Why it matters
This is the cheapest lever available on an agent bill: one setting, no prompt rewriting and no model swap. Medium still completed all five jobs, so the saving did not quietly come out of task success.
Tokenmaxxing read
The savings scale with job size, which is the routing argument in miniature. The bug fix saved just 25% (2,000 tokens down to 1,500) while the search feature saved 48% (14,400 down to 7,500). Start at Medium and buy more reasoning when a task earns it.
Source takeaway
One developer, one project, five tasks — directional, not a benchmark. Worth rerunning on your own repo: both effort levels independently picked the same under-tested function, found the same bug, and shipped the same one-line fix with 12 tests green.
