For those using mise install claude installed by a previous mise version

[Max-Cheng]

If you installed claude (claude-code) via mise in an earlier version and are now running into the following error when trying to upgrade:

$ mise up claude --verbose
...
DEBUG backend for 'claude' changed from stored 'http:claude' to registry 'aqua:anthropics/claude-code'
DEBUG backend for 'claude' changed from stored 'http:claude' to registry 'aqua:anthropics/claude-code'
...
Error:
   0: Failed to install aqua:anthropics/claude-code@latest: Http backend requires 'url' option

Location:
   src/toolset/toolset_install.rs:230

Version:
   2026.3.9 macos-arm64 (2026-03-13)

Root Cause

The claude tool's backend in the mise registry has changed from http:claude to aqua:anthropics/claude-code. However, the locally cached backend type from your previous installation still points to the old http backend, which requires a url option that no longer exists in this context — causing the install to fail.

Fix

Simply clear the mise cache and re-run the upgrade:

mise cache clear
mise up claude

This forces mise to discard the stale backend metadata and resolve claude correctly via the new aqua backend.

Hope this saves someone a headache! 🙌

[nemanjaglumac]

Didn't work for me.
The only thing that worked was:

mise uninstall claude
mise install