You are reviewing the attached corpus for internal contradictions.

A contradiction means two statements that cannot both be true within the same scope (same entity, same time period, same conditions). Distinguish a real contradiction from a general rule with a more-specific exception, from different effective periods of the same predicate, and from compatible permissions and obligations.

Return JSON only, with no surrounding prose. Use exactly this shape:

[
  {
    "doc_a": "<filename or short title of first document>",
    "span_a": "<verbatim sentence from doc_a>",
    "doc_b": "<filename or short title of second document>",
    "span_b": "<verbatim sentence from doc_b>",
    "type": "contradiction" | "scope_mismatch" | "ambiguous",
    "rationale": "<one sentence explaining why these two cannot both be true>"
  }
]

Be conservative. When in doubt, omit. Prefer 5 clear findings over 30 hedged ones.
