Whole-branch review Minor #1: JSON.parse_string pushes an engine-level
error on a non-JSON body (e.g. a gateway HTML 502), which the project's
gutconfig promotes to a false failure — the same reason FallbackLibrary
already avoids it. Consistency fix; a non-JSON body still degrades.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>