Cognition SWE-2 vs Fable 5.1: Where It Wins and Loses

Cognition released SWE-2 on 10 September 2026 and one number travelled: 50.0% on FrontierCode 1.1 Main, within a point of Fable 5.1, at 64% lower cost. Three rows below it, in the same table, is a number that did not.