Incidents/ By cause/ Unattended sessions/ cline-burn-rate-shock
BLOCK Unattended sessions Multiple developer 2025

Opaque per-token pricing triggered billing shock

Developers reported billing shock from high token burn rates and opaque pay-as-you-go pricing on coding agents, with several exceeding expected daily budgets by an order of magnitude.

Reported lossCost not disclosed
ConfidencePartial — some details unconfirmed
Which rule would have stopped this?

An agent ran without supervision while the operator was asleep or away, accumulating charges for hours. The fix is a time-of-day rule and a hard daily cap. time-of-day + daily total would have rejected or flagged this transaction before any money moved.

Per-transaction cap
A single runaway purchase, a fat-finger API call, or an attacker testing how much they can move at once.
max_amount_usd: 500
Daily / period total
A loop that's individually small but runs thousands of times overnight.
daily_max_usd: 200
Category rule
A GPU splurge draining the budget meant for SaaS tools.
category: compute, daily_max_usd: 50
Time-of-day rule
The 3am session nobody is watching.
block_after: "22:00", block_before: "07:00"

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What happened

Developers reported billing shock from high token burn rates and opaque pay-as-you-go pricing on coding agents, with several exceeding expected daily budgets by an order of magnitude.

The root cause was classified as Unattended / overnight session. An agent ran without supervision while the operator was asleep or away, accumulating charges for hours. The fix is a time-of-day rule and a hard daily cap.

This is one of 14 documented incidents in the open registry. Every entry is sourced to a public URL; amounts and dates are as reported by the source.

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