HN zeroed in on the weirdest Claude Code billing bug yet: HERMES.md in commit history

Hacker News jumped on this one because the trigger sounded almost too ridiculous to be real. In a GitHub issue that later spilled into a large HN thread, a Claude Code user showed that having the exact uppercase string HERMES.md in recent git commit messages could route requests to paid extra-usage billing instead of the included Max plan quota. That is the kind of bug developers instantly pass around, because it collapses the normal boundary between harmless repo metadata and money leaving your account.

The reproduction described in the issue is unusually clean. The reporter said an empty repo with a commit message like add HERMES.md failed, while lowercase hermes.md, HERMES without the extension, or an actual file on disk without the commit text did not trigger the behavior. The issue claimed $200.98 in extra charges while the Max 20x plan dashboard still showed most of the weekly allowance untouched. In other words, the scary part was not simply a bad error message. The scary part was that two near-identical requests could be billed through different paths for reasons the user could not see.

Anthropic engineer bcherny replied on the issue that the behavior came from an overactive anti-abuse system and was fixed. But that did not settle the discussion, because attention quickly shifted from the bug itself to the support response around it. HN users were especially angry after the reporter shared a reply saying compensation could not be issued for technical errors that caused incorrect billing routing. A few hours later, Thariq from the Claude Code team posted on HN that everyone affected would receive a full refund plus an extra grant of usage credits equal to the monthly subscription.

That sequence is why the story kept running even after the bug was closed. Community discussion noted that hidden prompt or repo context influencing billing feels worse than an ordinary quota outage, because users have almost no way to reason about it from the outside. Several commenters also focused on how slowly the support flow escalated a case that mixed infrastructure behavior, pricing, and trust. The final refund update cooled the temperature, but the thread still landed as a warning: if internal routing rules can silently reinterpret context and change what counts against your plan, billing transparency is no longer a side issue for coding agents.