“In both instances, this was user error, not AI error,” Amazon said, adding that it had not seen evidence that mistakes were more common with AI tools.

The company said the incident in December was an “extremely limited event” affecting only a single service in parts of mainland China. Amazon added that the second incident did not have an impact on a “customer facing AWS service.”

Neither disruption was anywhere near as severe as a 15-hour AWS outage in October 2025 that forced multiple customers’ apps and websites offline—including OpenAI’s ChatGPT.

Employees said the group’s AI tools were treated as an extension of an operator and given the same permissions. In these two cases, the engineers involved did not require a second person’s approval before making changes, as would normally be the case.

Amazon said that by default its Kiro tool “requests authorisation before taking any action” but said the engineer involved in the December incident had “broader permissions than expected—a user access control issue, not an AI autonomy issue.”

AWS launched Kiro in July. It said the coding assistant would advance beyond “vibe coding”—which allows users to quickly build applications—to instead write code based on a set of specifications.

The group had earlier relied on its Amazon Q Developer product, an AI-enabled chatbot, to help engineers write code. This was involved in the earlier outage, three of the employees said.

Some Amazon employees said they were still skeptical of AI tools’ utility for the bulk of their work given the risk of error. They added that the company had set a target for 80 percent of developers to use AI for coding tasks at least once a week and was closely tracking adoption.

Amazon said it was experiencing strong customer growth for Kiro and that it wanted customers and employees to benefit from efficiency gains.

“Following the December incident, AWS implemented numerous safeguards,” including mandatory peer review and staff training, Amazon added.

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