{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://schema.openpx.org/v0.6.3/openpx-schema.json",
  "title": "OpenPX V0.6.3 Schema",
  "description": "JSON Schema validation rules for Open Product Exchange V0.6.3 — compliance.hazmat.un_regulatory_id now accepts an optional trailing letter (`^UN\\d{4}[a-zA-Z]?$`), so real UN sub-divisions such as `UN3481b` validate (#2097). V0.6.2 made multi-word enum values now use the CANONICAL space form (`not applicable`, `compressed gas`, `works with`), matching term.canonical_value; the underscore form is a channel representation produced by value_mapping on export and is no longer accepted (#2088). BREAKING for anything emitting the underscore form. V0.6.1 added content.seo_title/seo_description (#1724); V0.6.0 added product/variant channel_content (#1718)",
  "type": "object",
  "required": ["openpx"],
  "properties": {
    "openpx": {
      "type": "string",
      "pattern": "^\\d+\\.\\d+\\.\\d+$",
      "description": "OpenPX schema version"
    },
    "organization": {
      "$ref": "#/definitions/organization"
    },
    "brand": {
      "$ref": "#/definitions/brand"
    },
    "product": {
      "$ref": "#/definitions/product"
    },
    "variant": {
      "$ref": "#/definitions/variant"
    },
    "listing": {
      "$ref": "#/definitions/listing"
    },
    "signature": {
      "$ref": "#/definitions/signature"
    }
  },
  "definitions": {
    "uuid": {
      "type": "string",
      "pattern": "^[0-9a-f]{8}-[0-9a-f]{4}-7[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$",
      "description": "UUID v7 format (RFC 9562) - time-ordered, monotonic"
    },
    "organization_identifiers": {
      "type": "object",
      "required": ["slug"],
      "properties": {
        "slug": {
          "type": "string",
          "minLength": 1,
          "maxLength": 100,
          "pattern": "^[a-z0-9](-?[a-z0-9])*$",
          "description": "URL-safe identifier (lowercase, hyphens allowed). Cannot start or end with a hyphen, and no consecutive hyphens."
        },
        "duns": {
          "type": ["string", "null"],
          "pattern": "^\\d{9}$",
          "description": "D-U-N-S Number (9 digits)"
        },
        "gln": {
          "type": ["string", "null"],
          "pattern": "^\\d{13}$",
          "description": "GS1 Global Location Number (13 digits)"
        }
      }
    },
    "brand_identifiers": {
      "type": "object",
      "required": ["slug"],
      "properties": {
        "slug": {
          "type": "string",
          "minLength": 1,
          "maxLength": 100,
          "pattern": "^[a-z0-9](-?[a-z0-9])*$",
          "description": "URL-safe identifier within organization (lowercase, hyphens allowed). Cannot start or end with a hyphen, and no consecutive hyphens."
        }
      }
    },
    "organization": {
      "type": "object",
      "required": ["id", "name", "identifiers"],
      "properties": {
        "id": {
          "$ref": "#/definitions/uuid"
        },
        "name": {
          "type": "string",
          "minLength": 1,
          "maxLength": 255
        },
        "identifiers": {
          "$ref": "#/definitions/organization_identifiers"
        },
        "logo_url": {
          "type": "string",
          "format": "uri",
          "maxLength": 2048
        },
        "description": {
          "type": "string",
          "maxLength": 10000
        },
        "website": {
          "type": "string",
          "format": "uri",
          "maxLength": 2048
        },
        "status": {
          "type": "string",
          "enum": ["draft", "active", "archived"]
        },
        "metadata": {
          "type": "object",
          "additionalProperties": true
        },
        "signing": {
          "type": "object",
          "required": ["key_ref", "algorithm"],
          "properties": {
            "key_ref": {
              "type": "string",
              "pattern": "^\\.openpx/keys/[a-z0-9_-]+-\\d{4}-\\d{2}-\\d{2}\\.pub$",
              "description": "Path to the organization's public signing key"
            },
            "algorithm": {
              "type": "string",
              "enum": ["Ed25519"],
              "description": "Signing algorithm used by this organization"
            }
          }
        }
      }
    },
    "brand": {
      "type": "object",
      "required": ["id", "organization_id", "name", "identifiers"],
      "properties": {
        "id": {
          "$ref": "#/definitions/uuid"
        },
        "organization_id": {
          "$ref": "#/definitions/uuid"
        },
        "name": {
          "type": "string",
          "minLength": 1,
          "maxLength": 255
        },
        "identifiers": {
          "$ref": "#/definitions/brand_identifiers"
        },
        "logo_url": {
          "type": "string",
          "format": "uri"
        },
        "story": {
          "type": "string",
          "maxLength": 5000
        },
        "values": {
          "type": "array",
          "items": {
            "type": "string",
            "minLength": 1,
            "maxLength": 100
          },
          "maxItems": 10
        },
        "website": {
          "type": "string",
          "format": "uri",
          "maxLength": 2048
        },
        "status": {
          "type": "string",
          "enum": ["draft", "active", "archived"]
        },
        "metadata": {
          "type": "object",
          "additionalProperties": true
        },
        "access_control": {
          "$ref": "#/definitions/access_control"
        }
      }
    },
    "product": {
      "type": "object",
      "required": ["id", "brand_id", "status", "identifiers", "classification", "content"],
      "properties": {
        "id": {
          "$ref": "#/definitions/uuid"
        },
        "brand_id": {
          "$ref": "#/definitions/uuid"
        },
        "status": {
          "type": "string",
          "enum": ["draft", "active", "archived"]
        },
        "content": {
          "allOf": [
            { "$ref": "#/definitions/content" },
            { "required": ["locale", "name", "description_short"] }
          ]
        },
        "condition": {
          "type": "string",
          "enum": ["new", "used", "refurbished"],
          "description": "Product condition. Defaults to 'new' if not specified."
