Study Finds AI-Generated Code Fails to Boost Productivity Due to Downstream Bottlenecks
InfoQ, Thursday, October 22nd, 2026
A Harvard study of 700+ firms finds AI agents lift code volume about 30% but resolved work only 12%, as review becomes the bottleneck.
InfoQ reports on a Harvard study that used Jellyfish data covering roughly 300 million work events at more than 700 firms.
AI coding assistants produced small gains in lines, commits and pull requests, while agents raised them 20-30%, but resolved Jira issues rose only 12% with agents and not at all with assistants.
The researchers estimate engineers spend just 30-40% of their time writing code.
More AI-generated code shifts work to reviews, testing and deployment, which limits overall gains unless those stages also improve.