API receives wrong client version (2.1.133) despite running 2.1.296 — blocks model selection

Bug Description

When selecting a model via /model claude-opus-5-5, the API rejects the request claiming the client version is 2.1.133, even though the installed version is 2.1.296.

Error message:

API error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"Claude Code 2.1.133 does not support this model; version 2.1.280 or newer is required. Run 'claude update', or update the Claude desktop app, then try again.","details":{"error_code":"claude_code_version_too_old"}}}

Expected Behavior

The API should receive version 2.1.296 as the client version, and the model selection should succeed since 2.1.296 > 2.1.280.

Actual Behavior

The API receives 2.1.133 as the client version and rejects the request.

Version Confirmation

$ claude --version
2.1.296 (Claude Code)

$ which claude
/Users/<user>/.local/bin/claude

$ ls -la /Users/<user>/.local/bin/claude
lrwxr-xr-x claude -> /Users/<user>/.local/share/claude/versions/2.1.296

Possible Clue

Old version binaries are still present in the versions directory:

$ ls /Users/<user>/.local/share/claude/versions/
2.1.123
2.1.132
2.1.133    <-- the version the API erroneously reports
2.1.296    <-- the actual current version (symlinked)

The binary contains the string anthropic-client-version (likely the header used to report client version to the API). It's possible the version sent in this header is incorrect, or there's a lookup/resolution issue with old version files present.

Environment

• Platform: macOS (Darwin 25.3.0, arm64)
• Claude Code version: 2.1.296
• Installation method: Binary in ~/.local/share/claude/versions/
• Shell: zsh