[BUG] `claude update` downloads full binary even when already up to date

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?

(I have a slow internet connection so the bug is very noticeable. Would not be the case with fast internet)

claude update takes ~2 minutes even when already on the latest version. Activity Monitor shows constant download activity at max bandwidth during the entire check, suggesting the full binary is being downloaded just to determine the version.

The expected flow should be:

1. Fetch latest version string (small request)
2. Compare to local version
3. Only download binary if versions differ

Current behavior appears to download the full binary regardless, then report "up to date."

Diagnostic Info

# npm version check is fast (~1.5s)
$ time npm view @anthropic-ai/claude-code version
2.1.15
Executed in  1.52 secs

# Direct registry request is fast (~1.7s)
$ curl -w "%{time_total}\n" -o /dev/null -s https://registry.npmjs.org/@anthropic-ai/claude-code
1.701204

# But claude update takes ~2 minutes with constant download activity
$ claude update
Current version: 2.1.15
Checking for updates to latest version...
Claude Code is up to date (2.1.15)

What Should Happen?

Version check should complete in seconds by comparing version strings before deciding to download. The full binary should only be downloaded when an update is actually needed.

Claude Code Version

2.1.15

Operating System

macOS

Additional Information

This is particularly problematic on slow or metered connections.

What Should Happen?

The version is compared, no need to re-download the same version when already up to date.

Error Messages/Logs

Steps to Reproduce

Steps to Reproduce

1. Ensure you're on the latest version
2. Run claude update
3. Observe download activity in Activity Monitor / network monitor
4. Wait ~2 minutes for "up to date" message

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.15

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_