Model Context Protocol Support in Azure AI Foundry Agent Service is not working #93

marianosz · 2025-07-08T08:00:17Z

marianosz
Jul 8, 2025

Technical Feedback

Hi team.

I know that is a preview feature, but I build a MCP connection with my agent on past Friday 6/4 based on this announce https://devblogs.microsoft.com/foundry/announcing-model-context-protocol-support-preview-in-azure-ai-foundry-agent-service/ and was working fine.

But since yesterday, the call to the MCP tool started to generate errors.

The MCP server is online, I'm hitting it from an agent on VS code and is working as expected.

This is the redacted agent definition json

{
   "name":"...",
   "description":"...",
   "model":"gpt-4.1",
   "instructions":"...",
   "tools":[
      {
         "type":"mcp",
         "server_label":"MCPTools",
         "server_url":"...",
         "allowed_tools":null
      },
      {
         "type":"connected_agent",
         "connected_agent":{
            "name":"antother agent",
            "description":"...",
            "id":"..."
         }
      },
      {
         "type":"code_interpreter"
      }
   ],
   "top_p":1.0,
   "temperature":0.1,
   "tool_resources":{
      "code_interpreter":{
         "file_ids":[
            
         ]
      }
   },
   "metadata":{
      
   },
   "response_format":"auto"
}

This is the Input and Output data of the MCP call

{
id: "call_FOPKr6XiZyWacjNqUHZzTAwh"
type: "mcp"
arguments: "{"id":130974}"
name: "GetWork"
server_label: "WorkMCPTools"
output: null
}

This is the metadata of the MCP call

{
name: "mcp"
context: {
trace_id: "thread_16iGvh4PStZ6fyPB0JZs9qBW"
span_id: "call_FOPKr6XiZyWacjNqUHZzTAwh"
thread_id: "thread_16iGvh4PStZ6fyPB0JZs9qBW"
}
kind: "Tool"
parent_id: "step_llY8sk21nAYYKbkvai7Ri7X5"
start_time: "2025-07-08T07:35:11.000Z"
end_time: undefined
status: {
status_code: "Error"
description: "in_progress"
}
attributes: {
span_type: "Tool"
id: "call_FOPKr6XiZyWacjNqUHZzTAwh"
type: "mcp"
arguments: "{"id":130974}"
name: "GetWork"
server_label: "WorkMCPTools"
output: ""
}
}

And here is a screenshot of the thread steps

Desired Outcome

MCP server should be hit from the Agent, with the specific tool call.

Current Workaround

I don't have a workaround yet.

marianosz · 2025-07-09T09:22:34Z

marianosz
Jul 9, 2025
Author

Today the error is

{
name: "thread_dCRpnMjWHNmwPYT7o8TNSF6U"
context: {
trace_id: "thread_dCRpnMjWHNmwPYT7o8TNSF6U"
span_id: "thread_dCRpnMjWHNmwPYT7o8TNSF6U"
thread_id: "thread_dCRpnMjWHNmwPYT7o8TNSF6U"
}
attributes: {
span_type: "Thread"
}
kind: "Thread"
}

The MCP server is still working fine, tested from VS code agent

0 replies

gloveboxes · 2025-07-11T01:20:10Z

gloveboxes
Jul 11, 2025

Hey there @marianosz, I'm using the MCP support with the Agent Service as of a couple of days and it's working as expected.

Ensure you have SKD versions

azure-ai-agents==1.1.0b3
azure-ai-projects==1.0.0b12

Another thing I found was I needed to set my MCP Server to be stateless

mcp.settings.stateless_http = True

or

mcp = FastMCP("mcp-zava-sales-devcontainer", lifespan=app_lifespan, stateless_http=True)

atm, this worked, but it was just a hack and still verifying if this is correct approach...

Regards, Dave

9 replies

gloveboxes Jul 12, 2025

Also MCP and Agent Service SDK is definitely WIP and I didn't think there was support yet - but coming soon.

see Azure/azure-sdk-for-net#51137

amynic Jul 14, 2025
Maintainer

adding @elbruno who may have tried the /NET/C# versions

marianosz Jul 14, 2025
Author

Also took a look to https://github.com/Azure/azure-sdk-for-net/blob/d23c8d03cf6cb38f9008a5d65570fec5a871437a/sdk/ai/Azure.AI.Agents.Persistent/samples/Sample26_PersistentAgents_MCP.md

I'm hitting my Agent with

MCPToolResource mcpToolResource = new("WorkMCPTools")
{
    RequireApproval = MCPToolResourceRequireApproval.Never,
};

var toolResources = mcpToolResource.ToToolResources();

PersistentAgentThread thread = await agentsClient.Threads.CreateThreadAsync(
    toolResources: toolResources
);

so I'm not expecting an Approval request, but got error anyway.

