> ## Documentation Index > Fetch the complete documentation index at: https://docs.voltview.co.uk/llms.txt > Use this file to discover all available pages before exploring further. # Validate invoice > Validates an invoice against contract data and optional user-provided consumption data. Performs comprehensive validation including consumption matching, meter reading verification, and check against contract. **Validation Rules:** - Meter Reading Logic: Current reading must be ≥ previous reading - Contract Matching: Invoice date must fall within contract period - MPAN Matching: At least one MPAN must match between invoice and contract **Data Sources:** - Manual uploads from parseInvoice endpoint - Invoices from Supplier Integration system - User-provided consumption and meter reading data ## OpenAPI ````yaml post /v1/billValidation/validateInvoice openapi: 3.0.3 info: title: VoltView API description: >- The VoltView API provides comprehensive energy monitoring and management capabilities for multi-site businesses, enabling real-time tracking of energy consumption, cost analysis, and environmental impact metrics. Our API suite includes: - Site Management API - Manage and monitor multiple site locations - Energy Consumption API - Access detailed energy usage data - Cost Analysis API - Track and analyse energy costs - Environmental Metrics API - Monitor carbon emissions and energy efficiency - Bill Validation API - Validate and audit utility bills for accuracy - Supplier Integration API - Integrate with utility suppliers for automated data collection ## Getting started guide To start using the VoltView API, you need to: - Sign up for a VoltView account to receive your API credentials - Review our data granularity options (hourly/daily/monthly) - Ensure your requests are sent via HTTPS - All responses are returned in JSON format ## Authentication Include your VoltView API key in the `x-api-key` header on every request. ### Authentication error response If authentication fails, you will receive an HTTP 401 Unauthorised response with a detailed error message in the JSON response body. ## Data Units - Energy Consumption: kWh - Power Demand: kW - Carbon Emissions: kg CO2e/tonnes CO2e - Currency: GBP (£) - Time Series: ISO 8601 format - Numeric Values: Rounded to 2 decimal places version: 1.0.0 contact: email: info@voltview.co.uk license: name: Proprietary servers: - url: https://api.voltview.co.uk description: Production server security: - apiKeyAuth: [] tags: - name: Authentication description: Endpoints for authentication - name: User description: User profile management - name: Sites description: Multi-site management endpoints - name: Energy Consumption description: Energy consumption data endpoints - name: Specific Site description: Operations for specific sites - name: Meters description: Meter lookup and meter readings management - name: Emissions description: Carbon emissions data endpoints - name: LOA Management description: >- Letter of Authority (LOA) management - create, list, view, and update status of LOAs - name: Supplier Integration description: Utilities integration endpoints - name: Billing Insights description: Account-level billing insights and bill assurance opportunities - name: Bill Validation description: Utility bill validation and error detection endpoints paths: /v1/billValidation/validateInvoice: post: tags: - Bill Validation summary: Validate invoice description: >- Validates an invoice against contract data and optional user-provided consumption data. Performs comprehensive validation including consumption matching, meter reading verification, and check against contract. **Validation Rules:** - Meter Reading Logic: Current reading must be ≥ previous reading - Contract Matching: Invoice date must fall within contract period - MPAN Matching: At least one MPAN must match between invoice and contract **Data Sources:** - Manual uploads from parseInvoice endpoint - Invoices from Supplier Integration system - User-provided consumption and meter reading data operationId: validateInvoice requestBody: required: true content: application/json: schema: type: object properties: filePath: type: string description: >- File path to the invoice document to validate. Can be from a manually uploaded invoice (parseInvoice endpoint) or from an invoice retrieved via Supplier Integration endpoints. example: accounts/123456789/invoices/INV2024001.pdf userConsumptionData: type: object description: >- Optional user-provided consumption data to validate against the invoice properties: fromDate: type: string format: date-time description: Start date of consumption period (ISO 8601) example: '2024-06-01T00:00:00.000Z' toDate: type: string format: date-time description: End date of consumption period (ISO 8601) example: '2024-07-01T00:00:00.000Z' utilityType: type: string enum: - ELECTRICITY - GAS - BMS description: Type of utility consumption: type: object description: Consumption values for the period properties: activeImportKwh: type: number description: Active energy imported (main consumption) in kWh example: 5223 activeExportKwh: type: number description: >- Active energy exported in kWh (for sites with generation) dayConsumption: type: number description: Day/peak consumption in kWh (for dual-rate tariffs) nightConsumption: type: number description: >- Night/off-peak consumption in kWh (for