blast-area
Map a change's blast area
"What will this break?" is usually answered with a list of files. A list of files is not a decision. It says where to look, not what happens, not when, and not what the list left out — and the changes that hurt are precisely the ones whose damage was never a file a search would have returned. A column name inside a string literal. A job that stops registering and simply never runs. A guard that starts passing because its pattern now matches nothing. A prompt row in a table naming a tool that got renamed.
This skill produces a decision surface instead: twelve effect surfaces walked in a fixed order; when each break would surface — compile time, runtime, or silently — stated per item; a deploy ordering with the reason it is that way round; the searches that established every empty cell; and a mandatory statement of what the map could not see, at a confidence drawn from five fixed words.
It maps. It changes nothing, and it commits nothing unless a run record is asked for.