> ## Documentation Index > Fetch the complete documentation index at: https://docs.beinfi.com/llms.txt > Use this file to discover all available pages before exploring further. # Create a link with a product > From nothing to a payable URL in one call. The product is identified by its `key`: a new key creates it, a known one reuses it, and pricing that differs from the current one publishes a new version. Links already shared keep selling the price they advertised. Every call creates a new link, so you can have one URL per campaign. The response carries the `url` to send the payer; you do not need to pass your account slug. ## OpenAPI ````yaml /api-reference/openapi.en.json post /payment-links openapi: 3.1.0 info: title: Infi API version: 0.0.1 description: > The Infi REST API: catalog, customers, usage metering, subscriptions, invoices, payments and checkout. **Authentication.** Send your secret key as `Authorization: Bearer sk_test_…` (sandbox) or `sk_live_…` (production). The key prefix selects the environment. Checkout routes (`/pay/*`) and `/public/*` take no key: they run in the payer's browser. **Idempotency.** Every request that changes data requires an `Idempotency-Key` header. A retry with the same key returns the original response instead of running again. **Amounts.** Money and quantities travel as decimal strings (`"150.00"`, `"0.0001"`), never as floating-point numbers. **Errors.** The body carries `error_code` (stable, branch on it), `message` (for humans) and `tracer_id` (send it to support). Rate-limit and idempotency errors are nested under `error`, with `code` and `request_id`. servers: - url: https://api-sandbox.beinfi.com description: Sandbox - url: https://api.beinfi.com description: Production security: - bearerAuth: [] tags: - name: Catalog - name: Customers - name: Metering - name: Subscriptions - name: Invoices - name: Payments - name: Checkout - name: Coupons - name: Billing - name: Account - name: Webhooks - name: Test account - name: Rail - name: Storefronts paths: /payment-links: post: tags: - Catalog summary: Create a link with a product description: > From nothing to a payable URL in one call. The product is identified by its `key`: a new key creates it, a known one reuses it, and pricing that differs from the current one publishes a new version. Links already shared keep selling the price they advertised. Every call creates a new link, so you can have one URL per campaign. The response carries the `url` to send the payer; you do not need to pass your account slug. operationId: createPaymentLinkWithProduct requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CreatePaymentLinkWithProductRequest' responses: '201': content: application/json: schema: $ref: '#/components/schemas/PaymentLink' description: Link created. '401': $ref: '#/components/responses/Unauthorized' '422': content: application/json: schema: $ref: '#/components/schemas/ValidationError' description: >- Invalid product definition: a missing `key`, a `billingCycle` that contradicts the `pricingModel`, or a price the model requires is missing. security: - BearerAuth: [] components: schemas: CreatePaymentLinkWithProductRequest: type: object required: - product properties: product: $ref: '#/components/schemas/InlineProductSpec' description: The product, defined inline and identified by its `key`. successUrl: type: - string - 'null' maxLength: 2048 description: >- Where the payer goes after paying, with `?status=success&invoice=…` appended. Absolute `http(s)` URL. cancelUrl: type: - string - 'null' maxLength: 2048 description: >- Offered to the payer as "back to the store" while the checkout is open. Absolute `http(s)` URL. PaymentLink: type: object properties: id: type: string format: uuid productId: type: string format: uuid token: type: string description: The link's public token, part of the `url`. url: type: string description: >- The address to send the payer. Use this value instead of building the URL yourself. productVersionId: type: - string - 'null' format: uuid description: >- The product version this link sells, fixed at creation. Publishing a new version does not reprice a link already issued. When `null`, the link sells the latest published version at payment time. active: type: boolean description: '`false` once revoked.' revokedAt: type: - string - 'null' format: date-time description: When the link was revoked. createdAt: type: string format: date-time successUrl: type: - string - 'null' description: >- Where the payer goes after paying, with `?status=success&invoice=…` appended. cancelUrl: type: - string - 'null' description: >- Offered to the payer as "back to the store" while the checkout is open; also the `?status=error` destination when the charge expires in the embedded checkout. description: >- A