AI-authored code contains worse bugs than software crafted by humans
CodeRabbit review of pull requests shows meatbags beat clankers

Generating code using AI increases the number of issues that need to be reviewed and the severity of those issues.

CodeRabbit, an AI-based code review platform, made that determination by looking at 470 open source pull requests for its State of AI vs Human Code Generation report.

The report finds that AI-generated code contains significantly more defects of logic, maintainability, security, and performance than code created by people.

On average, AI-generated pull requests (PRs) include about 10.83 issues each, compared with 6.45 issues in human-generated PRs. That's about 1.7x more when AI is involved, meaning longer code reviews and increased risk of defects.

Problems caused by AI-generated PRs also tend to be more severe than human-made messes. AI-authored PRs contain 1.4x more critical issues and 1.7x more major issues on average than human-written PRs, the report says.

Machine-generated code therefore seems to require reviewers to deal with a large volume of issues that are more severe than those present in human-generated code.

These findings echo a report issued last month by Cortex, maker of an AI developer portal. The company's Engineering in the Age of AI: 2026 Benchmark Report [PDF] found that PRs per author increased 20 percent year-over-year even as incidents per pull request increased by 23.5 percent, and change failure rates rose around 30 percent.

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