about the Microsoft Agent Framework
// This sample shows how to create and run a basic agent with AIProjectClient.AsAIAgent(...).
using Azure.AI.Projects;
using Azure.Identity;
using Microsoft.Agents.AI;
string endpoint = Environment.GetEnvironmentVariable("AZURE_AI_PROJECT_ENDPOINT") ?? throw new InvalidOperationException("AZURE_AI_PROJECT_ENDPOINT is not set.");
string deploymentName = Environment.GetEnvironmentVariable("AZURE_AI_MODEL_DEPLOYMENT_NAME") ?? "gpt-5.4-mini";
AIAgent agent =
new AIProjectClient(new Uri(endpoint), new DefaultAzureCredential())
.AsAIAgent(model: deploymentName, instructions: "You are an upbeat assistant that writes beautifully.", name: "HaikuAgent");
// Once you have the agent, you can invoke it like any other AIAgent.
Console.WriteLine(await agent.RunAsync("Write a haiku about Microsoft Agent Framework."));
More Examples & Samples
Python
- Getting Started: progressive tutorial from hello-world to hosting
- Agent Concepts: deep-dive samples by topic (tools, middleware, providers, etc.)
- Workflows: workflow creation and integration with agents
- Hosting: A2A, Azure Functions, Durable Task hosting
- End-to-End: full applications, evaluation, and demos
.NET
- Getting Started: progressive tutorial from hello agent to hosting
- Agent Concepts: basic agent creation and tool usage
- Agent Providers: samples showing different agent providers
- Workflows: advanced multi-agent patterns and workflow orchestration
- Hosting: A2A, Durable Agents, Durable Workflows
- End-to-End: full applications and demos
Community & Feedback
- Found a bug? File a GitHub issue to help us improve.
- Enjoying MAF?
to show your support and help others discover the project.
- Have questions? Join our Discord or visit weekly office hours.
Troubleshooting
Authentication
| Problem | Cause | Fix |
|---|---|---|
| Authentication errors when using Azure credentials | Not signed in to Azure CLI | Run az login before starting your app |
| API key errors | Wrong or missing API key | Verify the key and ensure it's for the correct resource/provider |
Tip:
DefaultAzureCredentialis convenient for development but in production, consider using a specific credential (e.g.,ManagedIdentityCredential) to avoid latency issues, unintended credential probing, and potential security risks from fallback mechanisms.
Environment Variables
For environment variable configuration specific to each sample, refer to the README in the sample directory (Python samples | .NET samples).
Contributor Resources
Important Notes
Important
If you use Microsoft Agent Framework to build applications that operate with any third-party servers, agents, code, or non-Azure Direct models (“Third-Party Systems”), you do so at your own risk. Third-Party Systems are Non-Microsoft Products under the Microsoft Product Terms and are governed by their own third-party license terms. You are responsible for any usage and associated costs.
We recommend reviewing all data being shared with and received from Third-Party Systems and being cognizant of third-party practices for handling, sharing, retention and location of data. It is your responsibility to manage whether your data will flow outside of your organization’s Azure compliance and geographic boundaries and any related implications, and that appropriate permissions, boundaries and approvals are provisioned.
You are responsible for carefully reviewing and testing applications you build using Microsoft Agent Framework in the context of your specific use cases, and making all appropriate decisions and customizations. This includes implementing your own responsible AI mitigations such as metaprompt, content filters, or other safety systems, and ensuring your applications meet appropriate quality, reliability, security, and trustworthiness standards. See also: Transparency FAQ
