[BUG] False update notification on v2.1.2 installed via Homebrew (macOS)

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?

Claude Code CLI v2.1.2 continuously displays an "Update available! Run: brew upgrade claude-code" message, even though this is already the latest version available.

What Should Happen?

The update notification should not appear when running the latest available version.

Error Messages/Logs

Steps to Reproduce

Environment

Claude Code Version: 2.1.2 (verified with claude --version)
Installation Method: Homebrew on macOS
System: macOS (Apple Silicon M4)
Shell: zsh

Steps to Reproduce

Install claude-code via Homebrew: brew install claude-code
Verify latest version is installed: brew info claude-code shows 2.1.2
Run claude command
Observe persistent "Update available!" message in the footer

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.2 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Attempted Solutions
All of the following have been attempted without resolving the issue:

brew update && brew upgrade claude-code - Homebrew reports already on latest version
brew reinstall claude-code - Issue persists
brew uninstall claude-code && brew install claude-code - Clean reinstall, issue persists
Cleared all cache directories in ~/.claude/ including:

cache/
stats-cache.json
shell-snapshots/
debug/

Verified no conflicting environment variables: env | grep -i claude shows nothing

Additional Notes

The CLI functions normally otherwise
Homebrew formula appears to be up-to-date
This seems to be a version detection bug in the CLI itself