Payware

payware MCP Server

Official MCP (Model Context Protocol) server for payware payment API integration. This server enables AI assistants to interact with payware APIs, automating integration workflows for all partner types.

Releases are published to npm as @payware/mcp-server and to the official MCP Registry as io.github.payware/mcp-server. MIT licensed, see LICENSE.

Who Is This For?

• Merchants - Accept payments, manage products, generate transaction reports
• ISVs (Independent Software Vendors) - Build multi-merchant platforms with OAuth2 token management
• Payment Institutions - Process A2A transfers, handle Payment Choice Architecture with multiple payment methods

What's New in v1.2.0

• SHA-256 Authentication - Upgraded from MD5 to SHA-256 for JWT content hashing (contentSha256 header)
• Updated Error Codes - New error codes: ERR_INVALID_CONTENT_HASH, ERR_MISSING_CONTENT_HASH
• Backward Compatibility - Deprecated MD5 functions retained for legacy support

Features

🔐 Authentication Tools

• RSA Key Generation: Generate secure 2048-bit RSA key pairs
• JWT Token Creation: Create properly formatted JWT tokens
• Sandbox Setup: Configure sandbox authentication

💳 Transaction Tools

• Create Transaction: Support PLAIN, QR, and BARCODE transactions
• Process Transaction: Process transactions with Payment Choice Architecture support
• Transaction Status: Check transaction status by ID
• Transaction History: Get finalized transaction details
• Callback Simulation: Test callback scenarios for merchants and payment institutions

📍 Point of Interaction (POI) Tools

• Set Price: Configure POI with amount, currency, and payment details
• Cancel Price: Clear active price from POI
• Get POI: Retrieve POI details and current state
• Get Status: Check POI transaction status
• Get QR Code: Generate QR code for POI payments
• List POIs: List all POIs for a merchant

📣 Campaign, Placement and Airing Tools

For merchants, and for ISVs acting for them. Changes need the merchant's PRM plan; reading works on every plan.

• Placements: Distribute a product through posters, TV spots, packaging, links or tags, each with its own pl ID, so every payment it starts is attributed to it. Includes the QR code, barcode and short link of each placement
• Campaigns: Group placements, across products, and read their combined results
• Airing Rules: Schedule when a placement is on air, with recurrences, time windows and time zones, and replace a whole schedule in one call
• Airing Calendar: Every airing across all products in a time range
• Results: Offers shown, payments started and confirmed, and confirmed amounts per placement or campaign

📋 Logs Tools (Premium)

• Query Logs: Search and filter application logs by level, logger, message content, and date range
• Log Status: Check log availability and storage information
• Download Logs: Get compressed archive of logs for offline analysis

🛠️ Utility Tools

• Advanced Code Generation: Generate complete integration code across 8 languages (Python, Node.js, PHP, Java, C#, Go, Ruby, cURL) with 16+ framework support
• Framework Integration: Framework-specific examples for Django, FastAPI, Express, NestJS, Laravel, Spring Boot, ASP.NET, and more
• Real-world Scenarios: Generate complete integration scenarios (e-commerce, ISV multi-merchant, P2P payments)
• Comprehensive Documentation: Auto-generate complete API documentation with code examples
• Request Formatting: Format and validate API requests

Quick Start

1. Installation

From npm (recommended):

npm install -g @payware/mcp-server

From source:

git clone https://github.com/payware/mcp-server.git
cd mcp-server
npm install

2. Environment Configuration

Copy the example environment file and configure your credentials:

cp .env.example .env

Edit .env file:

# Partner ID from payware dashboard
PAYWARE_PARTNER_ID=your_partner_id_here

# Path to private key file (relative to project root)
PAYWARE_SANDBOX_PRIVATE_KEY_PATH=keys/sandbox-your-private-key.pem
PAYWARE_PRODUCTION_PRIVATE_KEY_PATH=keys/production-your-private-key.pem

# Optional: Sandbox base URL (defaults to https://sandbox.payware.eu/api)
PAYWARE_SANDBOX_URL=https://sandbox.payware.eu/api

⚠️ Security Note: Never commit the .env file to version control. It contains sensitive credentials.

