Flux-pro-1.1 throws bad request (even in playground) "Model not supported with Responses API."

Question

Flux-pro-1.1 throws bad request (even in playground) "Model not supported with Responses API."

Jona 0

Suddenly our flux-pro-1.1 deployment stopped working again.

We get this error:

"``Model not supported with Responses API."

This occurs not just in our code but even when I use the playground:

2026-09-02_10-15

As of now our deployment is not working at all and our client product is broken.

Steps to reproduce:

Open the FLUX-1.1-pro deployment.
Open the playground.
Enter the following sanitized prompt:
Select Generate.
The error appears.

What can we do?

Jona 0 Reputation points

2026-09-02T13:11:00.5766667+00:00
@Ganesh Gurram thanks for your answer.

I am calling it like this

import { AzureOpenAI } from "openai"; new AzureOpenAI({ endpoint, apiKey, apiVersion, deployment: deploymentName, }) .images.generate({ prompt, n, size, });

and I did not change this code at all. This worked for months. And just now suddenly it stopped working without any warning. So I checked the deployment in the dashboard and everything seemed fine which led me to try the playground which gave me the same error. It really seems like there have been changes on MS ends.

It seems like it gets wrongly routed internally through the responses API.
Ganesh Gurram 7,405 Reputation points Microsoft External Staff Moderator

2026-09-03T00:49:35.3566667+00:00

@Jona - We have reached out to you via private message requesting some additional details. Could you please share the requested information? These details will help us investigate the issue further.

Additionally, please confirm whether the issue impacts only this specific FLUX deployment or all FLUX deployments within the resource.

This information will help us investigate further and determine whether there is a service-side issue affecting the deployment or Playground experience.

Thank you.

1 answer

Your answer

Jona 0 Reputation points

2026-09-02T13:11:00.5766667+00:00

@Ganesh Gurram thanks for your answer.

I am calling it like this

import { AzureOpenAI } from "openai"; new AzureOpenAI({ endpoint, apiKey, apiVersion, deployment: deploymentName, }) .images.generate({ prompt, n, size, });

and I did not change this code at all. This worked for months. And just now suddenly it stopped working without any warning. So I checked the deployment in the dashboard and everything seemed fine which led me to try the playground which gave me the same error. It really seems like there have been changes on MS ends.

It seems like it gets wrongly routed internally through the responses API.
Ganesh Gurram 7,405 Reputation points Microsoft External Staff Moderator

2026-09-03T00:49:35.3566667+00:00

@Jona - We have reached out to you via private message requesting some additional details. Could you please share the requested information? These details will help us investigate the issue further.

Additionally, please confirm whether the issue impacts only this specific FLUX deployment or all FLUX deployments within the resource.

This information will help us investigate further and determine whether there is a service-side issue affecting the deployment or Playground experience.

Thank you.

Answer 1

Hi @Jona

Thank you for posting your query in MS Q&A forum.

Based on the error message shown in the Playground:

Model not supported with Responses API.

the request appears to be going through a Responses API-based flow. FLUX-1.1-pro is an image-generation model, and the current Microsoft Foundry documentation lists it as supported through the Image API (images/generations) and the Black Forest Labs (BFL) provider-specific API.

Therefore, this error does not by itself indicate that the FLUX deployment is corrupted or needs to be recreated.

Please verify the API path being used:

For FLUX-1.1-pro, please verify that the application is using one of the supported interfaces:

Image API (images/generations)
BFL provider-specific API for flux-pro-1.1

The current documentation provides the Image API endpoint for FLUX-1.1-pro and the corresponding BFL provider endpoint.

If the application is explicitly calling the Responses API with the FLUX-1.1-pro deployment, please switch to the Image API or BFL API instead.

Since the Playground is also affected:

Because you are seeing the same error directly in the Foundry Playground, this is useful information and may indicate an issue with how the Playground is routing the request rather than an issue with your application code.

If the Playground previously worked with this deployment and no deployment or application changes were made, please share more details in private message. This will help us investigate further.

If possible, please also test the same deployment using the Image API (images/generations). If the Image API succeeds while the Playground continues to return "Model not supported with Responses API", that would help isolate the issue to the Playground/API routing path.

For more details refer: Deploy and use FLUX models in Microsoft Foundry

Foundry Models sold by Azure

I Hope this helps. Do let me know if you have any further queries.

If this answers your query, please do click Accept Answer and Yes for was this answer helpful.