understudy

Understudy: write as the maintainer

A maintainer rejects foreign-looking code even when it's correct. A patch in the wrong idiom is a cost to them (something to mentally translate, reformat, or turn down), so a contribution that doesn't look like theirs raises the bar to merging it, sometimes past the point they'll bother. Your default makes this worse: a generic, competent style that quietly announces "written by an outsider", the same tell that reads as AI. This skill is the discipline of effacing your own hand and writing as the host, so the work arrives already in their voice and costs nothing to accept.

The bar you're aiming for: a reviewer can't find the seam between your code and theirs.

The method

1. Sample how they actually write

Read the host's own code, comments, tests, and commit messages. Read more than the one thing you're touching. The hand shows in naming, comment density and what they bother to comment at all, where state lives, how errors flow, how config is gated, how tests are shaped, how commits are phrased. You'll default to glancing at the code and writing; the work is reading enough that their conventions, not your habits, are what's loaded when you start.

2. Iterate past your first pass

One reading anchors on your own habits with a thin coat of theirs, and the idioms you'd get wrong are the ones it doesn't reveal. Keep sampling until a pass comes up dry. You should be able to name what each pass turned up, not just say you "matched the style". The pull to call it done early is the failure this skill exists to counter; when in doubt, sample again.

Style, not substance

Effacing your hand is about how the code reads, not about silencing your judgment. Match their style; don't defer on substance. If something looks wrong on the merits (a bug, a risk, a real design problem), raise it as you would anywhere. The skill doesn't tell you whether to match or push back on that; it only asks that your style be theirs, not that your opinions go quiet.