Case-sensitive string HERMES.md in git commit messages silently routes Claude Code API requests to extra usage billing, bypassing Max plan quota.
Key Takeaways
Claude Code injects recent commit history into the system prompt; server-side logic triggers on HERMES.md (exact case) and re-routes to extra usage billing.
Trigger is the string in commit messages only – not a file named HERMES.md on disk, not lowercase hermes.md, not HERMES or HERMES.txt.
Reporter lost $200.98 in extra usage credits while Max 20x plan ($200/month) showed 86%+ weekly capacity remaining; error message gave no indication of cause.
Orphan branch (no commit history) routes normally; minimal repro requires only git commit -m "add HERMES.md" with no other project files.
Diagnosis required binary search across commit history; the bug is invisible until extra usage credits are exhausted.
Hacker News Comment Review
Initial Anthropic support response explicitly refused compensation for technical errors in billing routing, which drew widespread criticism as an unprecedented and unacceptable policy position.
Thariq from the Claude Code team later confirmed full refunds plus an extra usage grant equal to the monthly subscription for all affected users, contradicting the support response.
Commenters noted a pattern of Anthropic taking hard-line positions then reversing under public pressure, pointing to internal communication failures between support and engineering.
Notable Comments
@trq_: Confirmed full refund plus bonus credit equal to monthly subscription for all affected users; noted support flow was not set up to escalate complex billing bugs to engineering.
@ecshafer: “I’ve never seen a legitimate business not give refunds for technical errors of their own fault.”
