GPT-5.5 Codex reasoning-token clustering may be leading to degraded performance
gpt-5.5codexreasoning-tokenclusteringmodel-behaviormachine-learningaisoftware-developmentmodel-performancedegraded-performance
Author: maille
Date: 7/4/2026
Article Summary:
A GitHub issue reporting a potential issue with the GPT-5.5 Codex model, where it disproportionately clusters at exact reasoning-token counts of 516, 1034, and 1552, leading to degraded performance on complex tasks.