Missing method when calling GetResponsesClient() on AzureOpenAIClient

[hansmbakker]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

sp.GetRequiredService<AzureOpenAIClient>().GetResponsesClient();

results in

Unhandled exception. System.MissingMethodException: Method not found: 'Void OpenAI.Responses.ResponsesClient..ctor(System.ClientModel.Primitives.ClientPipeline, OpenAI.OpenAIClientOptions)'.
   at Azure.AI.OpenAI.Responses.AzureResponsesClient..ctor(ClientPipeline pipeline, String deploymentName, Uri endpoint, AzureOpenAIClientOptions options)
   at Azure.AI.OpenAI.AzureOpenAIClient.GetResponsesClient()

Expected Behavior

No response

Steps To Reproduce

Create an agent service using the following packages:

    <PackageReference Include="Aspire.Azure.AI.OpenAI" />
    <PackageReference Include="Microsoft.Agents.AI.A2A" />
    <PackageReference Include="Microsoft.Agents.AI.Harness" />
    <PackageReference Include="Microsoft.Agents.AI.Hosting.AGUI.AspNetCore" />
    <PackageReference Include="Microsoft.Agents.AI.Hosting.AspNetCore" />
    <PackageReference Include="Microsoft.Agents.AI.Hosting.OpenAI" />
    <PackageReference Include="Microsoft.Agents.AI.Workflows" />
    <PackageReference Include="Microsoft.Agents.AI.Workflows.Generators" PrivateAssets="all" />
    <PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" />
    <PackageReference Include="Microsoft.Identity.Web" />

Exceptions (if any)

Unhandled exception. System.MissingMethodException: Method not found: 'Void OpenAI.Responses.ResponsesClient..ctor(System.ClientModel.Primitives.ClientPipeline, OpenAI.OpenAIClientOptions)'.
   at Azure.AI.OpenAI.Responses.AzureResponsesClient..ctor(ClientPipeline pipeline, String deploymentName, Uri endpoint, AzureOpenAIClientOptions options)
   at Azure.AI.OpenAI.AzureOpenAIClient.GetResponsesClient()

Aspire doctor output

Anything else?

It might be an issue that is caused by the following differences in dependency versions:

Microsoft.Agents.AI.Hosting.OpenAI 1.21.0-alpha.260911.1:

• OpenAI (>= 2.13.0)

Aspire.Azure.AI.OpenAI 13.5.4-preview.1.26464.4:

• Azure.AI.OpenAI (>= 2.9.0-beta.1)
• OpenAI (>= 2.12.0)

Also reported as microsoft/agent-framework#7484

Seemingly related to Azure/azure-sdk-for-net#60689

Workaround not possible: It might have been possible to work around this when manually specifying the OpenAI package version but that is blocked by the

Aspire.Azure.AI.OpenAI 13.5.4-preview.1.26464.4 -> OpenAI (>= 2.12.0)

requirement

[joperezr]

🤖 Aspire triage pass — 2026-09-16 13:21 UTC

Area: area-integrations
Kind: bug
Repro: partial — see lines 7–16 and 30–35 of the issue body
Affected version(s): 13.5.4-preview.1 (latest: 13.5.4)
Severity: S3 — a specific Azure OpenAI and Agents package combination fails at runtime; the report identifies a likely dependency conflict but lacks a standalone repro

Urgency: ⚪ backlog — no milestone
Reason: credible integration compatibility issue, but the preview-version report and partial repro are not sufficient to plan it into 13.6

Suggested owner(s): Sébastien Ros (@sebastienros) (score 141), backup Eric Erhardt (@eerhardt) (score 81)
Evidence:

• sebastienros merged Add polyglot Azure provisioning proxy SDKs #19675, Fix Python callback handle wrapping #19870, [release/13.5] Mark Radius provider builders experimental #19874, [release/13.5] Pin C# API surface #19866, [release/13.5] Pin Polyglot API surface #19864 in area-integrations (last 30d)
• sebastienros closed aspire destroy fails to uninstall Helm release for AKS deployments #19206 and Polyglot-Compatible Integration Discovery #15320 as completed in area-integrations
• eerhardt merged Remove InternalsVisibleTo from Aspire.Hosting to Aspire.Hosting.Radius #20143, Add missing hosting project READMEs #20120, Pass execution context to Bicep parameter value providers #20012, Derive Azure Front Door origin names from backend hostnames #20035, Allow skipping main.bicep generation in AzurePublishingContext #19914 in area-integrations (last 30d)
• eerhardt closed Remove Github Model resources #18953 and Hide azure-environment when all Azure resources use emulators #19617 as completed in area-integrations

Confidence: medium
Needs human?: no

[hansmbakker]

I got feedback that Azure.AI.OpenAI is not supported anymore:

The Azure.AI.OpenAI is not actively supported anymore, please switch using Azure.AI.Projects or Azure.AI.Extensions.OpenAI.

Could you please see what this means for the (Azure) OpenAI Aspire component and the advice on what package to use, to get a Responses client for a model in Foundry?

The other Aspire component (Aspire.Azure.AI.Inference), recommended for connecting to Foundry, uses a retired SDK:

Azure AI Inference beta SDK retired on August 26, 2026. Switch to the generally available OpenAI/v1 API with a stable OpenAI SDK. Follow the migration guide to switch to OpenAI/v1, using the SDK for your preferred programming language.

See #18525 and microsoft/aspire.dev#1658