> ## 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 Adjustment > Attaches a percentage discount to the subscription for a dated window. Every invoice calculated while the window is open carries one discount line for each discounted charge, and tax is assessed on the reduced amount. An invoice that already exists is not changed, including one still in draft — the discount reaches the periods that close after it is created. There is no update operation, and a window cannot be changed after it is created. To change a rate before any invoice has issued under the discount, delete the adjustment and create a replacement. Once an invoice has issued the adjustment is permanent, so set effectiveTo at creation time whenever the deal has a known end date. ## OpenAPI ````yaml /openapi.json post /v0/subscriptions/{id}/adjustments 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/subscriptions/{id}/adjustments: post: tags: - Subscriptions summary: Create Adjustment description: >- Attaches a percentage discount to the subscription for a dated window. Every invoice calculated while the window is open carries one discount line for each discounted charge, and tax is assessed on the reduced amount. An invoice that already exists is not changed, including one still in draft — the discount reaches the periods that close after it is created. There is no update operation, and a window cannot be changed after it is created. To change a rate before any invoice has issued under the discount, delete the adjustment and create a replacement. Once an invoice has issued the adjustment is permanent, so set effectiveTo at creation time whenever the deal has a known end date. operationId: createSubscriptionAdjustment parameters: - in: path name: id required: true schema: type: string description: The subscription ID requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CreateSubscriptionAdjustmentRequest' example: type: percentageDiscount percentageDiscount: '0.35' effectiveFrom: '2026-01-01T00:00:00Z' effectiveTo: null description: FY26 Growth idempotencyKey: adj_fy26_growth_001 responses: '200': description: >- An adjustment already exists for this idempotency key, and is returned unchanged. Nothing was created. content: application/json: schema: $ref: '#/components/schemas/SubscriptionAdjustment' '201': description: The adjustment was created and applies from its effectiveFrom date. content: application/json: schema: $ref: '#/components/schemas/SubscriptionAdjustment' example: object: subscriptionAdjustment id: subadj_a1b2c3d4e5f6g7h8 subscriptionId: sub_z1a2b3c4d5e6f7g8 type: percentageDiscount percentageDiscount: '0.35' effectiveFrom: '2026-01-01T00:00:00Z' effectiveTo: null description: FY26 Growth createdAt: '2025-12-20T09:30:00Z' '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '404': $ref: '#/components/responses/NotFound' '500': $ref: '#/components/responses/InternalServerError' components: schemas: CreateSubscriptionAdjustmentRequest: type: object additionalProperties: false required: - type - percentageDiscount - effectiveFrom properties: type: type: string enum: - percentageDiscount description: >- The kind of adjustment. `percentageDiscount` reduces every discountable charge by a rate. percentageDiscount: type: string description: >- The discount rate as a decimal fraction between 0 and 1, sent as a string. "0.35" means 35 percent. "1" means 100 percent, not 1 percent. At most 6 decimal places. A value of 0 or above 1 is rejected. effectiveFrom: type: string format: date-time description: The first instant the discount applies. Inclusive. effectiveTo: type: - string - 'null' format: date-time description: >- The instant the discount stops applying. Exclusive, so a window ending on the same date another begins neither overlaps nor leaves a gap. Null means the discount never stops, and it cannot be ended later — set an instant whenever the deal has a known end date. Must be after effectiveFrom. description: type: - string - 'null' maxLength: 255 description: The deal's own name, shown on each discount line of the invoice. idempotencyKey: type: string minLength: 1 maxLength: 255 description: >- A key of your choosing that makes a retry safe. Sending the same key against the same subscription returns the adjustment already created and creates no second one. Without a key a retried request creates a second adjustment, and two percentage discounts compound — two of 0.35 bill 57.75 percent off, not 35 percent. example: adj_fy26_growth_001 SubscriptionAdjustment: type: object required: - object - id - subscriptionId - type - percentageDiscount - effectiveFrom - effectiveTo - description - createdAt properties: object: type: string enum: - subscriptionAdjustment id: type: string description: The adjustment ID subscriptionId: $ref: '#/components/schemas/SubscriptionId' type: type: string enum: - percentageDiscount percentageDiscount: type: string description: >- The discount rate as a decimal fraction between 0 and 1. "0.35" means 35 percent. effectiveFrom: type: string format: date-time description: The first instant the discount applies. Inclusive. effectiveTo: type: - string - 'null' format: date-time description: >- The instant the discount stops applying. Exclusive. Null means the discount never stops. description: type: - string - 'null' description: The deal's own name, shown on each discount line of the invoice. createdAt: type: string format: date-time SubscriptionId: type: string pattern: ^sub_[a-zA-Z0-9]+$ description: Unique identifier for a subscription 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' NotFound: description: Not Found - The requested resource could not be found 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 ````