{
  "openapi": "3.0.0",
  "info": { "title": "Protocol E2E Catalog API", "version": "1.0.0" },
  "paths": {
    "/api/products": {
      "get": {
        "tags": ["Catalog"],
        "operationId": "listProducts",
        "responses": {
          "200": {
            "description": "All products",
            "content": {
              "application/json": {
                "schema": { "type": "array", "items": { "$ref": "#/components/schemas/Product" } }
              }
            }
          }
        }
      }
    },
    "/api/products/{id}": {
      "get": {
        "tags": ["Catalog"],
        "operationId": "getProduct",
        "parameters": [
          { "name": "id", "in": "path", "required": true, "schema": { "type": "integer", "format": "int64" } }
        ],
        "responses": {
          "200": {
            "description": "A product",
            "content": {
              "application/json": { "schema": { "$ref": "#/components/schemas/Product" } }
            }
          }
        }
      }
    },
    "/api/products/category/{category}": {
      "get": {
        "tags": ["Catalog"],
        "operationId": "getProductsByCategory",
        "parameters": [
          { "name": "category", "in": "path", "required": true, "schema": { "$ref": "#/components/schemas/Category" } }
        ],
        "responses": {
          "200": {
            "description": "Products in a category",
            "content": {
              "application/json": {
                "schema": { "type": "array", "items": { "$ref": "#/components/schemas/Product" } }
              }
            }
          }
        }
      }
    }
  },
  "components": {
    "schemas": {
      "Category": {
        "type": "string",
        "enum": ["BOOKS", "ELECTRONICS", "TOYS"]
      },
      "Dimensions": {
        "type": "object",
        "properties": {
          "width": { "type": "number", "format": "double" },
          "height": { "type": "number", "format": "double" }
        }
      },
      "Product": {
        "type": "object",
        "properties": {
          "id": { "type": "integer", "format": "int64" },
          "name": { "type": "string" },
          "category": { "$ref": "#/components/schemas/Category" },
          "tags": { "type": "array", "items": { "type": "string" } },
          "rating": { "type": "number", "format": "double" },
          "dimensions": { "$ref": "#/components/schemas/Dimensions" }
        }
      }
    }
  }
}