        },
        "identifiers": {
          "type": "object",
          "anyOf": [
            {"required": ["sku"]},
            {"required": ["gtin"]},
            {"required": ["upc"]},
            {"required": ["ean"]},
            {"required": ["mpn"]},
            {"required": ["model_number"]},
            {"required": ["usda_fdc_id"]},
            {"required": ["asin"]},
            {"required": ["nsn"]}
          ],
          "properties": {
            "sku": {
              "type": "string",
              "minLength": 1,
              "maxLength": 100
            },
            "gtin": {
              "type": "string",
              "pattern": "^\\d{8,14}$",
              "description": "Global Trade Item Number (GTIN-8/12/13/14)"
            },
            "upc": {
              "type": "string",
              "pattern": "^\\d{12}$",
              "description": "Universal Product Code (12 digits)"
            },
            "ean": {
              "type": "string",
              "pattern": "^\\d{13}$",
              "description": "European Article Number (13 digits)"
            },
            "mpn": {
              "type": "string",
              "maxLength": 100
            },
            "model_number": {
              "type": "string",
              "maxLength": 100
            },
            "usda_fdc_id": {
              "type": "string",
              "pattern": "^\\d+$",
              "description": "USDA FoodData Central database ID"
            },
            "asin": {
              "type": "string",
              "maxLength": 10,
              "pattern": "^[A-Z0-9]{10}$",
              "description": "Amazon Standard Identification Number (exactly 10 uppercase alphanumeric characters)"
            },
            "nsn": {
              "type": "string",
              "maxLength": 16,
              "pattern": "^[0-9A-Z]{4}-[0-9A-Z]{2}-[0-9A-Z]{3}-[0-9A-Z]{4}$|^[0-9A-Z][0-9A-Z-]{0,15}$",
              "description": "NATO Stock Number — hyphenated NATO form (e.g. 1234-56-789-1234) or local/alphanumeric form (e.g. 850519-S01)"
            }
          }
        },
        "classification": {
          "type": "object",
          "required": ["primary_category"],
          "properties": {
            "primary_category_id": {
              "type": ["string", "null"],
              "pattern": "^[0-9a-f]{8}-[0-9a-f]{4}-7[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$",
              "description": "UUID v7 FK to openpx_category.id (populated after taxonomy tables exist)"
            },
            "primary_category": {
              "type": "string",
              "minLength": 1,
              "maxLength": 500,
              "pattern": "^[a-z][a-z0-9_]*(\\.[a-z][a-z0-9_]*)*$",
              "description": "Dot-separated ltree path (e.g., openpx.food_beverage.bakery.bread)"
            },
            "product_type": {
              "type": "string",
              "minLength": 1,
              "maxLength": 255
            },
            "category_schema_url": {
              "type": "string",
              "format": "uri",
              "description": "URL to category-specific attribute validation schema (optional). If provided, product.attributes will be validated against this schema in addition to base schema."
            },
            "tags": {
              "type": "array",
              "items": {
                "type": "string",
                "minLength": 1,
                "maxLength": 50
              },
              "maxItems": 50
            },
            "external_codes": {
              "type": "object",
              "properties": {
                "unspsc": {
                  "type": "string",
                  "pattern": "^\\d{8}$"
                },
                "eclass": {
                  "type": "string",
                  "pattern": "^\\d{8}$"
                },
                "etim": {
                  "type": "string",
                  "pattern": "^EC\\d{6}$"
                }
              }
            }
          }
        },
        "channel_content": {
          "type": "object",
          "additionalProperties": { "$ref": "#/definitions/content" },
          "description": "Per-channel content variants, keyed by channel identifier (e.g. 'amazon-seller', 'walmart', 'shopify'). Each entry has the shape of `content` (all fields optional, extra keys allowed); sparse-override, deep-merged over `content` when a listing for that channel is created."
        },
        "attributes": { "$ref": "#/definitions/open_attributes" },
        "physical": {
          "$ref": "#/definitions/physical_specifications"
        },
        "media_assets": {
          "$ref": "#/definitions/media_assets"
        },
        "compliance": {
          "$ref": "#/definitions/compliance"
        },
        "assurances": {
          "$ref": "#/definitions/assurances"
        },
        "instructions": {
          "$ref": "#/definitions/instructions"
        },
        "pricing": {
          "$ref": "#/definitions/pricing"
        },
        "relationships": {
          "type": "array",
          "items": { "$ref": "#/definitions/relationship" },
          "maxItems": 100
        },
        "brand_groupings": {
          "$ref": "#/definitions/brand_groupings"
        },
        "technical_data": {
          "type": "object",
          "description": "Measured/tested technical properties grouped by section name",
          "maxProperties": 20,
          "additionalProperties": {
            "type": "array",
            "maxItems": 100,
            "items": {
              "type": "object",
              "minProperties": 1,
              "additionalProperties": {
                "oneOf": [
                  { "type": "string" },
                  { "type": "number" },
                  { "type": "boolean" }
                ]
              }
            }
          }
        },
        "metadata": {
          "type": "object",
          "additionalProperties": true
        },
        "content_hash": {
          "type": ["string", "null"],
          "pattern": "^[a-f0-9]{64}$",
          "description": "SHA-256 hash of canonical JSON representation"
        },
        "variants": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/variant"
          },
          "description": "Embedded variants for this product. Each variant is a sparse override — only include fields that differ from the product."
