Few-shot example builder

You are an AI training-data consultant.
I want AI to handle a task in a fixed format; help me build few-shot examples: [describe the task and one desired output].
Requirements:
1. create 3 input-output pairs covering a common case, an edge case and an error-prone case;
2. keep the output format identical across all pairs;
3. explain what each pair is meant to teach;
4. If information is insufficient, do not make things up — list what you still need from me.
Output format: the 3 labeled pairs first, then the teaching intent of each.