{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://ethotechnics.org/standards/challenge.schema.json",
  "title": "Challenge",
  "description": "An instance of standing being exercised: a party listed in a standing register contests a decision, a grant, or a policy. A challenge is how exposure enters the system as an event (Law VII) and what forces a reconsideration.",
  "type": "object",
  "required": [
    "schema_version",
    "challenge_id",
    "register_ref",
    "decision_class",
    "subject",
    "challenger",
    "opened_at",
    "evidence",
    "responder",
    "deadline",
    "status"
  ],
  "additionalProperties": false,
  "properties": {
    "schema_version": {
      "title": "Schema version",
      "description": "Version of this schema the challenge conforms to.",
      "type": "string",
      "pattern": "^1\\.\\d+\\.\\d+$"
    },
    "challenge_id": {
      "title": "Challenge identifier",
      "description": "Stable identifier for the challenge.",
      "type": "string"
    },
    "register_ref": {
      "title": "Register reference",
      "description": "Identifier of the standing register entry that grants the challenger standing.",
      "type": "string"
    },
    "decision_class": {
      "title": "Decision class",
      "description": "The decision class in the register under which the challenge is brought.",
      "type": "string"
    },
    "subject": {
      "title": "Subject",
      "description": "What is being challenged.",
      "type": "object",
      "required": ["kind", "ref"],
      "additionalProperties": false,
      "properties": {
        "kind": {
          "title": "Kind",
          "description": "Whether the challenge targets a decision, a grant, or a policy.",
          "type": "string",
          "enum": ["decision", "grant", "policy"]
        },
        "ref": {
          "title": "Reference",
          "description": "Identifier of the decision record, grant, or policy record.",
          "type": "string"
        }
      }
    },
    "challenger": {
      "title": "Challenger",
      "description": "Who brought the challenge and on what basis they have standing.",
      "type": "object",
      "required": ["standing_basis"],
      "additionalProperties": false,
      "properties": {
        "standing_basis": {
          "title": "Standing basis",
          "description": "The exposure that gives the challenger standing.",
          "type": "string",
          "enum": [
            "affected_party",
            "corrective_labor",
            "representative",
            "oversight"
          ]
        },
        "id": {
          "title": "Challenger identifier",
          "description": "Identifier of the challenger, if disclosed.",
          "type": "string"
        }
      }
    },
    "opened_at": {
      "title": "Opened at",
      "description": "When the challenge was opened.",
      "type": "string",
      "format": "date-time"
    },
    "evidence": {
      "title": "Evidence",
      "description": "Evidence submitted with the challenge.",
      "type": "array",
      "items": {
        "title": "Evidence item",
        "description": "One piece of submitted evidence.",
        "type": "object",
        "required": ["type", "href"],
        "additionalProperties": false,
        "properties": {
          "type": {
            "title": "Type",
            "description": "Kind of evidence, matching an admissible_evidence entry in the register.",
            "type": "string"
          },
          "href": {
            "title": "Link",
            "description": "Where the evidence can be retrieved.",
            "type": "string"
          },
          "description": {
            "title": "Description",
            "description": "Plain-language summary of the evidence.",
            "type": "string"
          }
        }
      }
    },
    "responder": {
      "title": "Responder",
      "description": "The accountable person or role who must answer.",
      "type": "object",
      "required": ["name", "role", "contact"],
      "additionalProperties": false,
      "properties": {
        "name": {
          "title": "Name",
          "description": "Name of the responder.",
          "type": "string"
        },
        "role": {
          "title": "Role",
          "description": "Role of the responder.",
          "type": "string"
        },
        "contact": {
          "title": "Contact",
          "description": "How to reach the responder.",
          "type": "string"
        }
      }
    },
    "deadline": {
      "title": "Deadline",
      "description": "When the responder must answer, computed from the register's response_deadline.",
      "type": "string",
      "format": "date-time"
    },
    "status": {
      "title": "Status",
      "description": "Lifecycle status of the challenge.",
      "type": "string",
      "enum": ["open", "under_review", "decided", "withdrawn"]
    },
    "reconsideration_ref": {
      "title": "Reconsideration reference",
      "description": "Identifier of the reconsideration record the challenge triggered.",
      "type": "string"
    },
    "outcome": {
      "title": "Outcome",
      "description": "How the challenge was decided.",
      "type": "object",
      "required": ["transition", "reason", "decided_at"],
      "additionalProperties": false,
      "properties": {
        "transition": {
          "title": "Transition",
          "description": "The state transition the challenge produced, matching reconsideration outcomes.",
          "type": "string",
          "enum": ["stand", "narrow", "suspend", "reverse", "correct", "expand"]
        },
        "reason": {
          "title": "Reason",
          "description": "Plain-language reason for the outcome.",
          "type": "string"
        },
        "decided_at": {
          "title": "Decided at",
          "description": "When the outcome was recorded.",
          "type": "string",
          "format": "date-time"
        }
      }
    }
  }
}