        },
        "access_control": {
          "$ref": "#/definitions/access_control"
        }
      }
    },
    "media_assets": {
      "type": "object",
      "properties": {
        "images": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/image_asset"
          },
          "maxItems": 50
        },
        "videos": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/video_asset"
          },
          "maxItems": 10
        },
        "documents": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/document_asset"
          },
          "maxItems": 20
        },
        "ar_vr_models": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/ar_vr_asset"
          },
          "maxItems": 5
        }
      }
    },
    "image_asset": {
      "type": "object",
      "required": ["url", "type"],
      "properties": {
        "id": {
          "$ref": "#/definitions/uuid"
        },
        "url": {
          "type": "string",
          "format": "uri"
        },
        "alt_text": {
          "type": "string",
          "maxLength": 255
        },
        "type": {
          "type": "string",
          "enum": ["primary", "alternate", "lifestyle", "detail", "size chart", "ingredient", "nutrition"]
        },
        "width": {
          "type": "integer",
          "minimum": 1
        },
        "height": {
          "type": "integer",
          "minimum": 1
        },
        "format": {
          "type": "string",
          "enum": ["jpg", "png", "webp", "gif"]
        }
      }
    },
    "video_asset": {
      "type": "object",
      "required": ["url", "type"],
      "properties": {
        "id": {
          "$ref": "#/definitions/uuid"
        },
        "url": {
          "type": "string",
          "format": "uri"
        },
        "thumbnail_url": {
          "type": "string",
          "format": "uri"
        },
        "duration_seconds": {
          "type": "integer",
          "minimum": 1
        },
        "type": {
          "type": "string",
          "enum": ["demo", "unboxing", "tutorial", "lifestyle", "testimonial"]
        }
      }
    },
    "document_asset": {
      "type": "object",
      "required": ["url", "type", "title"],
      "properties": {
        "id": {
          "$ref": "#/definitions/uuid"
        },
        "url": {
          "type": "string",
          "format": "uri"
        },
        "type": {
          "type": "string",
          "enum": ["manual", "spec sheet", "warranty", "installation guide", "safety sheet", "catalog"]
        },
        "title": {
          "type": "string",
          "minLength": 1,
          "maxLength": 255
        },
        "locale": {
          "type": "string",
          "pattern": "^[a-z]{2}-[A-Z]{2}$"
        }
      }
    },
    "ar_vr_asset": {
      "type": "object",
      "required": ["url", "format"],
      "properties": {
        "id": {
          "$ref": "#/definitions/uuid"
        },
        "url": {
          "type": "string",
          "format": "uri"
        },
        "format": {
          "type": "string",
          "enum": ["glb", "usdz", "obj", "fbx"]
        },
        "file_size_mb": {
          "type": "number",
          "minimum": 0
        }
      }
    },
    "compliance": {
      "type": "object",
      "properties": {
        "origin": {
          "$ref": "#/definitions/product_origin"
        },
        "certifications": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/certification"
          }
        },
        "warnings": {
          "type": "object",
          "properties": {
            "prop65": {
              "type": "boolean"
            },
            "choking_hazard": {
              "type": "boolean"
            },
            "age_restriction": {
              "type": "string",
              "pattern": "^\\d+\\+$"
            },
            "baa_taa_compliant": {
              "type": "boolean",
              "description": "Compliant with US Buy American Act (BAA) / Trade Agreements Act (TAA) for federal procurement"
            },
            "taa_compliant_country": {
              "type": "string",
              "pattern": "^[A-Z]{2}$",
              "description": "ISO 3166-1 alpha-2 country code asserting TAA compliance (designated country of origin under Trade Agreements Act)"
            }
          }
        },
        "hazmat": {
          "type": "object",
          "description": "Hazardous materials compliance data (regulation, UN code, GHS, SDS URL). Sibling to warnings: warnings carries boolean attestations; hazmat carries structured regulatory data.",
          "properties": {
            "is_hazmat": {
              "type": "boolean",
              "description": "Product classified as hazardous material"
            },
            "regulation": {
              "type": "string",
              "enum": ["ghs", "storage", "transportation", "waste", "other", "not applicable"],
              "description": "Dangerous-goods regulatory framework declaration (mirrors Amazon supplier_declared_dg_hz_regulation)"
            },
            "un_regulatory_id": {
              "type": "string",
              "pattern": "^UN\\d{4}[a-zA-Z]?$",
              "description": "UN regulatory identifier (e.g. UN1993, UN3481b). The optional trailing letter denotes a UN sub-division — Amazon publishes UN3481b for lithium-ion cells packed with equipment (#2097)"
            },
            "ghs_classification": {
              "type": "object",
              "description": "Globally Harmonized System hazard classification",
              "properties": {
                "class": {
                  "type": "string",
                  "enum": [
                    "explosive",
                    "flammable",
                    "oxidizing",
                    "compressed gas",
                    "corrosive",
                    "toxic",
                    "harmful irritant",
                    "health hazard",
                    "environmental hazard",
                    "other"
                  ]
                },
                "category": { "type": "string" },
                "signal_word": {
                  "type": "string",
                  "enum": ["danger", "warning"]
                },
                "hazard_statement": { "type": "string" },
                "h_code": { "type": "string" }
              },
              "additionalProperties": false
            },
            "safety_data_sheet_url": {
              "type": "string",
              "format": "uri",
              "maxLength": 2048,
              "description": "URL to the Safety Data Sheet (SDS or MSDS) document"
            }
          },
          "additionalProperties": false
        },
        "media": {
          "type": "array",
          "description": "URLs to compliance-related media (certificates, declarations, regulatory documents). Generic complement to safety_data_sheet_url under hazmat; used for any compliance regime requiring document attestations.",
          "maxItems": 20,
          "items": {
            "type": "string",
            "format": "uri",
            "maxLength": 2048
          }
        },
        "safety_attestation": {
          "type": "boolean",
          "description": "Attestation that product meets applicable safety regulations for its category and channel scope"
        },
        "gpsr": {
          "type": "object",
          "description": "EU General Product Safety Regulation (GPSR, effective 2024) compliance fields. Article 4 (Responsible Person), Article 9 (Manufacturer obligations).",
          "properties": {
            "manufacturer_reference": {
              "type": "string",
              "description": "GPSR manufacturer identifier (importer/manufacturer reference declaration)"
            },
            "responsible_person": {
              "type": "object",
              "description": "EU-resident Responsible Person contact (Article 4 of GPSR)",
              "properties": {
                "name": { "type": "string" },
                "email": { "type": "string", "format": "email" },
                "address": { "type": "string", "maxLength": 1024 },
                "phone": { "type": "string" }
              },
              "additionalProperties": false
            }
          },
          "additionalProperties": false
        },
        "sustainability": {
          "$ref": "#/definitions/sustainability"
        }
      }
    },
    "sustainability": {
      "type": "object",
      "description": "Sustainability metrics, material claims, carbon footprint, and environmental declarations",
      "properties": {
        "claims": {
          "type": "object",
          "properties": {
            "recyclable": { "type": "boolean" },
            "recycled_content_percent": { "type": "number", "minimum": 0, "maximum": 100 },
            "renewable_materials_percent": { "type": "number", "minimum": 0, "maximum": 100 },
            "compostable": { "type": "boolean" },
            "biodegradable": { "type": "boolean" },
            "green_purchasing_compliant": {
              "type": "boolean",
              "description": "Compliant with US Federal Green Purchasing Law (FAR 23.703 — environmentally preferred products)"
