{
  "openapi": "3.1.0",
  "info": {
    "title": "Income Tax Calculation and Reporting API",
    "description": "Computes tax due and quarterly reporting figures from income, deductions and jurisdiction. Pre-launch design; endpoints are not live yet.",
    "version": "0.1.0",
    "x-planned-pricing": {
      "model": "free tier for evaluation, paid tiers by volume",
      "status": "planned; nothing charged before launch"
    }
  },
  "servers": [
    {
      "url": "https://openapiregistry.com/api/v1/income-tax-calculator",
      "description": "Pre-launch: endpoints are not live yet and answer 503."
    }
  ],
  "security": [
    {
      "ApiKeyAuth": []
    }
  ],
  "paths": {
    "/calculations": {
      "post": {
        "summary": "Calculate tax due",
        "description": "Returns computed tax due and quarterly reporting figures for an individual or business based on the supplied income, deductions and jurisdiction.",
        "tags": [
          "finance/compliance"
        ],
        "operationId": "income-tax-calculator-post-calculations",
        "requestBody": {
          "required": true,
          "description": "The income and jurisdiction details to calculate tax on.",
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "properties": {
                  "jurisdiction": {
                    "type": "string",
                    "description": "The tax jurisdiction and filing regime, for example US-FEDERAL."
                  },
                  "filing_status": {
                    "type": "string",
                    "description": "Filing status for an individual, for example single or married-filing-jointly."
                  },
                  "gross_income": {
                    "type": "number",
                    "description": "Gross income in the reporting currency."
                  },
                  "deductions": {
                    "type": "number",
                    "description": "Claimed deductions to subtract before tax is computed."
                  },
                  "tax_year": {
                    "type": "integer",
                    "description": "The tax year the calculation applies to."
                  }
                }
              },
              "example": {
                "jurisdiction": "US-FEDERAL",
                "filing_status": "single",
                "gross_income": 75000,
                "deductions": 13500,
                "tax_year": 2026
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Tax calculation returned.",
            "content": {
              "application/json": {
                "example": {
                  "tax_due": 8450.0,
                  "effective_rate": 0.1127,
                  "quarterly": [
                    {
                      "period": "Q1",
                      "payment": 2112.5
                    }
                  ]
                },
                "schema": {
                  "type": "object"
                }
              }
            }
          },
          "400": {
            "description": "Missing or invalid income, deductions or jurisdiction."
          },
          "503": {
            "description": "Pre-launch: endpoints are not live yet."
          }
        }
      }
    }
  },
  "components": {
    "securitySchemes": {
      "ApiKeyAuth": {
        "type": "apiKey",
        "in": "header",
        "name": "X-API-Key",
        "description": "Planned for launch: an API key issued on request. Free tier for evaluation, paid tiers by volume; nothing is charged before launch."
      }
    }
  }
}