Choosing toolsets

Every tool definition goes into the assistant's context on every turn, and a merchant has over 70 of them. To offer only the groups you use, set PAYWARE_MCP_TOOLSETS to a comma-separated list:

PAYWARE_MCP_TOOLSETS=products,placements

Toolsets: auth, transactions, products, placements, data, logs, poi, shops, onboarding, utils. Unset, or all, loads every tool. An unknown name is ignored with a warning in the server log. A tool outside the chosen toolsets is neither listed nor callable; this narrows what the assistant is offered and does not change what your partner account may do. An ISV that obtains OAuth2 tokens through this server includes auth.

3. Start the MCP Server

npm start

4. Basic Integration Flow

1. Generate RSA Keys

   Tool: payware_authentication_generate_rsa_keys
   

2. Create JWT Token

   Tool: payware_authentication_create_jwt_token
   Parameters:
   - partnerId: (from PAYWARE_PARTNER_ID)
   - privateKey: (from environment-specific key path)
   

3. Setup Sandbox

   Tool: payware_authentication_setup_sandbox_auth
   Parameters:
   - partnerId: (from PAYWARE_PARTNER_ID)
   

4. Create Transaction

   Tool: payware_operations_create_transaction
   Parameters:
   - partnerId: (from PAYWARE_PARTNER_ID)
   - privateKey: (from environment-specific key path)
   - amount: 10.00
   - currency: EUR
   - reasonL1: "Payment description"
   - type: PLAIN
   

5. Check Status

   Tool: payware_operations_get_transaction_status
   Parameters:
   - partnerId: (from PAYWARE_PARTNER_ID)
   - privateKey: (from environment-specific key path)
   - transactionId: TRANSACTION_ID
   

API Request Structure

The payware MCP server transforms flat parameter inputs into the proper nested JSON structure required by the payware API:

Create Transaction Request Structure

{
  // ROOT LEVEL - Transaction metadata
  "shop": "SHOP001",                    // Optional: Shop code
  "account": "GB29NWBK60161331926810",  // Optional: Account identifier
  "friendlyName": "Your Shop Name",     // Optional: Account holder name
  "callbackUrl": "https://callback.url", // Optional: HTTPS callback URL
  "passbackParams": "{\"orderId\":\"12345\"}", // Optional: Callback parameters
  
  // TRANSACTION DATA - Required transaction information
  "trData": {
    "amount": "25.50",              // String/Number: Amount (can be "0.00" for flexible amounts)
    "currency": "EUR",              // REQUIRED: ISO 3-character currency code
    "reasonL1": "Payment for services", // REQUIRED: Transaction description (max 100 chars)
    "reasonL2": "Order #12345"      // Optional: Additional description (max 100 chars)
  },
  
  // TRANSACTION OPTIONS - Transaction behavior settings
  "trOptions": {
    "type": "QR",                   // PLAIN, QR, or BARCODE (default: PLAIN)
    "timeToLive": 300               // Seconds: 60-600 (default: 120)
  },
  
  // QR OPTIONS - Only included when type=QR
  "qrOptions": {
    "qrFormat": "PNG",              // PNG, SVG, JPG, GIF, BMP (default: SVG)
    "qrBorder": 4,                  // Border modules: 1-10 (default: 4)
    "qrErrorCorrection": "QUARTILE", // LOW, MEDIUM, QUARTILE, HIGH (default: QUARTILE)
    "qrScale": 16,                  // Pixel size: 1-100 (default: 16, irrelevant for SVG)
    "qrVersion": 10                 // QR version: 1-40 (default: 10, auto if not specified)
  },
  