Then I removed that and try to use as the example but I found that the async example is not using streaming.

I'm using agentsClient.Runs.CreateRunStreamingAsync but I never got an StreamingUpdate for an equivalent of SubmitToolApprovalAction toolApprovalAction

From the REST API the agent is working fine, but it keeps failing from the playground and the C# client code/

elbruno Jul 14, 2025

Also took a look to https://github.com/Azure/azure-sdk-for-net/blob/d23c8d03cf6cb38f9008a5d65570fec5a871437a/sdk/ai/Azure.AI.Agents.Persistent/samples/Sample26_PersistentAgents_MCP.md

I'm hitting my Agent with
MCPToolResource mcpToolResource = new("WorkMCPTools")
{
    RequireApproval = MCPToolResourceRequireApproval.Never,
};

var toolResources = mcpToolResource.ToToolResources();

PersistentAgentThread thread = await agentsClient.Threads.CreateThreadAsync(
    toolResources: toolResources
);
so I'm not expecting an Approval request, but got error anyway.

Then I removed that and try to use as the example but I found that the async example is not using streaming.

I'm using agentsClient.Runs.CreateRunStreamingAsync but I never got an StreamingUpdate for an equivalent of SubmitToolApprovalAction toolApprovalAction

From the REST API the agent is working fine, but it keeps failing from the playground and the C# client code/

Hey Mariano, that's weird, it should work (I mean that's the base of a couple of demos we have. I can't remember if we were using streaming mode in those scenarios).

Let me check the current scenarios and SDK and I'll let you know, we may need to change / update something.

Thanks for the heads-up!

marianosz Jul 15, 2025
Author

Adding some context, if I kick off my C# code to hit the MCP enabled Agent on Azure Foundry, taking a look to the thread info

Is not showing the agent id there, I'm not sure if is a bug or something is missing.

Doing the same but from REST API, I got the agent id info there and is working

gloveboxes · 2025-07-13T08:16:09Z

gloveboxes
Jul 13, 2025

@marianosz I see the https://www.nuget.org/packages/Azure.AI.Agents.Persistent/1.1.0-beta.4 came out yesterday and adds MCP support

1 reply

marianosz Jul 13, 2025
Author

Thanks

I did a test via REST API

https://learn.microsoft.com/en-us/azure/ai-foundry/agents/how-to/tools/model-context-protocol-samples

and is working, but is not working hitting it from C# run or the Agent Playground.

I think I will need to wait for a more robust implementation, but the weird situation is this was working on the first announced version.

Thanks!

gloveboxes · 2025-07-18T01:16:01Z

gloveboxes
Jul 18, 2025

@marianosz

Azure.AI.Agents.Persistent Version 1.1.0b4 has been released to https://www.nuget.org/packages/Azure.AI.Agents.Persistent/1.1.0-beta.4
The projects may be upgraded to use a new version by running command
dotnet add package Azure.AI.Agents.Persistent --version 1.1.0-beta.4
Features Added
Added support for Deep Research.
Added support for MCP.
Sample updates
Added sample for Deep Research.
Expose the GetVectorStoreFileBatchFiles and GetVectorStoreFileBatchFilesAsync methods.

Cheers Dave

3 replies

marianosz Jul 18, 2025
Author

Thanks, I tested that updated library from since day one with no luck.

On the Agent Playgroundstill got

On this thread run

Hitting from C# Code still got the same error, I don't have an error feedback, the streaming updates just abort, but If i took a look on the thread info I only got

I'm using the streaming API var threadRun = agentsClient.Runs.CreateRunStreamingAsync(threadId, existingAgent.Id);

This is my annotated agent configuration

    "id": "...",
    "object": "assistant",
    "created_at": 1751291657,
    "name": "...",
    "description": "...",
    "model": "gpt-4.1",
    "instructions": "...",
    "tools": [
        {
            "type": "mcp",
            "server_label": "WorkMCPTools",
            "server_url": "...",
            "allowed_tools": null,
            "require_approval": "never"
        },
        {
            "type": "connected_agent",
            "connected_agent": {
                "name": "...",
                "description": "...",
                "id": "..."
            }
        },
        {
            "type": "code_interpreter"
        }
    ],
    "top_p": 1.0,
    "temperature": 0.1,
    "tool_resources": {
        "code_interpreter": {
            "file_ids": []
        }
    },
    "metadata": {},
    "response_format": "auto"
}

So to capitalize, it works from Azure REST API following https://learn.microsoft.com/en-us/azure/ai-foundry/agents/how-to/tools/model-context-protocol-samples?pivots=rest steps.
It does't work from Agent Playground and C# code.

