Claude Code doesn't work - unknown variant `rate_limit_event`

[wadamek65]

Version

0.19.3

Operating System

Windows

Distribution Method

msi (Windows)

Describe the issue

Connection is okay in the settings, but when trying to run claude it seems to start up just fine but after the first message it always errors out. It enters plan mode and then the error appears. Not sure what could be the case.

SDK error: Message parse error: Message parse error: Failed to parse message: unknown variant `rate_limit_event`, expected one of `assistant`, `system`, `result`, `stream_event`, `user`, `control_cancel_request`

How to reproduce (Optional)

No response

Expected behavior (Optional)

No response

Relevant log output (Optional)

[Byron]

Thanks a lot for reporting!

I tracked this issue down to:

gitbutler/crates/but-claude/src/session.rs

Line 609 in d2fb905

message: format!("SDK error: {e}"),

It boils down to a shortcoming in the Claude SDK which we forked to add tool-use support.
It's not very active, and it doesn't look like that bug was fixed there either:

2026-02-09 13:20 -0800 Tyr Chen         o {origin/HEAD} {origin/master} Update CHANGELOG.md
2026-02-09 13:19 -0800 Tyr Chen         o <v0.6.4> chore: bump version to 0.6.4
2026-02-09 13:19 -0800 Paul-Louis Pröve o Fix: Hide console window on Windows (CREATE_NO_WINDOW) (#19)
2026-01-30 09:03 +0100 Mattias Granlund │ o [tool-use] {fork/can-use-tool} feat: Add tool permission callback support for CLI integration
2026-01-26 07:46 -0800 Tyr Chen         o─┘ [master] {fork/HEAD} {fork/master} refactor: Improve code quality with DRY/SOLID principles and add tests (#16)
2026-01-25 18:46 -0800 Tyr Chen         o feat(testing): Add comprehensive testing mock framework (#11815 

Maybe another bugfix is needed in our fork? CC @mtsgrd

[mtsgrd]

I've got an update coming, just using it in dev for a bit before I put up the pr.

[mtsgrd]

Landed today a fix today here: #12558

[wadamek65]

Can confirm it works for me now!

@mtsgrd Thank you!