  // BARCODE OPTIONS - Only included when type=BARCODE
  "barOptions": {
    "barFormat": "SVG",             // PNG, SVG, JPG (default: SVG)
    "barModuleWidth": 2,            // Module width: 1-10 (default: 2)
    "barBarHeight": 100,            // Height: 15-1000 (default: 100)
    "barFontSize": 12,              // Font size: 0-24 (default: 12)
    "barHumanReadableLocation": "NONE" // NONE, BOTTOM, TOP (default: NONE)
  }
}

Parameter Mapping

When using MCP tools, parameters are automatically mapped to the correct API structure:

Available Tools

Code Generation & Documentation

payware_generate_code_example

Advanced multi-language code generation with framework support

Supports 60+ operations across all partner types:

• Transactions: create_transaction, get_transaction_status, cancel_transaction, process_transaction, get_transaction_history, simulate_callback
• Products: create_product, get_product, update_product, delete_product, list_products, get_product_image, create_schedule, update_schedule, delete_schedule, list_schedules
• OAuth2 (ISV only): obtain_token, get_token_info, create_token_simple, refresh_token, revoke_token, list_active_tokens
• Data: generate_report, get_report_status, export_report, download_export, cancel_report, list_reports, get_analytics_summary, create_custom_report
• P2P (Payment Institution): initiate_p2p_transfer, accept_p2p_transfer, reject_p2p_transfer, get_p2p_transfer_status, list_p2p_transfers, cancel_p2p_transfer, create_p2p_link, get_p2p_analytics
• Soundbites (Payment Institution): register_audio, get_audio, update_audio, delete_audio, list_audios, create_soundbite_transaction, stream_audio, download_audio, get_soundbite_analytics, create_audio_playlist, get_audio_preview

payware_generate_documentation

Comprehensive documentation generator

Generates complete API documentation with working code examples for any partner type and programming language combination.

Authentication

payware_authentication_generate_rsa_keys

Generate RSA key pair for API authentication.

Parameters:

• keySize (optional): RSA key size in bits (default: 2048)

payware_authentication_create_jwt_token

Create JWT token for API authentication.

Parameters:

• partnerId (required): Partner ID from payware
• privateKey (required): RSA private key in PEM format

payware_authentication_validate_jwt

Validate JWT token format and signature.

Parameters:

• token (required): JWT token to validate
• partnerId (required): Partner ID for validation

payware_authentication_test_jwt

Test JWT token with payware API.

Parameters:

• token (required): JWT token to test
• partnerId (required): Partner ID

payware_authentication_setup_sandbox_auth

Setup sandbox authentication configuration.

Parameters:

• partnerId (required): Partner ID from payware
• privateKey (optional): Private key for validation

Transactions

Transaction Status Overview

payware transactions can have the following statuses:

ACTIVE Status:

• ⏳ ACTIVE: Active transaction pending processing or finalizing
• This is the only status returned by payware_transactions_get_transaction_status
• Use GET /transactions/{id} endpoint

Final Statuses:

• ✅ CONFIRMED: Successfully finalized
• ❌ DECLINED: Declined by the user, processing or finalizing payment institutions
• 💥 FAILED: Failed due to technical reasons or other
• ⏰ EXPIRED: Time to live of the transaction has passed
• 🚫 CANCELLED: Transaction canceled by the originator

These final statuses are only available through payware_operations_get_transaction_history using GET /transactions-history/{id} endpoint.

payware_operations_create_transaction

Create a new transaction with full API structure support.

Key Parameters:

• currency (required): ISO 3-character code (EUR, USD, GBP, etc.)
• reasonL1 (required): Transaction description (max 100 chars)
• partnerId (required): Partner ID from payware dashboard
• privateKey (required): RSA private key for JWT signing
• amount (optional): Currency value (default: "0.00" for flexible amounts)
• type (optional): PLAIN, QR, or BARCODE (default: PLAIN)
• timeToLive (optional): Payment timeout in seconds, 60-600 (default: 120)

QR Options (when type=QR):

• qrFormat: PNG, SVG, JPG, GIF, BMP (default: SVG)
• qrErrorCorrection: LOW, MEDIUM, QUARTILE, HIGH (default: QUARTILE)
• qrScale, qrBorder, qrVersion: Size and appearance settings

Barcode Options (when type=BARCODE):

• barFormat: PNG, SVG, JPG (default: SVG)
• barModuleWidth, barBarHeight, barFontSize: Size settings

payware_operations_get_transaction_status

Get status of ACTIVE transactions only. For completed/finalized transactions use history tool.