dual-rate tariffs) reactiveImportKvarh: type: number description: Reactive energy imported in kvarh (electricity only) reactiveExportKvarh: type: number description: Reactive energy exported in kvarh (electricity only) apparentKvah: type: number description: >- Apparent energy consumption in kVAh (electricity only) meterReadings: type: object description: Optional meter reading information properties: previousReading: type: number description: Previous meter reading example: 100000 currentReading: type: number description: Current meter reading example: 105223 previousReadingDate: type: string format: date-time description: Date of previous reading (ISO 8601) example: '2024-06-01T00:00:00.000Z' currentReadingDate: type: string format: date-time description: Date of current reading (ISO 8601) example: '2024-07-01T00:00:00.000Z' previousReadingType: type: string enum: - actual - estimated - customer - smart description: Type of previous reading currentReadingType: type: string enum: - actual - estimated - customer - smart description: Type of current reading required: - filePath examples: basicValidation: summary: Basic validation without user data value: filePath: accounts/123456789/invoices/INV2024001.pdf withConsumptionData: summary: Validation with consumption data value: filePath: accounts/123456789/invoices/INV2024001.pdf userConsumptionData: utilityType: ELECTRICITY consumption: activeImportKwh: 5223 withMeterReadings: summary: Validation with meter readings value: filePath: accounts/123456789/invoices/INV2024001.pdf userConsumptionData: utilityType: ELECTRICITY meterReadings: previousReading: 100000 currentReading: 105223 previousReadingDate: '2024-06-01T00:00:00.000Z' currentReadingDate: '2024-07-01T00:00:00.000Z' previousReadingType: actual currentReadingType: actual responses: '200': description: Validation completed - may return passed, failed, or pending status content: application/json: schema: $ref: '#/components/schemas/ValidationResult' examples: validationPassed: summary: Validation Passed value: filePath: accounts/123456789/invoices/INV2024001.pdf status: passed errors: [] validationFailedSingle: summary: Validation Failed - Single Error value: filePath: accounts/123456789/invoices/INV2024001.pdf status: failed errors: - type: consumptionMismatch description: >- Invoice consumption differs from user-provided consumption expected: 6000 kWh actual: 5223 kWh validationFailedMultiple: summary: Validation Failed - Multiple Errors value: filePath: accounts/123456789/invoices/INV2024001.pdf status: failed errors: - type: consumptionMismatch description: >- Invoice consumption differs from user-provided consumption expected: 6000 kWh actual: 5223 kWh - type: consumptionMismatch description: >- Invoice consumption differs from calculated consumption based on meter readings expected: 6033 kWh actual: 5223 kWh - type: rateMismatch description: Unit rate differs from contract rate expected: 25.50p/kWh actual: 28.87p/kWh validationPending: summary: Validation Pending - No Contract value: filePath: accounts/123456789/invoices/INV2024001.pdf status: pending errors: - type: other description: >- Cannot validate - please parse a contract document for the corresponding MPAN and date range expected: Contract document with matching MPAN and date range actual: No contract document found '400': description: Bad Request - Invalid input content: application/json: schema: $ref: '#/components/schemas/Error' examples: missingFilePath: summary: Missing filePath value: error: File path is required invalidConsumptionData: summary: Invalid consumption data value: error: User-provided consumption cannot be negative '401': description: Unauthorized - Authentication required content: application/json: schema: $ref: '#/components/schemas/Error' example: error: Unauthorized '404': description: Not Found - Invoice not found content: application/json: schema: $ref: '#/components/schemas/Error' example: error: Invoice not found at specified file path components: schemas: ValidationResult: type: object properties: filePath: type: string description: File path to the validated invoice document status: type: string enum: - passed - failed - pending description: >- Validation status - passed means all validations succeeded, failed means discrepancies were found, pending means validation could not be completed (e.g., missing contract data) errors: type: array items: type: object properties: type: type: string enum: - consumptionMismatch - rateMismatch - standingChargeError - dayRateMismatch - nightRateMismatch - capacityChargeError - vatError - cclError - dateMismatch - other description: Type of validation error detected description: type: string description: Human-readable description of the validation error expected: type: string description: Expected value or condition actual: type: string description: Actual value found that caused the validation error description: >- Array of validation errors found. Empty array indicates validation passed. Error: type: object properties: type: type: string enum: - error description: Error type indicator error: type: object properties: type: type: string enum: - invalid_request_error description: Specific error type message: type: string description: Human-readable error message securitySchemes: apiKeyAuth: type: apiKey in: header name: x-api-key description: VoltView API key ````