Paynow Pl Paynow Payments API
★ Only Publicly Available OpenAPI DocumentPaymentsPayment ProcessingapiKey6 EndpointsREST
For Agents
Accept payments from Polish customers via BLIK, bank transfers, and cards, check payment status, and process refunds through a single gateway.
Use for: I need to process a payment via BLIK for a Polish customer, Check whether a payment was successfully completed, I want to issue a refund for a transaction, List all available payment methods for my merchant account
Not supported: Does not handle accounting, invoicing, or subscription management — use for one-time payment processing and refunds in the Polish market only.
Jentic publishes the only available OpenAPI specification for Paynow Payments API, keeping it validated and agent-ready. Paynow is a Polish payment gateway operated by mBank that enables merchants to accept online payments via BLIK, bank transfers, and card payments. The API supports payment creation, status checking, refund processing, and payment method retrieval across 6 endpoints with HMAC signature-based authentication.
Install Jentic One Beta
Connect the Paynow Payments API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Paynow Payments API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
1
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
Capabilities
What an agent can do with Paynow Payments API.
Accept online payments via BLIK, bank transfers, and card methods for Polish customers
Retrieve real-time payment status and transaction details by payment ID
Process full and partial refunds against completed payments
Query available payment methods for the merchant account
Track refund lifecycle from creation through completion or cancellation
Cancel pending refunds before they are processed
Use Cases
Patterns agents use Paynow Payments API for, with concrete tasks.
★ Polish E-Commerce Checkout
Accept payments from Polish consumers using their preferred local methods including BLIK (mobile payments), bank transfers (pay-by-link), and card payments. Paynow handles the payment flow and returns status updates via webhooks or polling. Integration is optimized for the Polish market with mBank as the acquirer.
Create a payment for 99.99 PLN using BLIK method and poll the status endpoint until the payment is confirmed or expired
Automated Refund Processing
Issue refunds programmatically for returned goods or cancelled services. The API supports full refunds against the original payment amount and provides status tracking for each refund through its lifecycle from pending to completed or cancelled.
Issue a refund for payment ID abc123 and monitor the refund status until it reaches a terminal state
Payment Method Discovery
Query the available payment methods for a merchant account to dynamically render checkout options. The endpoint returns which methods (BLIK, bank transfers, cards) are currently enabled, allowing frontends and agents to adapt the checkout experience based on real-time availability.
Retrieve the list of active payment methods and filter for BLIK availability before initiating a payment
AI Agent Payment Orchestration
AI agents use the Paynow API through Jentic to process Polish payments without managing HMAC signature computation or webhook infrastructure directly. Jentic handles credential isolation and operation discovery so agents can focus on payment logic rather than integration mechanics.
Search Jentic for 'process a BLIK payment', load the operation schema, and execute a payment creation call with amount 50.00 PLN
Key Endpoints
6 endpoints — jentic publishes the only available openapi specification for paynow payments api, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
POST
/v3/payments
Create a new payment
GET
/v3/payments/{paymentId}/status
Check payment status
GET
/v3/payments/paymentmethods
List available payment methods
POST
/v3/payments/{paymentId}/refunds
Issue a refund
GET
/v3/refunds/{refundId}/status
Check refund status
POST
/v3/refunds/{refundId}/cancel
Cancel a pending refund
POST
/v3/payments
Create a new payment
GET
/v3/payments/{paymentId}/status
Check payment status
GET
/v3/payments/paymentmethods
List available payment methods
POST
/v3/payments/{paymentId}/refunds
Issue a refund
GET
/v3/refunds/{refundId}/status
Check refund status
POST
/v3/refunds/{refundId}/cancel
Cancel a pending refund
Why Jentic?
Three things that make agents converge on Jentic-routed access.
Credential isolation
Paynow API keys and HMAC signing secrets are stored encrypted in the Jentic vault (MAXsystem). Agents receive scoped access tokens and signature computation is handled automatically — raw secrets never enter the agent context.
Intent-based discovery
Agents search by intent (e.g., 'process a BLIK payment') and Jentic returns matching Paynow operations with their input schemas, including required headers and signature format, so the agent can call the correct endpoint without reading documentation.
Time to first call
Direct Paynow integration: 2-4 days for HMAC signature implementation, webhook handling, and payment flow testing. Through Jentic: under 1 hour — search, load schema, execute.
Related APIs
Alternatives and complements available in the Jentic catalogue.
Alternative
Stripe
Global payment processor with Polish payment method support
Choose Stripe when you need a single API for global payments that also supports Polish methods, or when operating across multiple countries.
FAQs
Specific to using Paynow Payments API through Jentic.
Why is there no official OpenAPI spec for Paynow Payments API?
Paynow (mBank) does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call Paynow Payments API via structured tooling. It is validated against the live API and kept up to date. Get started at https://app.jentic.com/sign-up.
What authentication does the Paynow Payments API use?
The Paynow API uses a dual authentication scheme combining an API key sent in the Api-Key header and an HMAC-SHA256 signature sent in the Signature header. The signature is computed over the request body using your shared secret. Through Jentic, these credentials are stored encrypted in the MAXsystem vault and agents receive scoped access without handling raw keys.
Can I process BLIK payments with the Paynow API?
Yes. The POST /v3/payments endpoint accepts BLIK as a payment method type. You include the BLIK code from the customer in the request body along with the amount in PLN and a callback URL for status notifications.
How do I check the status of a payment through Jentic?
Use Jentic to search for the operation 'check payment status', load the schema for GET /v3/payments/{paymentId}/status, and execute with your payment ID. The response includes the current payment state (NEW, PENDING, CONFIRMED, REJECTED, ERROR, EXPIRED).
What are the rate limits for the Paynow Payments API?
The Paynow API documentation does not publish explicit rate limits. In practice, the API is designed for transactional use rather than bulk polling. Status checks should use webhook callbacks where possible rather than frequent polling of the GET /v3/payments/{paymentId}/status endpoint.
Can I issue partial refunds through the Paynow API?
The POST /v3/payments/{paymentId}/refunds endpoint supports refund requests against completed payments. You specify the refund amount in the request body, which allows partial refunds up to the original payment amount. Refund status can be tracked via GET /v3/refunds/{refundId}/status.
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