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 · Coding agent
What happened
A user filed a bug report after Claude Code entered an infinite loop: the agent repeatedly sent the same requests for several hours at roughly one-minute intervals, producing no useful output or tool calls, and racked up more than $500 of unexpected token usage. The user asked for automatic detection of repeated request patterns and a stop after a reasonable retry count.
Causal vector
Unbounded retry loop, identical requests re-sent hundreds of times with no duplicate detection or stop condition
Source
Reported by GitHub issue, anthropics/claude-code 35166. Verified against the primary report.
A one-minute-interval loop of identical calls is the clearest possible anomaly signal: a firewall that counts repeated tool calls per session and blocks the Nth identical retry would have stopped this inside the first hour instead of letting it run for several.
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
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
Runaway while-loop in Claude agent burns ~$47,000 in API tokens overnight
anonymous (engineering post-mortem) · Dec 1, 2025
Don't be the next entry
Every incident in this database is the result of trusting a prompt, a provider cap, or a human review cycle. sipi.bot replaces all three with one deterministic call. 67 documented failures, one control.