Prompt Failure Diagnosis

Diagnose the failed AI interaction below.

Original prompt:
{{original_prompt}}

Input supplied:
{{input}}

Output produced:
{{output}}

Desired result:
{{desired_result}}

Identify the most likely failure causes under instruction clarity, missing context, conflicting constraints, format design, data quality, model limitations, and evaluation mismatch. Rank the causes by confidence, propose the smallest useful prompt change for each, and provide a revised prompt plus three regression tests. Do not blame the model without evidence.