            }
          }
        },
        "carbon": {
          "type": "object",
          "properties": {
            "footprint": {
              "type": "object",
              "required": ["value", "unit", "scope"],
              "properties": {
                "value": { "type": "number", "minimum": 0 },
                "unit": { "type": "string", "enum": ["kgCO2e", "tCO2e"] },
                "scope": { "type": "string", "enum": ["cradle to gate", "cradle to grave", "cradle to cradle"] },
                "standard": { "type": "string", "maxLength": 100 }
              }
            }
          }
        },
        "environmental_declarations": {
          "type": "array",
          "maxItems": 20,
          "items": { "$ref": "#/definitions/environmental_declaration" }
        }
      }
    },
    "environmental_declaration": {
      "type": "object",
      "required": ["type"],
      "properties": {
        "type": { "type": "string", "enum": ["epd", "hpd", "lca"] },
        "standard": { "type": "string", "maxLength": 100 },
        "program_operator": { "type": "string", "maxLength": 200 },
        "registration_number": { "type": "string", "maxLength": 100 },
        "expiry_date": { "type": "string", "format": "date", "description": "ISO 8601 date" },
        "document_url": { "type": "string", "format": "uri", "maxLength": 2000 }
      }
    },
    "product_origin": {
      "type": "object",
      "properties": {
        "country_of_origin": {
          "type": "string",
          "pattern": "^[A-Z]{2}$",
          "description": "ISO 3166-1 alpha-2 country code where raw materials originate"
        },
        "country_of_assembly": {
          "type": "string",
          "pattern": "^[A-Z]{2}$",
          "description": "ISO 3166-1 alpha-2 country code where product is assembled"
        },
        "country_of_last_processing": {
          "type": "string",
          "pattern": "^[A-Z]{2}$",
          "description": "ISO 3166-1 alpha-2 country code where last substantial transformation occurs"
        },
        "country_of_design": {
          "type": "string",
          "pattern": "^[A-Z]{2}$",
          "description": "ISO 3166-1 alpha-2 country code where product is designed"
        }
      }
    },
    "assurances": {
      "type": "object",
      "properties": {
        "warranty": {
          "$ref": "#/definitions/warranty"
        },
        "return_policy": {
          "$ref": "#/definitions/return_policy"
        }
      }
    },
    "instructions": {
      "type": "object",
      "description": "Human-facing operational guidance for using and caring for the product",
      "properties": {
        "locale": {
          "type": "string",
          "pattern": "^[a-z]{2}-[A-Z]{2}$",
          "description": "BCP 47 locale code (e.g., en-US)"
        },
        "preparation": { "type": "string", "maxLength": 2000, "description": "Steps to ready the product before first use" },
        "installation": { "type": "string", "maxLength": 2000, "description": "Setup or assembly instructions" },
        "usage": { "type": "string", "maxLength": 2000, "description": "How to operate or use the product" },
        "application": { "type": "string", "maxLength": 2000, "description": "Surface, material, or context suitability" },
        "safety": { "type": "string", "maxLength": 2000, "description": "Safety warnings and precautions during use" },
        "storage": { "type": "string", "maxLength": 2000, "description": "How to store the product when not in use" },
        "cleaning": { "type": "string", "maxLength": 2000, "description": "How to clean or care for the product itself" },
        "maintenance": { "type": "string", "maxLength": 2000, "description": "Ongoing upkeep to extend product life" },
        "disposal": { "type": "string", "maxLength": 2000, "description": "End-of-life handling, recycling, or disposal guidance" },
        "clean_up": { "type": "string", "maxLength": 2000, "description": "How to clean tools or work area after use" }
      }
    },
    "warranty": {
      "type": "object",
      "properties": {
        "type": {
          "type": "string",
          "enum": ["standard", "extended"]
        },
        "duration": {
          "type": "object",
          "required": ["value", "unit"],
          "properties": {
            "value": {
              "type": "integer",
              "minimum": 1
            },
            "unit": {
              "type": "string",
              "enum": ["day", "month", "year"]
            }
          }
        },
        "scope": {
          "type": "string",
          "enum": ["limited", "full", "replacement only"]
        },
        "description": {
          "type": "string",
          "maxLength": 5000,
          "description": "Free-text warranty description, disclaimer, or legal prose"
        }
      }
    },
    "return_policy": {
      "type": "object",
      "properties": {
        "window_days": {
          "type": "integer",
          "minimum": 0,
          "maximum": 365
        },
        "free_return": {
          "type": "boolean"
        }
      }
    },
    "certification": {
      "type": "object",
      "required": ["type"],
      "properties": {
        "type": {
          "type": "string",
          "pattern": "^[A-Za-z][A-Za-z0-9 _./()\\-]{0,99}$",
          "minLength": 1,
          "maxLength": 100,
          "description": "Standard reference such as 'UL', 'UL Listed', 'ISO 11148-6', 'ATEX 2014/34/EU'. Accepts letters, digits, spaces, underscores, dots, slashes, parens, hyphens. Cannot contain commas or semicolons — those are list separators handled by the CSV mapper."
        },
        "number": {
          "type": "string",
          "minLength": 1,
          "maxLength": 100
        },
        "expiry_date": {
          "type": "string",
          "format": "date"
        },
        "document_url": {
          "type": "string",
          "format": "uri"
        }
      }
    },
    "variant": {
      "type": "object",
      "description": "Variant is a sparse override of product fields. Only include fields that differ from the parent product. All product fields can be overridden except id, brand_id, and classification.",
      "required": ["id", "product_id"],
      "properties": {
        "id": {
          "$ref": "#/definitions/uuid"
        },
        "product_id": {
          "$ref": "#/definitions/uuid",
          "description": "Reference to parent product. Variant inherits all product fields unless explicitly overridden."
        },
        "status": {
          "type": "string",
          "enum": ["draft", "active", "archived"],
          "description": "Optional - inherits from product if not specified"
        },
        "content": {
          "$ref": "#/definitions/content",
          "description": "Rarely overridden, but possible for variant-specific content"
        },
        "condition": {
          "type": "string",
          "enum": ["new", "used", "refurbished"],
          "description": "Optional - inherits from product if not specified"
        },
        "identifiers": {
          "type": "object",
          "description": "Only include identifiers that differ from product. SKU typically overridden for each variant.",
          "properties": {
            "sku": {
              "type": "string",
              "minLength": 1,
              "maxLength": 100
            },
            "gtin": {
              "type": "string",
              "pattern": "^\\d{8,14}$"
            },
            "upc": {
              "type": "string",
              "pattern": "^\\d{12}$"
            },
            "ean": {
              "type": "string",
              "pattern": "^\\d{13}$"
            },
            "mpn": {
              "type": "string",
              "maxLength": 100
            },
            "model_number": {
              "type": "string",
              "maxLength": 100
            },
            "usda_fdc_id": {
              "type": "string",
              "pattern": "^\\d+$",
              "description": "USDA FoodData Central database ID"
            },
            "asin": {
              "type": "string",
              "maxLength": 10,
              "pattern": "^[A-Z0-9]{10}$",
              "description": "Amazon Standard Identification Number (exactly 10 uppercase alphanumeric characters)"
            },
            "nsn": {
              "type": "string",
              "maxLength": 16,
              "pattern": "^[0-9A-Z]{4}-[0-9A-Z]{2}-[0-9A-Z]{3}-[0-9A-Z]{4}$|^[0-9A-Z][0-9A-Z-]{0,15}$",
              "description": "NATO Stock Number — hyphenated NATO form (e.g. 1234-56-789-1234) or local/alphanumeric form (e.g. 850519-S01)"
            }
          }
        },
        "channel_content": {
          "type": "object",
          "additionalProperties": { "$ref": "#/definitions/content" },
          "description": "Per-channel variant content variants, keyed by channel identifier. Each entry has the shape of `content` (all fields optional, extra keys allowed); sparse-override, deep-merged over variant `content` when a listing for that channel is created."
