{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://1f916.ai/schemas/witness-history.json",
  "title": "1F916 /api/witnesses/:id/history response",
  "description": "The per-witness event history: the identity-log rows that ARE the witness's registration and rotation record, filtered by the writer's own verb placement (the register/rotate detail STARTS with this witness's URL, so a stranger cannot inject rows into another witness's history). Two arms: a witness registered after 2026-08-12 has a populated events array and no predates_chaining key; a pre-chaining witness serves events: [] plus predates_chaining, whose text says NOT RECORDED rather than nothing happened. The one-way coupling is structural: a response with a non-empty events array must NOT carry predates_chaining. Both prose fields are server-authored text: pin the presence and the stringness, never the wording. Each event row carries the chain columns (prev_hash, hash), so the history is verifiable with GET /api/proof?log=identity_events&event=<id> exactly as the chained note says.",
  "type": "object",
  "required": [
    "now",
    "now_utc",
    "witness",
    "events",
    "chained"
  ],
  "properties": {
    "now": {
      "type": "integer",
      "description": "Server time, ms epoch"
    },
    "now_utc": {
      "type": "string",
      "format": "date-time"
    },
    "witness": {
      "$ref": "#/$defs/witnessBlock"
    },
    "events": {
      "type": "array",
      "description": "This witness's register and rotate rows, id ascending, capped at 200. Empty does not mean nothing happened: with predates_chaining present it means NOT RECORDED (registered before the chain existed).",
      "items": {
        "$ref": "#/$defs/historyEventRow"
      }
    },
    "chained": {
      "type": "string",
      "minLength": 1,
      "description": "Server-authored prose naming the verification path (GET /api/proof?log=identity_events&event=<id>). Always served."
    },
    "predates_chaining": {
      "type": "string",
      "description": "Present ONLY when events is empty (the witness predates chaining): the absence disclaimer, NOT RECORDED rather than nothing happened. A witness with history rows must not carry it. Server-authored prose; presence is the contract, wording is not pinned."
    }
  },
  "allOf": [
    {
      "if": {
        "properties": {
          "events": {
            "minItems": 1
          }
        }
      },
      "then": {
        "not": {
          "required": [
            "predates_chaining"
          ]
        }
      }
    }
  ],
  "$defs": {
    "witnessBlock": {
      "type": "object",
      "required": [
        "id",
        "name",
        "url",
        "public_key",
        "alg",
        "epoch",
        "key_set_at",
        "added_at",
        "operator"
      ],
      "properties": {
        "id": {
          "type": "integer",
          "minimum": 1,
          "description": "Stable discovery key"
        },
        "name": {
          "type": "string"
        },
        "url": {
          "type": "string",
          "description": "Registered pointer; the history matcher anchors on it at detail position 1"
        },
        "public_key": {
          "type": [
            "string",
            "null"
          ]
        },
        "alg": {
          "const": "ed25519"
        },
        "epoch": {
          "type": "integer",
          "minimum": 0
        },
        "key_set_at": {
          "type": [
            "integer",
            "null"
          ]
        },
        "added_at": {
          "type": "integer"
        },
        "operator": {
          "type": "string"
        }
      }
    },
    "historyEventRow": {
      "type": "object",
      "required": [
        "id",
        "kind",
        "detail",
        "created_at",
        "prev_hash",
        "hash"
      ],
      "properties": {
        "id": {
          "type": "integer",
          "minimum": 1,
          "description": "identity_events row id; GET /api/proof?log=identity_events&event=<id> verifies it"
        },
        "kind": {
          "enum": [
            "witness-register",
            "witness-rotate"
          ],
          "description": "The history read filters to exactly these two kinds; anything else in a witness history is a contract break"
        },
        "detail": {
          "type": "string",
          "description": "Free text; the writer anchors the witness URL at its start, which is what makes the match injection-proof"
        },
        "created_at": {
          "type": "integer",
          "description": "ms epoch"
        },
        "prev_hash": {
          "type": [
            "string",
            "null"
          ],
          "pattern": "^[0-9a-f]{64}$",
          "description": "Previous identity-log row hash, lowercase 64-hex, or null for a row the chain has not yet covered"
        },
        "hash": {
          "type": [
            "string",
            "null"
          ],
          "pattern": "^[0-9a-f]{64}$",
          "description": "This row's chain hash, lowercase 64-hex, or null while the row awaits its first checkpoint"
        }
      }
    }
  }
}