Claude Code Billing Bug Triggered by Specific String

A bug has been reported in Anthropic's developer tool Claude Code, where having a git commit history containing a specific string results in extra usage charges based on API rates instead of the existing subscription plan.

Details:

• Cause: Occurs when the uppercase string "HERMES.md" is included in a git commit message.
• How it works: When Claude Code includes recent commit history in the system prompt and recognizes this string, it ignores the user's Max plan usage and routes to API-based extra usage instead.
• Impact: Users suddenly receive a request for additional payment, even though their subscription plan still has sufficient remaining capacity.

This issue was reproduced by a user, and Anthropic has confirmed it as a bug. Developers using Claude Code should be careful not to include this string in their commit messages.