prefetch — auto

No prefetch export, so this follows the app-wide partialPrefetching setting. Writing prefetch = 'auto' explicitly is discouraged — omitting it means the same thing.

What to check

Reach this page by clicking from /prefetch in a build with the network tab open, and compare against the other two destinations. The content below is deliberately the same in all three.

Destination content

probe-shell — App Shell eligible

use cache
cacheLife
probe-shell
upstream
247ms

ran at exec jeprj6age …

probe 911,151

Identical in all three prefetch destinations, so any difference you observe is the segment config and nothing else.