fix(openai): handle image-url tool result content type in responses API

[MarcACard]

Background

The AI SDK defines image-url as a valid tool result content type in LanguageModelV3ToolResultOutput, but the OpenAI provider's convertToOpenAIResponsesInput function didn't handle this type.

When a tool returned image-url content, it fell through to the default case, produced a warning ("unsupported tool content part type: image-url"), and the image was dropped.

Summary

Added a case to handle image-url tool result content by converting it to OpenAI's input_image format. OpenAI's Responses API accepts HTTP URLs in the image_url field (alongside data URLs), so this is a gap in the provider implementation rather than a missing API feature.

Manual Verification

I tested these changes in a separate project with a tool that returns image-url content:

• Before fix: Warning displayed ("unsupported tool content part type: image-url") and image was dropped
• After fix: No warning, and the LLM successfully processed and described the image from the URL

I can provide a self-contained code sample if needed.

Checklist

• Tests have been added / updated (for bug fixes / features)
• Documentation has been added / updated (for bug fixes / features)
• A patch changeset for relevant packages has been added (for bug fixes / features - run pnpm changeset in the project root)
• I have reviewed this pull request (self-review)

[aayush-kapoor]

hi thanks for the PR!

I can provide a self-contained code sample if needed.

yes please - add it in the examples folder in the appropriate sub directory so that we can verify it too

[aayush-kapoor]

can you take a look at the failing CI tests?
nevermind, i fixed them

[MarcACard]

yes please - add it in the examples folder in the appropriate sub directory so that we can verify it too

Sure thing, will pull something together and update.

[MarcACard]

Example added for testing 👍

[aayush-kapoor]

verified that the fix works for the example