[BUG] API Error: Rate limit reached on first message despite Claude Pro subscription and zero prior usage

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 v2.1.76
macOS, Apple Silicon
Login method: Claude Pro Account
Rate limit error appears on the very first message in a fresh session
/status confirms Pro subscription is active
No ANTHROPIC_API_KEY environment variable set
Persists after /logout + /login
Persists after removing duplicate npm install at /usr/local/bin/claude
No incidents on status.claude.com
Have not used Claude Code in 24+ hours prior to errors

What Should Happen?

Claude Code should respond normally to messages when authenticated with an active Claude Pro subscription and no prior usage in the past 24+ hours. The rate limit error should not appear until actual usage limits have been reached.

Error Messages/Logs

API Error: Rate limit reached

Steps to Reproduce

Active Claude Pro subscription on claude.ai
Claude Code v2.1.76 installed via npm at ~/.local/bin/claude
No ANTHROPIC_API_KEY environment variable set (echo $ANTHROPIC_API_KEY returns blank)
Run claude in Terminal
/status confirms: Login method: Claude Pro Account, model: claude-sonnet-4-6[1m]
Type any message (e.g. "hi")
Immediately receive: API Error: Rate limit reached

Expected: Normal response
Actual: Rate limit error on first message with zero prior usage in 24+ hours
Things already tried:

/logout then /login
Confirmed no duplicate install (removed /usr/local/bin/claude)
Confirmed no active Anthropic outages
Confirmed no API key in environment

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

v2.1.76

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_