        },
        "attributes": { "$ref": "#/definitions/open_attributes" },
        "physical": {
          "$ref": "#/definitions/physical_specifications",
          "description": "Only include physical specs that differ from product (e.g., weight varies by size)"
        },
        "media_assets": {
          "$ref": "#/definitions/media_assets",
          "description": "Variant can override product media. Arrays replace (not merge)."
        },
        "compliance": {
          "$ref": "#/definitions/compliance"
        },
        "assurances": {
          "$ref": "#/definitions/assurances"
        },
        "instructions": {
          "$ref": "#/definitions/instructions"
        },
        "pricing": {
          "$ref": "#/definitions/pricing"
        },
        "relationships": {
          "type": "array",
          "items": { "$ref": "#/definitions/relationship" },
          "maxItems": 100
        },
        "brand_groupings": {
          "$ref": "#/definitions/brand_groupings"
        },
        "technical_data": {
          "type": "object",
          "description": "Measured/tested technical properties grouped by section name",
          "maxProperties": 20,
          "additionalProperties": {
            "type": "array",
            "maxItems": 100,
            "items": {
              "type": "object",
              "minProperties": 1,
              "additionalProperties": {
                "oneOf": [
                  { "type": "string" },
                  { "type": "number" },
                  { "type": "boolean" }
                ]
              }
            }
          }
        },
        "metadata": {
          "type": "object",
          "additionalProperties": true
        },
        "content_hash": {
          "type": ["string", "null"],
          "pattern": "^[a-f0-9]{64}$",
          "description": "SHA-256 hash of canonical JSON representation"
        }
      }
    },
    "physical_specifications": {
      "type": "object",
      "properties": {
        "weight": {
          "$ref": "#/definitions/weight_measurement"
        },
        "dimensions": {
          "$ref": "#/definitions/dimensions_measurement"
        },
        "package_weight": {
          "$ref": "#/definitions/weight_measurement"
        },
        "package_dimensions": {
          "$ref": "#/definitions/dimensions_measurement"
        }
      }
    },
    "weight_measurement": {
      "type": "object",
      "required": ["value", "unit"],
      "properties": {
        "value": {
          "type": "number",
          "minimum": 0
        },
        "unit": {
          "type": "string",
          "enum": ["lb", "kg", "g", "oz"]
        }
      }
    },
    "dimensions_measurement": {
      "type": "object",
      "required": ["length", "width", "height", "unit"],
      "properties": {
        "length": {
          "type": "number",
          "minimum": 0
        },
        "width": {
          "type": "number",
          "minimum": 0
        },
        "height": {
          "type": "number",
          "minimum": 0
        },
        "unit": {
          "type": "string",
          "enum": ["in", "cm", "mm", "ft", "m"]
        }
      }
    },
    "typed_attribute_value": {
      "type": "object",
      "description": "Open-attribute measurement value: a numeric value with a free-form unit of measure.",
      "required": ["value", "unit"],
      "properties": {
        "value": { "type": "number" },
        "unit":  { "type": "string", "minLength": 1, "maxLength": 32 }
      },
      "additionalProperties": false
    },
    "typed_attribute_range": {
      "type": "object",
      "description": "Open-attribute measurement range: numeric min and max with a free-form unit of measure.",
      "required": ["min", "max", "unit"],
      "properties": {
        "min":  { "type": "number" },
        "max":  { "type": "number" },
        "unit": { "type": "string", "minLength": 1, "maxLength": 32 }
      },
      "additionalProperties": false
    },
    "open_attribute_value": {
      "description": "Permitted value shapes for an open attribute: scalar, null, measurement {value,unit}, or range {min,max,unit}.",
      "oneOf": [
        { "type": "string", "maxLength": 100 },
        { "type": "number" },
        { "type": "boolean" },
        { "type": "null" },
        { "$ref": "#/definitions/typed_attribute_value" },
        { "$ref": "#/definitions/typed_attribute_range" }
      ]
    },
    "open_attributes": {
      "type": "object",
      "description": "Open attribute bag: five universal string attributes (color/size/material/finish/pattern) plus arbitrary additional attributes whose values follow open_attribute_value (scalar | {value,unit} | {min,max,unit} | null). e.g. processor_brand: 'intel', ram_gb: 16, weight_capacity: {value: 50, unit: 'kg'}.",
      "properties": {
        "color":    { "type": "string", "maxLength": 100 },
        "size":     { "type": "string", "maxLength": 100 },
        "material": { "type": "string", "maxLength": 100 },
        "finish":   { "type": "string", "maxLength": 100 },
        "pattern":  { "type": "string", "maxLength": 100 }
      },
      "additionalProperties": { "$ref": "#/definitions/open_attribute_value" }
    },
    "listing": {
      "type": "object",
      "required": ["id", "product_id", "channel", "channel_account_id", "status", "content"],
      "properties": {
        "id": {
          "$ref": "#/definitions/uuid"
        },
        "product_id": {
          "$ref": "#/definitions/uuid",
          "description": "Reference to the product this listing is for"
        },
        "brand_id": {
          "$ref": "#/definitions/uuid",
          "description": "Relationship FK to the brand entity. Mirrors product.brand_id; consumer connectors resolve brand data via brands/{brand_id}.json at sync time. Optional."
        },
        "channel": {
          "type": "string",
          "pattern": "^[a-z][a-z0-9_]{0,49}$",
          "minLength": 1,
          "maxLength": 50,
          "description": "Channel identifier. See config/schemas/registries/channels.json for known values."