reusable, revocable payment link bound to a product. Anyone holding it can open the checkout; it is meant to be copied and shared. ValidationError: type: object required: - message - error_code - tracer_id - errors properties: message: type: string error_code: $ref: '#/components/schemas/ErrorCode' tracer_id: type: string errors: type: array items: type: object required: - field - value - constraint - description properties: field: type: string value: type: string constraint: type: string description: type: string description: >- Per-field detail (`field`, `description`). Always present on a `422`; may be empty. description: >- Body of a `422`. Same shape as `Error`, plus `errors[]` with per-field detail. That is where the sentence telling you what to fix lives (for example, "product has no published version"). InlineProductSpec: type: object required: - key - pricingModel properties: key: type: string description: >- Stable product key, unique in your account. Required: it is what makes two calls for the same product resolve to one product. name: type: string description: Display name. Defaults to `key`. type: type: string enum: - agent - item description: '`item` (default) or `agent`.' description: type: - string - 'null' pricingModel: type: string enum: - subscription - one_time - usage - prepaid description: '`subscription`, `one_time`, `usage` or `prepaid`.' currency: type: string minLength: 3 maxLength: 3 description: '3-letter ISO 4217 code. Default: `BRL`.' billingCycle: type: - string - 'null' enum: - weekly - monthly - annual - null description: Required for `subscription` and `prepaid`; omit it for other models. basePrice: type: - string - 'null' description: Base price as a decimal string (`"49.90"`). meters: type: array items: $ref: '#/components/schemas/InlineMeterSpec' description: >- The product's meters, created once by `name`. A meter that already exists is not changed by this call. prices: type: array items: $ref: '#/components/schemas/InlinePriceSpec' description: >- The version's complete price list. A list that differs from the current version publishes a new version. Omit the field to leave prices alone; an empty array means "no prices". description: >- A product defined on link creation, identified by its `key`. A new key creates the product; a known key reuses it, and pricing that differs from the current version publishes a new version. Links already in circulation keep selling what they advertised. Error: type: object required: - message - error_code - tracer_id properties: message: type: string description: Human-readable sentence. error_code: $ref: '#/components/schemas/ErrorCode' description: Stable error code. Branch on it. tracer_id: type: string description: Request id. Include it when contacting support. description: >- The standard error body. It is flat (no `error` wrapper) and the trace id is `tracer_id`. ErrorCode: type: string examples: - internal_error - validation_failed - bad_request - unauthorized - forbidden - not_found - conflict - rate_limited description: >- Stable error code. The list is open: besides the generic codes, each area defines its own (`coupon_expired`, `insufficient_balance`, `version_not_draft`, `idempotency_key_reused`…). Handle a code you do not recognize by its HTTP status and show `message`; do not fail parsing the response. InlineMeterSpec: type: object required: - name properties: name: type: string description: The key you send in `track()`. Cannot change after creation. displayName: type: string unit: type: string enum: - token - request - unit description: '`token`, `request` or `unit`.' aggregation: type: string enum: - sum - count - unique_count - max - last description: '`sum`, `count`, `unique_count`, `max` or `last`.' valueProperty: type: - string - 'null' description: Event field carrying the numeric value. Unused with `count`. InlinePriceSpec: type: object required: - meter - model properties: meter: type: string description: >- The `name` of the meter this price rates. Required: an amount with no meter is the product's `basePrice`. model: type: string enum: - flat - per_unit - tiered - volume - package description: '`flat`, `per_unit`, `tiered`, `volume` or `package`.' unitAmount: type: - string - 'null' description: Amount per unit as a decimal string. tiers: type: object description: Price tiers for `tiered`, `volume` and `package`. currency: type: string minLength: 3 maxLength: 3 description: Optional; defaults to the product's currency. responses: Unauthorized: content: application/json: schema: $ref: '#/components/schemas/Error' description: Missing or invalid API key. securitySchemes: bearerAuth: type: http scheme: bearer description: >- Your account's secret key: `Authorization: Bearer sk_test_…` or `sk_live_…`. Server-side only. ````