Parameters:

• transactionId (required): Transaction ID (starts with 'pw')
• partnerId (required): Partner ID
• privateKey (required): Private key for JWT signing

payware_operations_simulate_callback

Simulate callback scenarios for testing.

Parameters:

• transactionId (required): Transaction ID
• status (optional): CONFIRMED, DECLINED, FAILED, EXPIRED, or CANCELLED (default: CONFIRMED)
• callbackUrl (optional): URL where callback would be sent
• amount (optional): Transaction amount (default: 10.00)
• currency (optional): Currency (default: EUR)
• type (optional): Transaction type (default: PLAIN)

Utilities

payware_generate_code_example

Generate production-ready code examples for any payware operation.

Parameters:

• operation (required): Operation to generate - see complete list below
• language (optional): python, nodejs, php, java, csharp, curl (default: python)
• partner_type (optional): merchant, isv, payment_institution (default: merchant)
• include_comments (optional): Include detailed code comments (default: true)
• include_error_handling (optional): Include comprehensive error handling (default: true)

Available Operations by Category:

Authentication:

• authentication - JWT authentication setup

Transaction Operations (all partner types):

• create_transaction - Create a new payment transaction
• get_transaction_status - Get transaction status and details
• process_transaction - Process a pending transaction
• cancel_transaction - Cancel a pending transaction

Product Operations (merchant, isv):

• create_product - Create a new product
• get_product - Get product details
• list_products - List all products

POI Operations (isv):

• set_price - Set price on a Point of Interaction device
• cancel_price - Cancel active price on POI
• get_poi - Get POI details
• get_poi_status - Get POI transaction status
• get_poi_qrcode - Generate QR code for POI
• list_pois - List all POIs for a merchant

OAuth2 Operations (isv only):

• obtain_token - Obtain OAuth2 access token
• get_token_info - Get OAuth2 token information

Data Operations (all partner types):

• generate_report - Generate analytics report
• get_report_status - Get report generation status

P2P Operations (payment_institution only):

• initiate_p2p_transfer - Initiate peer-to-peer transfer
• accept_p2p_transfer - Accept P2P transfer

Soundbites (payment_institution only):

• register_audio - Register audio content for soundbite transactions

payware_generate_documentation

Generate comprehensive API documentation with code examples.

Parameters:

• language (optional): Target programming language (default: python)
• partnerType (optional): merchant, isv, payment_institution (default: merchant)
• includeScenarios (optional): Include real-world integration scenarios (default: true)
• outputFormat (optional): markdown, html, json (default: markdown)

payware_utils_format_request

Format and validate API requests with deterministic JSON serialization for SHA-256 consistency.

Parameters:

• type (required): transaction, headers, or curl
• data (optional): Data to format
• jwtToken (optional): JWT token for headers
• signature (optional): Request signature
• endpoint (optional): API endpoint for curl
• method (optional): HTTP method (default: POST)

payware_utils_format_json_deterministic

Format JSON with deterministic property ordering for consistent SHA-256 calculation.

Parameters:

• data (required): Object to serialize
• minimize (optional): Remove whitespace (default: true)

payware_utils_server_info

Get MCP server information and configuration.

Note: All transaction data is serialized using consistent property ordering to prevent content hash mismatch errors.

