Based on what I've read it appears the problem showed up with the 'heat fix' for iPhone 15 devices which was 17.0.3. Rolling back to a version before that and preventing your device from doing an auto update should resolve your problem. Testing my assumptions now with Xcode RC 15.0.1.

I was able to get this working on Mac OS 13.6 using "Xcode Version 15.1 beta (15C5028h)"

With the 17.1 release of the SDK all of the issues went away for me.

I'm not able to get Metal to download on Xcode Beta 5 from macOS 26 Beta 5. Not sure how you pulled that off. 🤷‍♂️

It does NOT get fixed by re-launching Xcode 26 - beta 5. It doesn't even get fixed if I deleted what was installed, re-download the xip file and re-install. On the Settings screen the 'Other Components' section, clicking on the Get button does zilch. No download, nothing happens. Please explain to me how relaunching the Xcode instance fixed the endPoint that contains the Metal Toolchain that can't be found? Thanks.

It's not resolved. I've restarted systems. I've tried form Mac OS 26 beta 5 boxes and it isn't working.

This issue has NOT been fixed. How can Apple say it's fixed without confirmation by folks posting the problem?

Still see this: xcodebuild -downloadComponent MetalToolchain Beginning asset download... 2025-08-08 08:35:42.815 xcodebuild[40572:570166] Writing error result bundle to /var/folders/zy/pzh3hh415f5d7t09yj61qm580000gp/T/ResultBundle_2025-08-08_08-35-0042.xcresult xcodebuild: error: Failed fetching catalog for assetType (com.apple.MobileAsset.MetalToolchain), serverParameters ({ RequestedBuild = 17A5295f; })