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{
  "id": 3456,
  "title": "Winter Break Schedule",
  "content": "School will be closed from December 23rd to January 3rd. Classes resume January 6th, 2026.",
  "scope": "school",
  "class_id": null,
  "grade_level": null,
  "priority": "high",
  "author_id": 567,
  "published_at": "2025-12-15T09:00:00Z",
  "expires_at": "2026-01-06T08:00:00Z",
  "created_at": "2025-12-14T16:30:00Z"
}

{
  "error": "Invalid API key",
  "code": "UNAUTHORIZED",
  "status": 401
}

{
  "error": "Student not found",
  "code": "NOT_FOUND",
  "status": 404
}