        },
        "channel_account_id": {
          "type": "string",
          "minLength": 1,
          "maxLength": 100
        },
        "status": {
          "type": "string",
          "enum": ["draft", "pending", "active", "error", "delisted", "suspended"]
        },
        "content": {
          "allOf": [
            { "$ref": "#/definitions/content" },
            { "required": ["name"] }
          ]
        },
        "condition": {
          "type": "string",
          "enum": ["new", "used", "refurbished"],
          "description": "Optional - inherits from product if not specified"
        },
        "identifiers": {
          "type": "object",
          "description": "Channel-level identifier overrides",
          "properties": {
            "sku": {
              "type": "string",
              "minLength": 1,
              "maxLength": 100
            },
            "gtin": {
              "type": "string",
              "pattern": "^\\d{8,14}$"
            },
            "upc": {
              "type": "string",
              "pattern": "^\\d{12}$"
            },
            "ean": {
              "type": "string",
              "pattern": "^\\d{13}$"
            },
            "mpn": {
              "type": "string",
              "maxLength": 100
            },
            "model_number": {
              "type": "string",
              "maxLength": 100
            },
            "usda_fdc_id": {
              "type": "string",
              "pattern": "^\\d+$"
            },
            "asin": {
              "type": "string",
              "maxLength": 10,
              "pattern": "^[A-Z0-9]{10}$",
              "description": "Amazon Standard Identification Number (exactly 10 uppercase alphanumeric characters)"
            },
            "nsn": {
              "type": "string",
              "maxLength": 16,
              "pattern": "^[0-9A-Z]{4}-[0-9A-Z]{2}-[0-9A-Z]{3}-[0-9A-Z]{4}$|^[0-9A-Z][0-9A-Z-]{0,15}$",
              "description": "NATO Stock Number — hyphenated NATO form (e.g. 1234-56-789-1234) or local/alphanumeric form (e.g. 850519-S01)"
            }
          }
        },
        "classification": {
          "type": "object",
          "description": "Channel-level classification overrides",
          "properties": {
            "primary_category": {
              "type": "string",
              "minLength": 1,
              "maxLength": 500
            },
            "product_type": {
              "type": "string",
              "minLength": 1,
              "maxLength": 255
            },
            "tags": {
              "type": "array",
              "items": {
                "type": "string",
                "minLength": 1,
                "maxLength": 50
              },
              "maxItems": 50
            },
            "external_codes": {
              "type": "object",
              "properties": {
                "unspsc": {
                  "type": "string",
                  "pattern": "^\\d{8}$"
                },
                "eclass": {
                  "type": "string",
                  "pattern": "^\\d{8}$"
                },
                "etim": {
                  "type": "string",
                  "pattern": "^EC\\d{6}$"
                }
              }
            }
          }
        },
        "attributes": { "$ref": "#/definitions/open_attributes" },
        "physical": {
          "$ref": "#/definitions/physical_specifications"
        },
        "media_assets": {
          "$ref": "#/definitions/media_assets"
        },
        "compliance": {
          "$ref": "#/definitions/compliance"
        },
        "assurances": {
          "$ref": "#/definitions/assurances"
        },
        "instructions": {
          "$ref": "#/definitions/instructions"
        },
        "pricing": {
          "$ref": "#/definitions/pricing"
        },
        "availability": {
          "$ref": "#/definitions/availability"
        },
        "shipping": {
          "$ref": "#/definitions/shipping"
        },
        "relationships": {
          "type": "array",
          "items": { "$ref": "#/definitions/relationship" },
          "maxItems": 50
        },
        "recommendations": {
          "type": "array",
          "items": { "$ref": "#/definitions/recommendation" },
          "maxItems": 50
        },
        "brand_groupings": {
          "$ref": "#/definitions/brand_groupings"
        },
        "technical_data": {
          "type": "object",
          "description": "Technical specifications",
          "additionalProperties": true
        },
        "metadata": {
          "type": "object",
          "additionalProperties": true
        },
        "syndication": {
          "$ref": "#/definitions/syndication_metadata"
        },
        "content_hash": {
          "type": ["string", "null"],
          "pattern": "^[a-f0-9]{64}$",
          "description": "SHA-256 hash of canonical JSON representation"
        },
        "variants": {
          "type": "array",
          "description": "Variant-level listing details. Each entry is a sparse override of listing-level defaults.",
          "items": {
            "type": "object",
            "required": ["variant_id"],
            "properties": {
              "variant_id": {
                "$ref": "#/definitions/uuid",
                "description": "Reference to the variant in the product"
              },
              "status": {
                "type": "string",
                "enum": ["draft", "pending", "active", "error", "delisted", "suspended"]
              },
              "condition": {
                "type": "string",
                "enum": ["new", "used", "refurbished"]
              },
              "identifiers": {
                "type": "object",
                "properties": {
                  "sku": {
                    "type": "string",
                    "minLength": 1,
                    "maxLength": 100
                  },
                  "gtin": {
                    "type": "string",
                    "pattern": "^\\d{8,14}$"
                  },
                  "upc": {
                    "type": "string",
                    "pattern": "^\\d{12}$"
                  },
                  "ean": {
                    "type": "string",
                    "pattern": "^\\d{13}$"
                  },
                  "mpn": {
                    "type": "string",
                    "maxLength": 100
                  },
                  "model_number": {
                    "type": "string",
                    "maxLength": 100
                  },
                  "usda_fdc_id": {
                    "type": "string",
                    "pattern": "^\\d+$"
                  },
                  "asin": {
                    "type": "string",
                    "maxLength": 10,
                    "pattern": "^[A-Z0-9]{10}$",
                    "description": "Amazon Standard Identification Number (exactly 10 uppercase alphanumeric characters)"
                  },
                  "nsn": {
                    "type": "string",
                    "maxLength": 16,
                    "pattern": "^[0-9A-Z]{4}-[0-9A-Z]{2}-[0-9A-Z]{3}-[0-9A-Z]{4}$|^[0-9A-Z][0-9A-Z-]{0,15}$",
                    "description": "NATO Stock Number — hyphenated NATO form (e.g. 1234-56-789-1234) or local/alphanumeric form (e.g. 850519-S01)"
                  }
                }
              },
              "classification": {
                "type": "object",
                "properties": {
                  "primary_category": {
                    "type": "string",
                    "minLength": 1,
