> ## Documentation Index > Fetch the complete documentation index at: https://docs.paygentic.io/llms.txt > Use this file to discover all available pages before exploring further. # Create > Create a new metered cost for a product. ## OpenAPI ````yaml /openapi.json post /v0/costs openapi: 3.1.0 info: title: Paygentic API version: 0.1.0 description: > The Paygentic API provides a comprehensive platform for building and scaling monetization infrastructure. ## Authentication All API requests require authentication using an API key passed in the `Authorization` header: ``` Authorization: Bearer YOUR_API_KEY ``` ## Base URL All API requests should be made to: ``` https://api.paygentic.io/v0 ``` contact: name: Paygentic Support email: support@paygentic.io license: name: Proprietary servers: - url: https://api.paygentic.io description: Production API - url: https://api.sandbox.paygentic.io description: Sandbox API security: - BearerAuth: [] tags: - name: Customers description: >- A `Customer` is an entity connected to a `Merchant` via a `Subscription`. This represents the merchant-facing perspective of `Consumers` who purchase their `Products`. - name: Billable Metrics description: >- A `Billable Metric` defines a measurable quantity tied to a `Product`'s consumption. Each metric stores details including its label, an explanatory description, and measurement units. - name: Grants description: >- Grants credit a customer's metered entitlement balance. Merchants can create grants directly or void existing ones. Use `GET /v1/entitlements?customerId={id}` or `GET /v1/entitlements?subscriptionId={id}` to find the metered entitlement `id` needed for these endpoints. - name: Features description: >- A `Feature` represents a specific capability or functionality provided by a `Product`. Features can be metered (usage-based), static (fixed allocation), or boolean (enabled/disabled). - name: Fees description: >- A `Fee` defines a recurring or one-time charge tied to a `Product`. Fees are linked to prices, and cadence is defined on the Price. - name: Plans description: >- A `Plan` links a collection of `Prices` to a `Product`. It functions as a pricing structure document for a particular feature set or service offering. - name: Prices description: >- A `Price` determines the monetary value for a single unit of a `Billable Metric`. Prices are exclusively grouped within a `Plan`. - name: Products description: >- A `Product` is an offering sold by a `Merchant`. It includes product metadata like title, summary, and pricing details. `Plans`, `Prices`, and `Subscriptions` are all associated with products. - name: Sources description: >- A `Source` is an external data provider capable of automatically creating usage events. Configuration occurs at the plan level, enabling data retrieval from third-party platforms such as Stripe to produce billable events. - name: Subscriptions description: >- A `Subscription` is a customer's commitment to purchase a `Product` following the terms of a `Plan` and its linked `Prices`. - name: Users description: >- A `User` is an entity granted access to an Organization's resources. All operations are performed by users. - name: Invoices V2 description: >- Invoice V2 operations supporting billing cycles organized by time periods. Warning: v0 invoice endpoints are no longer supported. - name: Revenue description: Revenue data from invoices and payments - name: Profitability description: Per-customer profitability summaries - name: Test Clocks description: >- Test clocks provide programmable time control to simulate subscription and billing scenarios during testing. - name: Events description: Ingest raw metering events that are processed by the meters service. - name: Payments description: >- Create and manage one-off payments. A payment represents a single charge that a merchant wants to collect from a customer. - name: Payment Sessions description: >- Handle payment session lifecycle and processing across various entity types including invoices and subscriptions - name: Costs description: >- A Cost represents the operational or infrastructure expense of serving customers for a given product. Costs are metered (driven by event-based usage) and are tracked in parallel with billable metrics to give merchants visibility into both revenue and cost per customer. - name: ExternalReferences description: >- An `ExternalReference` links a Paygentic entity (e.g. an `Item`) to a record in an external system such as Salesforce or NetSuite. Multiple external records may map to the same Paygentic entity, but each external id is the *primary* reference of at most one entity per merchant. - name: Items description: >- An `Item` is the canonical "thing you sell" that external-system mappings point at. It is fully decoupled from the billing `Product` and holds no pricing/plan/metering, and it is CRM/ERP agnostic — which providers map to it lives entirely in its `ExternalReference` rows. - name: MerchantIntegrations description: >- A `MerchantIntegration` records a merchant's connection to an external provider. One connection per `(merchant, provider)` — re-connecting upserts in place. - name: Approvals description: Submit, decide, cancel, and read maker-checker approvals. - name: Orders description: Manage Orders, their line items, and billing schedules. - name: Billing Schedules description: >- Owner-polymorphic billing schedules with intervals and staged invoice projections. A BillingSchedule belongs to exactly one Order or one Subscription (XOR). Cadence lives on ScheduleIntervals (cadence-on-the-line). paths: /v0/costs: post: