{
  "illustrative": true,
  "descriptionClassification": "deterministic heuristic, not measured model behavior",
  "examples": [
    {
      "id": "required-input",
      "title": "Make an optional argument required",
      "explanation": "An existing call with only query stops validating when limit becomes required. Keep the previous default during migration.",
      "severity": "BREAKING",
      "page": "https://mcprobe.dev/examples#required-input",
      "before": "https://mcprobe.dev/examples/required-input/before.json",
      "after": "https://mcprobe.dev/examples/required-input/after.json",
      "diff": "https://mcprobe.dev/examples/required-input/diff.json"
    },
    {
      "id": "widen-input-enum",
      "title": "Accept another input enum value",
      "explanation": "Adding archived to the accepted input values preserves existing calls. This is the input direction; returning a new value has a different verdict.",
      "severity": "NON_BREAKING",
      "page": "https://mcprobe.dev/examples#widen-input-enum",
      "before": "https://mcprobe.dev/examples/widen-input-enum/before.json",
      "after": "https://mcprobe.dev/examples/widen-input-enum/after.json",
      "diff": "https://mcprobe.dev/examples/widen-input-enum/diff.json"
    },
    {
      "id": "widen-output-enum",
      "title": "Return another output enum value",
      "explanation": "A caller handling only open and closed may fail when the server returns archived. The same enum expansion is breaking in the output direction.",
      "severity": "BREAKING",
      "page": "https://mcprobe.dev/examples#widen-output-enum",
      "before": "https://mcprobe.dev/examples/widen-output-enum/before.json",
      "after": "https://mcprobe.dev/examples/widen-output-enum/after.json",
      "diff": "https://mcprobe.dev/examples/widen-output-enum/diff.json"
    },
    {
      "id": "description-rewrite",
      "title": "Rewrite a tool description",
      "explanation": "The input schema is unchanged, but the model-visible purpose changes. The finding is a deterministic review heuristic; test tool selection with your own evaluations.",
      "severity": "POTENTIALLY_BREAKING",
      "page": "https://mcprobe.dev/examples#description-rewrite",
      "before": "https://mcprobe.dev/examples/description-rewrite/before.json",
      "after": "https://mcprobe.dev/examples/description-rewrite/after.json",
      "diff": "https://mcprobe.dev/examples/description-rewrite/diff.json"
    }
  ]
}