[BUG] Image upload returns 500 error in Claude Code web interface (iPad)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Uploading images via the “+” button in the Claude Code web interface consistently returns a 500 error. This happens when selecting screenshots from the iPad photo library (iPad Pro, Safari).
Steps to reproduce:

1. Open a Claude Code web session
2. Tap the “+” button to attach an image
3. Select a screenshot from the photo library
4. Send the message

Expected: Image is received and displayed in the conversation.
Actual: 500 error is returned. The session does not recover — subsequent attempts also fail until a new session is started.
Environment:
∙ Device: iPad Pro
∙ Browser: Safari
∙ Claude Code web interface

What Should Happen?

The image should be rendered inline in the conversation so Claude can view and analyze it. Previously, image uploads worked — Claude could read screenshots and provide feedback on UI elements, errors, and visual content. The expected behavior is that Claude receives the image and responds to it as part of the conversation.

Error Messages/Logs

API Error: 400 {“type”:“error”,“error”:{“type”:“invalid_request_error”,“message”:“messages.54.content.1.image.source.base64.media_type: Field required”},“request_id”:“req_011CY3PyHsUPVcohtgZ21hnZ”}

Steps to Reproduce

!Image

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

not sure

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_