Phantom Changes in Agent PRs
AI-agent PRs fail at description-vs-diff, not at code. Phantom changes (45%), scope understated (22%), placeholder (19%). Don't trust the agent's own description.
The dominant failure mode in AI-coding-agent pull requests isn't bugs in the code — it's message-code inconsistency. The PR description claims one set of changes, the diff shows another. Recent analyses break the pattern into three buckets: phantom changes (claimed but not done, ~45%), scope understated (done but not described, ~22%), and placeholder/incomplete (started but unfinished, ~19%).
The implication for any team using coding agents: don't trust the agent's own description of its work. The minimum reviewer ritual is to ignore the PR title and read the diff. The maximum is automated diff-vs-description verification before the PR even gets a human.
This is a new class of code review skill. It will be required at every shop running agents within twelve months.