Jboudreau/support gpt image models

[joe-boudreau]

Q	A
Bug fix?	yes
New feature?	yes
BC breaks?	no

Describe your change

• Update the ImagesApi with 4 new methods:
  • imageCreate
  • imageEdit
  • imageCreateFlow
  • imageEditFlow

These are meant to replace the imageURL and imageJson methods in this interface once the Dall-E models are deprecated and removed in May 2026. I elected to leave them in for now to make this a backwards compatible library update. A future library update ( after May 2026) should remove these methods and simplify the API.

The OpenAI Images API only supports base_64 encoded JSON images now, the external URL option will be gone once the Dall-E models are deprecated. So the new interface methods represent that future state.

What problem is this fixing?

Dall-E Deprecation

In May 2026, OpenAI will be removing the Dall-E Image models from their API:
https://platform.openai.com/docs/deprecations#2025-11-14-dall-e-model-snapshots
These models will be unavailable after that.
In addition, the image variation endpoint is only supported by dall-e-2: https://platform.openai.com/docs/api-reference/images/createVariation
So presumably it will also be removed when the models are removed.

GPT Image support

The new class of image models (gpt-image-*) aren't supported by the Image interface in this library currently because it doesn't allow NOT setting the response_format field in the request. Requests with this field are rejected by OpenAI because that field is only supported by the Dall-E models:

Caused by: io.ktor.client.plugins.ClientRequestException: Client request(POST https://api.openai.com/v1/images/generations) invalid: 400 Bad Request. Text: "{
"error": {
"message": "Unknown parameter: 'response_format'.",
"type": "invalid_request_error",
"param": "response_format",
"code": "unknown_parameter"
}
}"

So the updates to the Image interface make this an optional field so you can actually use the GPT Image models now.

https://platform.openai.com/docs/api-reference/images

[joe-boudreau]

these tests were failing now because the OpenAI API doesn't support application/octet-stream as a valid content type anymore. it needs to be image/png

[joe-boudreau]

@aallam can you please review this - it's ready to be merged if you agree with the changes