An important comment related to this, I tested with the same implementation on the announce day one, and worked without issues, both from Agent Playground and C# code.

My MCP server is an Azure Function, it works hitting from VS Code agent.

This is a summary of the streaming updates that I got for my last test

2025-07-18 11:40:10.1127|INFO|QueryWorkDetails started - SessionId: ..., Question: Dame un resumen de la obra id 1321 => 
2025-07-18 11:40:20.0722|DEBUG|Streaming update received: RunCreated - Raw: {
  "Value": {
    "RequiredActions": [],
    "Id": "...",
    "ThreadId": "...",
    "AssistantId": "...",
    "Status": {},
    "RequiredAction": null,
    "LastError": null,
    "Model": "gpt-4.1",
    "Instructions": "..."
    "Tools": [
      {
        "ServerLabel": "WorkMCPTools",
        "ServerUrl": "..."
        "AllowedTools": []
      },
      {
        "ConnectedAgent": {
          "Id": "..",
          "Name": "...",
          "Description": "..."
        }
      },
      {}
    ],
    "CreatedAt": "2025-07-18T09:40:18+00:00",
    "ExpiresAt": "2025-07-18T10:10:18+00:00",
    "StartedAt": null,
    "CompletedAt": null,
    "CancelledAt": null,
    "FailedAt": null,
    "IncompleteDetails": null,
    "Usage": null,
    "Temperature": 0.1,
    "TopP": 1.0,
    "MaxPromptTokens": null,
    "MaxCompletionTokens": null,
    "TruncationStrategy": {
      "Type": {},
      "LastMessages": null
    },
    "ToolChoice": {
      "Length": 6,
      "IsEmpty": false,
      "MediaType": null
    },
    "ResponseFormat": {
      "Length": 6,
      "IsEmpty": false,
      "MediaType": null
    },
    "Metadata": {},
    "ToolResources": {
      "CodeInterpreter": {
        "FileIds": [],
        "DataSources": []
      },
      "FileSearch": null,
      "AzureAISearch": null,
      "Mcp": []
    },
    "ParallelToolCalls": true
  },
  "UpdateKind": 2
} => 
2025-07-18 11:40:20.7342|DEBUG|Streaming update received: RunQueued - Raw: {
  "Value": {
    "RequiredActions": [],
    "Id": "...",
    "ThreadId": "...",
    "AssistantId": "...",
    "Status": {},
    "RequiredAction": null,
    "LastError": null,
    "Model": "gpt-4.1",
    "Instructions": "..."
    "Tools": [
      {
        "ServerLabel": "WorkMCPTools",
        "ServerUrl": "..."
        "AllowedTools": []
      },
      {
        "ConnectedAgent": {
          "Id": "...",
          "Name": "...",
          "Description": "..."
        }
      },
      {}
    ],
    "CreatedAt": "2025-07-18T09:40:18+00:00",
    "ExpiresAt": "2025-07-18T10:10:18+00:00",
    "StartedAt": null,
    "CompletedAt": null,
    "CancelledAt": null,
    "FailedAt": null,
    "IncompleteDetails": null,
    "Usage": null,
    "Temperature": 0.1,
    "TopP": 1.0,
    "MaxPromptTokens": null,
    "MaxCompletionTokens": null,
    "TruncationStrategy": {
      "Type": {},
      "LastMessages": null
    },
    "ToolChoice": {
      "Length": 6,
      "IsEmpty": false,
      "MediaType": null
    },
    "ResponseFormat": {
      "Length": 6,
      "IsEmpty": false,
      "MediaType": null
    },
    "Metadata": {},
    "ToolResources": {
      "CodeInterpreter": {
        "FileIds": [],
        "DataSources": []
      },
      "FileSearch": null,
      "AzureAISearch": null,
      "Mcp": []
    },
    "ParallelToolCalls": true
  },
  "UpdateKind": 3
} => 
2025-07-18 11:40:21.3331|DEBUG|Streaming update received: RunInProgress - Raw: {
  "Value": {
    "RequiredActions": [],
    "Id": "...",
    "ThreadId": "...",
    "AssistantId": "...",
    "Status": {},
    "RequiredAction": null,
    "LastError": null,
    "Model": "gpt-4.1",
    "Instructions": "...",
    "Tools": [
      {
        "ServerLabel": "WorkMCPTools",
        "ServerUrl": "...",
        "AllowedTools": []
      },
      {
        "ConnectedAgent": {
          "Id": "...",
          "Name": "...",
          "Description": "..."
        }
      },
      {}
    ],
    "CreatedAt": "2025-07-18T09:40:18+00:00",
    "ExpiresAt": "2025-07-18T10:10:18+00:00",
    "StartedAt": "2025-07-18T09:40:19+00:00",
    "CompletedAt": null,
    "CancelledAt": null,
    "FailedAt": null,
    "IncompleteDetails": null,
    "Usage": null,
    "Temperature": 0.1,