                    "maxLength": 500
                  },
                  "product_type": {
                    "type": "string",
                    "minLength": 1,
                    "maxLength": 255
                  },
                  "tags": {
                    "type": "array",
                    "items": {
                      "type": "string",
                      "minLength": 1,
                      "maxLength": 50
                    },
                    "maxItems": 50
                  }
                }
              },
              "content": {
                "$ref": "#/definitions/content"
              },
              "attributes": { "$ref": "#/definitions/open_attributes" },
              "physical": {
                "$ref": "#/definitions/physical_specifications"
              },
              "media_assets": {
                "$ref": "#/definitions/media_assets"
              },
              "compliance": {
                "$ref": "#/definitions/compliance"
              },
              "assurances": {
                "$ref": "#/definitions/assurances"
              },
              "instructions": {
                "$ref": "#/definitions/instructions"
              },
              "relationships": {
                "type": "array",
                "items": { "$ref": "#/definitions/relationship" }
              },
              "brand_groupings": {
                "$ref": "#/definitions/brand_groupings"
              },
              "technical_data": {
                "type": "object",
                "additionalProperties": true
              },
              "pricing": {
                "$ref": "#/definitions/pricing"
              },
              "availability": {
                "$ref": "#/definitions/availability"
              },
              "shipping": {
                "$ref": "#/definitions/shipping"
              },
              "metadata": {
                "type": "object",
                "additionalProperties": true
              }
            }
          }
        },
        "access_control": {
          "$ref": "#/definitions/access_control"
        }
      }
    },
    "content": {
      "type": "object",
      "properties": {
        "name": {
          "type": "string",
          "minLength": 1,
          "maxLength": 255
        },
        "description_short": {
          "type": "string",
          "minLength": 1,
          "maxLength": 500
        },
        "description_long": {
          "type": "string",
          "maxLength": 50000
        },
        "features": {
          "type": "array",
          "items": {
            "type": "string",
            "minLength": 1,
            "maxLength": 255
          },
          "maxItems": 20
        },
        "keywords": {
          "type": "array",
          "items": {
            "type": "string",
            "minLength": 1,
            "maxLength": 50
          },
          "maxItems": 50
        },
        "model_name": {
          "type": "string",
          "maxLength": 100,
          "description": "Buyer-facing marketing/series model name (e.g. Amazon model_name 'W3000 Series 20V Impact Wrench'). Distinct from content.name (full title) and identifiers.model_number/mpn (part number). Optional; not added to any required set."
        },
        "seo_title": {
          "type": "string",
          "minLength": 1,
          "maxLength": 255,
          "description": "SEO/meta title for search engines and channel listing pages. Optional; not added to any required set."
        },
        "seo_description": {
          "type": "string",
          "minLength": 1,
          "maxLength": 500,
          "description": "SEO/meta description for search engines and channel listing pages. Optional; not added to any required set."
        },
        "locale": {
          "type": "string",
          "pattern": "^[a-z]{2}-[A-Z]{2}$",
          "default": "en-US",
          "description": "Locale code for this content (e.g., en-US, fr-CA)"
        }
      }
    },
    "pricing": {
      "type": "object",
      "required": ["currency"],
      "properties": {
        "currency": {
          "type": "string",
          "pattern": "^[A-Z]{3}$"
        },
        "list_price": {
          "type": "number",
          "minimum": 0,
          "multipleOf": 0.01
        },
        "sale_price": {
          "type": "number",
          "minimum": 0,
          "multipleOf": 0.01
        },
        "map_price": {
          "type": "number",
          "minimum": 0,
          "multipleOf": 0.01
        },
        "msrp": {
          "type": "number",
          "minimum": 0,
          "multipleOf": 0.01
        },
        "cost": {
          "type": "number",
          "minimum": 0,
          "multipleOf": 0.01
        },
        "tier_pricing": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/tier_price"
          },
          "maxItems": 10
        },
        "promotional_pricing": {
          "$ref": "#/definitions/promotional_pricing"
        }
      }
    },
    "tier_price": {
      "type": "object",
      "required": ["min_quantity", "price"],
      "properties": {
        "min_quantity": {
          "type": "integer",
          "minimum": 1
        },
        "price": {
          "type": "number",
          "minimum": 0,
          "multipleOf": 0.01
        }
      }
    },
    "promotional_pricing": {
      "type": "object",
      "required": ["price", "start_date", "end_date"],
      "properties": {
        "price": {
          "type": "number",
          "minimum": 0,
          "multipleOf": 0.01
        },
        "start_date": {
          "type": "string",
          "format": "date-time"
        },
        "end_date": {
          "type": "string",
          "format": "date-time"
        },
        "promo_code": {
          "type": "string",
          "maxLength": 50
        }
      }
    },
    "availability": {
      "type": "object",
      "properties": {
        "inventory_tracking": {
          "type": "boolean"
        },
        "inventory_quantity": {
          "type": "integer",
          "minimum": 0
        },
        "inventory_policy": {
          "type": "string",
          "enum": ["track", "dont track", "continue selling"]
        },
        "fulfillment_method": {
          "type": "string",
          "enum": ["merchant", "fba", "wfs", "dropship", "sfs", "3pl"]
        },
        "fulfillment_latency": {
          "type": "integer",
          "minimum": 0,
          "maximum": 30
        },
        "restock_date": {
          "type": "string",
          "format": "date"
        },
        "preorder": {
          "$ref": "#/definitions/preorder"
        }
      }
    },
    "preorder": {
      "type": "object",
      "required": ["enabled"],
      "properties": {
        "enabled": {
          "type": "boolean"
        },
        "availability_date": {
          "type": "string",
          "format": "date"
        },
        "message": {
          "type": "string",
          "maxLength": 255
        }
      }
    },
    "shipping": {
      "type": "object",
      "properties": {
        "free_shipping": {
          "type": "boolean"
        },
        "shipping_class": {
          "type": "string",
          "maxLength": 100
        },
        "excluded_regions": {
          "type": "array",
          "items": {
            "type": "string",
            "pattern": "^[A-Z]{2}(-[A-Z0-9]+)?$"
          }
        },
        "expedited_available": {
          "type": "boolean"
        },
        "white_glove_available": {
          "type": "boolean"
        }
      }
    },
    "access_control": {
      "type": "object",
      "required": ["visibility"],
      "properties": {
