```json
[
    {
        "issue": "Incorrect data type for candidates parameter in get_first_contexts method",
        "evidence": "def get_first_contexts(candidates: [dict], mask=None):",
        "description": "The 'candidates' parameter should be a list of dictionaries, but the annotation '[dict]' is incorrect. The correct syntax is 'List[dict]', which is the standard type hint in Python. This mistake could confuse users about the expected data type."
    },
    {
        "issue": "Incorrect handling of dataset structure in get_examples method",
        "evidence": "for word_type in ['n', 'v']: \n sample_groups = CoDA[word_type]",
        "description": "The method assumes 'CoDA' contains keys 'n' and 'v' mapping to lists. If 'CoDA' doesn't follow this structure, a KeyError will occur. There should be a validation check for data types and key presence before accessing them."
    }
]
```