{
  "openapi": "3.1.0",
  "info": {
    "title": "Andrew Gilliland API",
    "version": "1.0.0",
    "description": "Public machine-readable endpoints provided by andrewgilliland.dev."
  },
  "servers": [
    {
      "url": "https://andrewgilliland.dev"
    }
  ],
  "paths": {
    "/api/county-population.json": {
      "get": {
        "summary": "Get county population estimates",
        "description": "Returns 2023 population estimates for United States counties, keyed by five-digit county FIPS code.",
        "operationId": "getCountyPopulationEstimates",
        "responses": {
          "200": {
            "description": "County population estimates",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/CountyPopulationResponse"
                }
              }
            }
          },
          "502": {
            "description": "The upstream Census dataset could not be loaded or parsed",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/ErrorResponse"
                }
              }
            }
          }
        }
      }
    }
  },
  "components": {
    "schemas": {
      "CountyPopulationResponse": {
        "type": "object",
        "required": ["source", "counties"],
        "properties": {
          "source": {
            "type": "string",
            "examples": [
              "U.S. Census Bureau Population Estimates Program (2023)"
            ]
          },
          "counties": {
            "type": "object",
            "description": "County records keyed by five-digit county FIPS code.",
            "additionalProperties": {
              "$ref": "#/components/schemas/CountyPopulation"
            }
          }
        }
      },
      "CountyPopulation": {
        "type": "object",
        "required": ["stateId", "name", "population"],
        "properties": {
          "stateId": {
            "type": "string",
            "pattern": "^[0-9]{2}$",
            "description": "Two-digit state FIPS code."
          },
          "name": {
            "type": "string",
            "description": "County and state name."
          },
          "population": {
            "type": "integer",
            "minimum": 1
          }
        }
      },
      "ErrorResponse": {
        "type": "object",
        "required": ["error"],
        "properties": {
          "error": {
            "type": "string"
          }
        }
      }
    }
  }
}