    "TopP": 1.0,
    "MaxPromptTokens": null,
    "MaxCompletionTokens": null,
    "TruncationStrategy": {
      "Type": {},
      "LastMessages": null
    },
    "ToolChoice": {
      "Length": 6,
      "IsEmpty": false,
      "MediaType": null
    },
    "ResponseFormat": {
      "Length": 6,
      "IsEmpty": false,
      "MediaType": null
    },
    "Metadata": {},
    "ToolResources": {
      "CodeInterpreter": {
        "FileIds": [],
        "DataSources": []
      },
      "FileSearch": null,
      "AzureAISearch": null,
      "Mcp": []
    },
    "ParallelToolCalls": true
  },
  "UpdateKind": 4
} => 
2025-07-18 11:40:24.0755|DEBUG|Streaming update received: RunStepCreated - Raw: {
  "Value": {
    "Id": "step_vCdfZlqg7OH1pwzUHWqUhcxN",
    "Type": {},
    "AssistantId": "...",
    "ThreadId": "...",
    "RunId": "...",
    "Status": {},
    "StepDetails": {
      "ToolCalls": []
    },
    "LastError": null,
    "CreatedAt": "2025-07-18T09:40:22+00:00",
    "ExpiredAt": null,
    "CompletedAt": null,
    "CancelledAt": null,
    "FailedAt": null,
    "Usage": null,
    "Metadata": null
  },
  "UpdateKind": 12
} => 
2025-07-18 11:40:27.7618|DEBUG|Streaming update received: RunStepInProgress - Raw: {
  "Value": {
    "Id": "step_vCdfZlqg7OH1pwzUHWqUhcxN",
    "Type": {},
    "AssistantId": "...",
    "ThreadId": "...",
    "RunId": "...",
    "Status": {},
    "StepDetails": {
      "ToolCalls": []
    },
    "LastError": null,
    "CreatedAt": "2025-07-18T09:40:22+00:00",
    "ExpiredAt": null,
    "CompletedAt": null,
    "CancelledAt": null,
    "FailedAt": null,
    "Usage": null,
    "Metadata": null
  },
  "UpdateKind": 13
} => 
2025-07-18 11:40:27.8206|DEBUG|Streaming update received: RunStepUpdated - Raw: {
  "StepId": "step_vCdfZlqg7OH1pwzUHWqUhcxN",
  "CreatedMessageId": null,
  "ToolCallId": null,
  "ToolCallIndex": null,
  "CodeInterpreterInput": null,
  "CodeInterpreterOutputs": null,
  "FunctionArguments": null,
  "FunctionOutput": null,
  "UpdateKind": 14
} => 
2025-07-18 11:40:27.8459|DEBUG|Streaming update received: RunStepUpdated - Raw: {
  "StepId": "step_vCdfZlqg7OH1pwzUHWqUhcxN",
  "CreatedMessageId": null,
  "ToolCallId": null,
  "ToolCallIndex": null,
  "CodeInterpreterInput": null,
  "CodeInterpreterOutputs": null,
  "FunctionArguments": null,
  "FunctionOutput": null,
  "UpdateKind": 14
} => 
2025-07-18 11:40:27.8606|DEBUG|Streaming update received: RunStepUpdated - Raw: {
  "StepId": "step_vCdfZlqg7OH1pwzUHWqUhcxN",
  "CreatedMessageId": null,
  "ToolCallId": null,
  "ToolCallIndex": null,
  "CodeInterpreterInput": null,
  "CodeInterpreterOutputs": null,
  "FunctionArguments": null,
  "FunctionOutput": null,
  "UpdateKind": 14
} => 
2025-07-18 11:40:27.8754|DEBUG|Streaming update received: RunStepUpdated - Raw: {
  "StepId": "step_vCdfZlqg7OH1pwzUHWqUhcxN",
  "CreatedMessageId": null,
  "ToolCallId": null,
  "ToolCallIndex": null,
  "CodeInterpreterInput": null,
  "CodeInterpreterOutputs": null,
  "FunctionArguments": null,
  "FunctionOutput": null,
  "UpdateKind": 14
} => 
2025-07-18 11:40:27.8890|DEBUG|Streaming update received: RunStepUpdated - Raw: {
  "StepId": "step_vCdfZlqg7OH1pwzUHWqUhcxN",
  "CreatedMessageId": null,
  "ToolCallId": null,
  "ToolCallIndex": null,
  "CodeInterpreterInput": null,
  "CodeInterpreterOutputs": null,
  "FunctionArguments": null,
  "FunctionOutput": null,
  "UpdateKind": 14
} => 
2025-07-18 11:40:27.9035|DEBUG|Streaming update received: RunStepUpdated - Raw: {
  "StepId": "step_vCdfZlqg7OH1pwzUHWqUhcxN",
  "CreatedMessageId": null,
  "ToolCallId": null,
  "ToolCallIndex": null,
  "CodeInterpreterInput": null,
  "CodeInterpreterOutputs": null,
  "FunctionArguments": null,
  "FunctionOutput": null,
  "UpdateKind": 14
} => 
2025-07-18 11:40:27.9180|DEBUG|Streaming update received: RunStepUpdated - Raw: {
  "StepId": "step_vCdfZlqg7OH1pwzUHWqUhcxN",
  "CreatedMessageId": null,
  "ToolCallId": null,
  "ToolCallIndex": null,
  "CodeInterpreterInput": null,
  "CodeInterpreterOutputs": null,
  "FunctionArguments": null,
  "FunctionOutput": null,
  "UpdateKind": 14
} => 
2025-07-18 11:40:29.3118|INFO|QueryWorkDetails completed - SessionId: ..., Full Response:  =>