Dependencies

• @modelcontextprotocol/sdk: MCP server framework
• axios: HTTP client for API calls
• jsonwebtoken: JWT token creation
• node-forge: RSA key generation

Environment

• Sandbox Only: All API calls are restricted to sandbox environment
• Base URL: https://sandbox.payware.eu/api/v1
• Supported Currencies: EUR, USD, GBP
• Supported Transaction Types: PLAIN, QR, BARCODE

Security

⚠️ Important Security Notes:

Environment Variables

• REQUIRED: Use environment variables for all credentials
• Never commit .env files to version control
• Use different credentials for development and production
• Store private key files outside web-accessible directories

Private Key Security

• Generate separate key pairs for sandbox and production
• Store private keys with restricted file permissions (600)
• Never embed private keys in source code
• Rotate keys regularly according to security policies

API Security

• This server is designed for sandbox testing only
• Never use sandbox keys in production environment
• Implement proper error handling in production
• Use HTTPS for all API communications
• Validate all input parameters
• Implement rate limiting and monitoring

JSON Serialization & SHA-256 Consistency

⚠️ CRITICAL: payware API requires deterministic JSON serialization for SHA-256 calculation

• Property Order: JSON objects must have consistent property ordering
• Minimized Format: No whitespace or formatting in request bodies
• SHA-256 Calculation: Must be calculated from the exact same JSON string sent to API
• Implementation: This server uses deterministic JSON serialization to ensure consistency

Example of correct JSON format:

{"trData":{"amount":"25.50","currency":"EUR","reasonL1":"Payment description"},"trOptions":{"timeToLive":300,"type":"PLAIN"}}

Why this matters:

• Different property orders produce different SHA-256 hashes
• Hash mismatch results in ERR_INVALID_CONTENT_HASH errors
• Server validates that JWT contentSha256 matches request body SHA-256

Troubleshooting

Common Issues

1. Authentication Failed (ERR_INVALID_SIGNATURE)

   • Root Cause: Public key registered with payware doesn't match your private key
   • Solution: Ensure the public key registered on payware site corresponds to your private key
   • Verification: Use openssl rsa -in privateKey.pem -pubout to extract public key from private key
   • Status: ✅ Resolved - Keys must be properly registered on payware partner portal

2. Content Hash Mismatch Error (ERR_INVALID_CONTENT_HASH)

   • Root Cause: Inconsistent JSON property ordering
   • Solution: Use deterministic JSON serialization (implemented in this server)
   • Symptoms: Server logs show different expected vs actual SHA-256 hashes
   • Prevention: Always use createMinimizedJSON() from /src/core/utils/json-serializer.js
   • Status: ✅ Fixed - Deterministic JSON serialization implemented

3. Transaction Creation Failed

   • Ensure all required parameters are provided
   • Check amount is non-negative
   • Verify transaction type is supported
   • Status: ✅ Working - Create and cancel operations confirmed functional

4. MCP Connection Issues

   • Ensure server is started with npm start
   • Check that MCP client is properly configured
   • Verify no firewall blocking stdio communication
   • Note: Use MCP Inspector (npm run inspector) for debugging

Proxy and Bridge Tools

HTTP Proxy Server (npm run proxy):

• Bridges MCP tools to HTTP REST API
• Useful for testing tools via HTTP requests
• Documentation: README-proxy.md

MCP Bridge (npm run bridge):

• Connects MCP server to MCP Inspector
• Essential for debugging and development
• Use with: npm run inspector

Testing Status

✅ Confirmed Working Operations:

• JWT token creation with RS256 algorithm
• Transaction creation (POST /api/transactions)
• Transaction cancellation (PATCH /api/transactions/{id})
• Deterministic JSON serialization for SHA-256 consistency
• Public/private key pair validation

🧪 Test Results:

• All MCP tools tested successfully with real payware sandbox API
• Both create and cancel transaction flows working end-to-end
• Signature validation resolved with proper key registration

Support

For issues related to:

• MCP Server: Check server logs and MCP client configuration
• payware API: Refer to payware documentation and sandbox status
• Integration: Use code examples and formatting tools provided
• Key Issues: Ensure public key is registered on payware partner portal

License

MIT License