{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://tylereno.me/oidf/schemas/handoff_ledger.json",
  "title": "OIDFHandoffLedger",
  "description": "Immutable digital as-built / handoff package for an asset or deployment.",
  "type": "object",
  "additionalProperties": false,
  "required": ["ledger_id", "spec_version", "subject", "created_at", "entries"],
  "properties": {
    "ledger_id": { "type": "string", "minLength": 1 },
    "spec_version": { "type": "string", "const": "1.0.0" },
    "subject": {
      "type": "object",
      "additionalProperties": false,
      "required": ["kind", "id"],
      "properties": {
        "kind": { "type": "string", "enum": ["Asset", "Deployment"] },
        "id": { "type": "string", "minLength": 1 },
        "label": { "type": "string" }
      }
    },
    "created_at": { "type": "string", "format": "date-time" },
    "baseline_id": { "type": "string" },
    "machine_definition_id": { "type": "string" },
    "entries": {
      "type": "array",
      "minItems": 1,
      "items": {
        "type": "object",
        "additionalProperties": false,
        "required": ["seq", "occurred_at", "from_state", "to_state", "evidence_refs"],
        "properties": {
          "seq": { "type": "integer", "minimum": 1 },
          "occurred_at": { "type": "string", "format": "date-time" },
          "from_state": { "type": "string" },
          "to_state": { "type": "string" },
          "actor_id": { "type": "string" },
          "evidence_refs": {
            "type": "array",
            "minItems": 1,
            "items": { "type": "string", "minLength": 1 },
            "description": "Non-empty Evidence IDs that unlocked this transition. Empty arrays are schema-invalid."
          },
          "sat_event_ids": {
            "type": "array",
            "items": { "type": "string" }
          },
          "notes": { "type": "string" }
        }
      }
    }
  }
}