Root cause location

Data flow chain documented

Fix at data source

Return type guaranteed

No sole suppression at crash site

Proximate vs root cause distinguished

Similar pattern check

Contract considered

Root cause explanation quality

Primary crash fixed

Primary root cause addressed

Secondary error identified

Secondary error code changed

Secondary fix not another silent catch

Both issues addressed in analysis

Breadcrumb sequence used

Changes in multiple files

Root cause identified

Fix at boundary

Existing validation utility used

No new validation abstraction

Required fields enumerated

Existing error type used

Pattern inconsistency noted

Defense in depth after root cause