        "visibility": {
          "type": "string",
          "enum": ["public", "private", "restricted"]
        },
        "authorized_partners": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "embargo_until": {
          "type": "string",
          "format": "date-time"
        },
        "geographic_restrictions": {
          "type": "array",
          "items": {
            "type": "string",
            "pattern": "^[A-Z]{2}$"
          }
        },
        "usage_rights": {
          "$ref": "#/definitions/usage_rights"
        }
      }
    },
    "usage_rights": {
      "type": "object",
      "properties": {
        "can_modify_price": {
          "type": "boolean"
        },
        "can_modify_content": {
          "type": "boolean"
        },
        "can_use_enhanced_content": {
          "type": "boolean"
        },
        "can_resyndicate": {
          "type": "boolean"
        },
        "price_floor": {
          "type": "number",
          "minimum": 0,
          "multipleOf": 0.01
        },
        "price_ceiling": {
          "type": "number",
          "minimum": 0,
          "multipleOf": 0.01
        }
      }
    },
    "syndication_metadata": {
      "type": "object",
      "properties": {
        "last_pushed": {
          "type": "string",
          "format": "date-time"
        },
        "last_success": {
          "type": "string",
          "format": "date-time"
        },
        "last_error": {
          "$ref": "#/definitions/syndication_error"
        },
        "validation_status": {
          "type": "string",
          "enum": ["valid", "invalid", "warnings"]
        },
        "validation_errors": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/validation_error"
          }
        },
        "channel_item_id": {
          "type": "string",
          "maxLength": 255
        },
        "channel_url": {
          "type": "string",
          "format": "uri"
        },
        "performance_metrics": {
          "$ref": "#/definitions/performance_metrics"
        }
      }
    },
    "syndication_error": {
      "type": "object",
      "required": ["timestamp", "code", "message"],
      "properties": {
        "timestamp": {
          "type": "string",
          "format": "date-time"
        },
        "code": {
          "type": "string",
          "maxLength": 50
        },
        "message": {
          "type": "string",
          "maxLength": 1000
        },
        "details": {
          "type": "object"
        }
      }
    },
    "validation_error": {
      "type": "object",
      "required": ["field", "error", "severity"],
      "properties": {
        "field": {
          "type": "string",
          "maxLength": 255
        },
        "error": {
          "type": "string",
          "maxLength": 500
        },
        "severity": {
          "type": "string",
          "enum": ["error", "warning", "info"]
        }
      }
    },
    "performance_metrics": {
      "type": "object",
      "properties": {
        "views": {
          "type": "integer",
          "minimum": 0
        },
        "clicks": {
          "type": "integer",
          "minimum": 0
        },
        "conversions": {
          "type": "integer",
          "minimum": 0
        },
        "revenue": {
          "type": "number",
          "minimum": 0,
          "multipleOf": 0.01
        }
      }
    },
    "relationship_type": {
      "type": "string",
      "enum": ["compatible with", "fits", "replacement for", "works with", "designed for", "requires", "includes", "accessory for"]
    },
    "relationship_target": {
      "type": "object",
      "properties": {
        "product_id": { "type": "string", "format": "uuid" },
        "sku": { "type": "string", "maxLength": 100 },
        "gtin": { "type": "string", "pattern": "^[0-9]{8,14}$" },
        "upc": { "type": "string", "pattern": "^[0-9]{12}$" },
        "ean": { "type": "string", "pattern": "^[0-9]{13}$" },
        "mpn": { "type": "string", "maxLength": 100 },
        "model_number": { "type": "string", "maxLength": 100 },
        "usda_fdc_id": { "type": "string", "maxLength": 20 },
        "brand": { "type": "string", "maxLength": 255 },
        "name": { "type": "string", "maxLength": 255 }
      },
      "anyOf": [
        { "required": ["product_id"] },
        { "required": ["sku"] },
        { "required": ["gtin"] },
        { "required": ["upc"] },
        { "required": ["ean"] },
        { "required": ["mpn"] },
        { "required": ["model_number"] },
        { "required": ["usda_fdc_id"] },
        { "required": ["name"] }
      ]
    },
    "relationship": {
      "type": "object",
      "required": ["type", "target"],
      "properties": {
        "type": { "$ref": "#/definitions/relationship_type" },
        "target": { "$ref": "#/definitions/relationship_target" },
        "note": { "type": "string", "maxLength": 500 }
      }
    },
    "recommendation_type": {
      "type": "string",
      "enum": ["upsell", "cross sell", "frequently bought together", "customers also bought", "recommended", "bundle", "substitute", "similar to", "compare to", "alternative to"]
    },
    "recommendation": {
      "type": "object",
      "required": ["type", "target"],
      "properties": {
        "type": { "$ref": "#/definitions/recommendation_type" },
        "target": { "$ref": "#/definitions/relationship_target" },
        "score": { "type": "number", "minimum": 0.0, "maximum": 1.0 },
        "source": { "type": "string", "maxLength": 100 },
        "window": { "type": "string", "maxLength": 50 },
        "generated_at": { "type": "string", "format": "date-time" }
      }
    },
    "brand_groupings": {
      "type": "object",
      "properties": {
        "product_line": { "type": "string", "minLength": 1, "maxLength": 255, "description": "Primary brand product family" },
        "series": { "type": "string", "minLength": 1, "maxLength": 255, "description": "Sub-family within a product line" },
        "collection": { "type": "array", "items": { "type": "string", "minLength": 1, "maxLength": 255 }, "minItems": 1, "maxItems": 20, "description": "Curated or seasonal grouping(s)" },
        "sub_brand": { "type": "string", "minLength": 1, "maxLength": 255, "description": "Distinct brand identity within parent brand" },
        "platform": { "type": "array", "items": { "type": "string", "minLength": 1, "maxLength": 255 }, "minItems": 1, "maxItems": 10, "description": "Shared technology or compatibility ecosystem(s)" },
        "generation": { "type": "string", "minLength": 1, "maxLength": 255, "description": "Version or iteration of a product line" },
        "edition": { "type": "string", "minLength": 1, "maxLength": 255, "description": "Special variant or limited release" }
      },
      "additionalProperties": false
    },
    "signature": {
      "type": "object",
      "required": ["key_ref", "algorithm", "value", "signed_at"],
      "properties": {
        "key_ref": {
          "type": "string",
          "pattern": "^\\.openpx/keys/[a-z0-9_-]+-\\d{4}-\\d{2}-\\d{2}\\.pub$",
          "description": "Path to public key file in repo (e.g., .openpx/keys/org-2025-06-15.pub)"
        },
        "algorithm": {
          "type": "string",
          "enum": ["Ed25519"],
          "description": "Signing algorithm"
        },
        "value": {
          "type": "string",
          "description": "Base64-encoded Ed25519 signature"
        },
        "signed_at": {
          "type": "string",
          "format": "date-time",
          "description": "ISO 8601 timestamp of when the entity was signed"
        }
      },
      "additionalProperties": false
    }
  }
}