Forgotten /loop command checking PRs every 30 minutes ran 46 times over 26 hours and burned ~$6,000 overnight
Individual developer (r/ClaudeAI report) · May 1, 2026 · Coding agent
What happened
A developer set a single /loop command to check open pull requests every 30 minutes and forgot about it. The loop ran 46 times over 26 hours on claude-opus-4-7, unattended and overnight. Together with a long analytics session, the two sessions burned roughly $6,000 before the developer woke up. The Anthropic dashboard had a multi-day reporting lag and still showed only a fraction of the true spend when checked, so the first warning was the usage-limit email. The reporter also noted that every Claude API call re-sends the entire conversation history, which multiplied the cost of each of the 46 runs.
Causal vector
Scheduled /loop mode left running unattended with no per-session cost ceiling; full-context resends multiplied the bill on every cycle
Source
Reported by Reddit r/ClaudeAI (first-hand report). Verified against the primary report.
46 identical scheduled runs in 26 hours is a velocity signature, not a normal workload: a spend firewall with a daily ceiling or per-hour velocity limit returns BLOCKED on the run that crosses the bound, long before a six-thousand-dollar overnight loop completes.
The six rule types that contain this class of failure
Per-transaction cap
Any single spend above your ceiling is BLOCKED before it moves.
Daily total
Cumulative spend across all agent calls, bounded per day.
Velocity limit
Stops runaway retry loops — the #1 cause of overnight losses.
Merchant allowlist
Only approved destinations can ever receive funds.
Category rules
Flag high-risk classes (crypto, infra, refunds) for review.
Approval threshold
Above a value, the action waits for a human.
Related incidents
Stanford Digital Economy Lab: agentic coding tasks consume ~1,000x more tokens than chat, with up to 30x variance on the same task
Stanford Digital Economy Lab · May 5, 2026
Claude Code entered an infinite loop, re-sending the same requests for hours and burning $500+ in tokens
Claude Code user (GitHub issue 35166) · Mar 17, 2026
Runaway while-loop in Claude agent burns ~$47,000 in API tokens overnight
anonymous (engineering post-mortem) · Dec 1, 2025
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