After last one the stream is completed with no output.

marianosz Jul 28, 2025
Author

Hello team, just an update, the issue is still present from C# code and Agent Playground.

Tested also hitting the MCP server from copilot agent and is working fine, like hitting from API REST requests.

amynic Aug 4, 2025
Maintainer

Hi @marianosz please submit a bug in the agent playground (smiley face top right corner) in order to make sure this experience is reviewed

Azure AI Foundry

Model Context Protocol Support in Azure AI Foundry Agent Service is not working #93

Uh oh!

marianosz Jul 8, 2025

Technical Feedback

Desired Outcome

Current Workaround

Replies: 4 comments · 13 replies

Uh oh!

marianosz Jul 9, 2025 Author

Uh oh!

Uh oh!

gloveboxes Jul 11, 2025

Uh oh!

gloveboxes Jul 12, 2025

Uh oh!

amynic Jul 14, 2025 Maintainer

Uh oh!

marianosz Jul 14, 2025 Author

Uh oh!

elbruno Jul 14, 2025

Uh oh!

marianosz Jul 15, 2025 Author

Uh oh!

gloveboxes Jul 13, 2025

Uh oh!

Uh oh!

marianosz Jul 13, 2025 Author

Uh oh!

Uh oh!

gloveboxes Jul 18, 2025

Uh oh!

marianosz Jul 18, 2025 Author

Uh oh!

Uh oh!

marianosz Jul 28, 2025 Author

Uh oh!

amynic Aug 4, 2025 Maintainer

marianosz
Jul 8, 2025

Replies: 4 comments 13 replies

marianosz
Jul 9, 2025
Author

gloveboxes
Jul 11, 2025

amynic Jul 14, 2025
Maintainer

marianosz Jul 14, 2025
Author

marianosz Jul 15, 2025
Author

gloveboxes
Jul 13, 2025

marianosz Jul 13, 2025
Author

gloveboxes
Jul 18, 2025

marianosz Jul 18, 2025
Author

marianosz Jul 28, 2025
Author

amynic Aug 4, 2025
Maintainer