Internal
Amazon documents released this week reveal several AI cost overruns. The largest involved a $1.8 million project using
Anthropic's Claude Sonnet model, which exceeded its budget by 860% and was never launched.
Amazon did not detect the overspending for five months. Senior engineers reported the overruns at a staff meeting on Tuesday, July 28. The tool was designed to automatically match author details to product listings on Amazon's site.
Two additional projects also exceeded their budgets during this period, bringing total unplanned AI spending to approximately $2.5 million.
Largest Amazon AI Overrun Exposed in Internal Documents
The Claude Sonnet author-matching tool accounted for the largest overrun at $1.8 million, exceeding its budget by 860% and never launching.
A financial auditing tool exceeded its budget by approximately $541,000, while a logistics system designed to accelerate deliveries ran $134,000 over budget.
Together, the three projects resulted in approximately $2.5 million in unplanned AI spending. This figure is small relative to Amazon's scale, citing $181.5 billion in revenue and $23.9 billion in operating income for the first quarter of 2026.
Engineers attributed the overruns to a shift in AI provider billing models. Many providers now bill based on tokens, or units of processed text, rather than flat monthly subscriptions.