tags: - Costs summary: Create description: Create a new metered cost for a product. operationId: createCost requestBody: required: true content: application/json: schema: type: object required: - type - name - unitCost - currency - productId - eventType - aggregation properties: type: type: string enum: - metered description: >- The cost type. Only `metered` costs are supported; they track usage via events. name: type: string description: Human-readable name for the cost. unitCost: type: number minimum: 0 description: >- Cost per unit, multiplied by measured quantity to compute total cost. Must be non-negative. currency: type: string description: ISO 4217 currency code (e.g. USD, EUR). productId: $ref: '#/components/schemas/ProductId' description: The product ID this cost belongs to. unit: type: string description: >- Unit label for metered costs (e.g. 'token', 'request'). Only valid for metered costs. aggregation: type: string enum: - SUM - COUNT - AVG - MIN - MAX - UNIQUE_COUNT - LATEST description: Aggregation method for the metered event. eventType: type: string description: CloudEvents type that identifies the metered event. valueProperty: type: string pattern: ^\$\.[a-zA-Z0-9_]+(\.[a-zA-Z0-9_]+)*$ description: >- JSONPath to extract a numeric value from event data. Must start with `$.` (example: `$.amount` or `$.payload.bytes`). Required for SUM/AVG/MIN/MAX/LATEST aggregations. groupBy: type: object additionalProperties: type: string pattern: ^\$\.[a-zA-Z0-9_]+(\.[a-zA-Z0-9_]+)*$ description: >- Map of dimension name to JSONPath for group-by queries. Each value must start with `$.` (example: `$.region`). Only valid for metered costs. merchantId: $ref: '#/components/schemas/OrganizationId' description: The merchant organization ID that owns this cost. responses: '201': description: Cost created successfully content: application/json: schema: $ref: '#/components/schemas/Cost' '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '500': $ref: '#/components/responses/InternalServerError' components: schemas: ProductId: type: string pattern: ^prod_[a-zA-Z0-9]+$ description: Unique identifier for a product OrganizationId: type: string pattern: ^org_[a-zA-Z0-9]+$ description: Unique identifier for an organization Cost: type: object required: - id - object - type - name - currency - unitCost - productId - merchantId - createdAt - updatedAt properties: id: $ref: '#/components/schemas/CostId' object: type: string enum: - cost default: cost type: type: string enum: - metered name: type: string currency: type: string unitCost: type: string description: Decimal as string to avoid floating point precision loss. unit: type: string nullable: true aggregation: type: string enum: - SUM - COUNT - AVG - MIN - MAX - UNIQUE_COUNT - LATEST nullable: true eventType: type: string nullable: true valueProperty: type: string nullable: true groupBy: type: object additionalProperties: type: string nullable: true productId: $ref: '#/components/schemas/ProductId' merchantId: $ref: '#/components/schemas/OrganizationId' createdAt: type: string format: date-time updatedAt: type: string format: date-time deletedAt: type: string format: date-time nullable: true description: >- Soft-delete timestamp. Always null for active costs returned by the API. CostId: type: string pattern: ^cst_[a-zA-Z0-9]+$ description: Unique identifier for a cost Error: type: object required: - message properties: error: type: string description: >- Coarse HTTP error category (e.g. 'bad_request', 'forbidden'). Maps to the HTTP status code. message: type: string description: >- Human-readable error message. Clients must not parse this field programmatically. code: type: string examples: - TAX_NOT_ENABLED - PAYMENT_SESSION_EXPIRED description: >- Optional semantic business error code for machine-readable discrimination (e.g. 'TAX_NOT_ENABLED'). UPPER_SNAKE_CASE. Clients should check this field, not message. details: type: object description: Additional error details additionalProperties: true example: message: The requested resource was not found error: not_found ValidationError: type: object required: - message - errors properties: error: type: string enum: - validation_error default: validation_error description: Error type indicating validation failure message: type: string description: Human-readable error message errors: type: array items: type: object properties: field: type: string description: The field that failed validation message: type: string description: Validation error message for this field code: type: string description: Validation error code required: - field - message description: Array of field-specific validation errors example: message: Validation failed error: validation_error errors: - field: email message: Invalid email format code: invalid_format responses: BadRequest: description: >- Bad Request - The request could not be understood or was missing required parameters content: application/json: schema: oneOf: - $ref: '#/components/schemas/Error' - $ref: '#/components/schemas/ValidationError' Unauthorized: description: Unauthorized - Authentication failed or user does not have permissions content: application/json: schema: $ref: '#/components/schemas/Error' Forbidden: description: Forbidden - Request is understood but refused content: application/json: schema: $ref: '#/components/schemas/Error' InternalServerError: description: Internal Server Error - Something went wrong on the server side content: application/json: schema: $ref: '#/components/schemas/Error' securitySchemes: BearerAuth: type: http scheme: bearer description: API key authentication ````