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+# KLC-API Documentation
+
+## Overview
+
+The `klc-api` is an API designed to facilitate interactions with KalyChain (KLC) via AlchemyPay. It allows users to purchase KLC tokens and ensures that transactions are securely processed and verified.
+
+## Requirements
+
+1. **Integration with AlchemyPay**: The API should be able to handle webhooks from AlchemyPay, verify them, and process the contained information.
+2. **Interaction with EthSigner**: The API should be able to send transactions to EthSigner for signing and then forward the signed transactions to a specified wallet.
+3. **Error Handling**: The API should be robust enough to handle errors, especially when sending tokens. If a transaction fails, the API should retry the transaction at regular intervals until a maximum retry limit is reached.
+4. **Logging**: Every transaction, webhook acknowledgment, and error should be logged for traceability.
+5. **Idempotency**: Ensure that the same webhook is not processed multiple times.
+6. **Security**: The API should use JWT for added security when making JSON-RPC calls to the wallet.
+
+## Features Implemented
+
+### Webhook Handling
+
+- The API listens for incoming POST requests containing transaction details from AlchemyPay.
+- Each webhook is acknowledged immediately to inform AlchemyPay that the webhook has been received.
+- The API checks if the webhook has been processed before to ensure idempotency.
+
+### Transaction Processing
+
+- Transactions are sent to EthSigner for signing.
+- The signed transaction is then forwarded to the specified wallet for execution.
+- If a transaction fails, the API retries the transaction at 60-second intervals until a maximum of 10 retries is reached.
+
+### Error Handling and Logging
+
+- All errors, especially those occurring during token sending, are logged.
+- The API keeps track of the number of retries for each failed transaction.
+
+### Security
+
+- JWT is used to secure JSON-RPC calls to the wallet.
+- Webhooks from AlchemyPay are verified to ensure they are genuine.
+
+### Interaction with EthSigner
+
+- The API creates a transaction payload with necessary details like the sender's address, recipient's address, amount, gas, gas price, and nonce.
+- This payload is sent to EthSigner for signing.
+- The signed transaction is then sent to the wallet for execution.
+
+### Notification to AlchemyPay
+
+- After a successful transaction, the API notifies AlchemyPay about the transaction status.
+- This is done by sending a POST request to AlchemyPay's endpoint with details like order number, transaction status, transaction hash, block height, and a timestamp.
+
+## Tools and Libraries Used
+
+- **Express.js**: For setting up the server and handling HTTP requests.
+- **Axios**: For making HTTP requests to EthSigner, the wallet, and AlchemyPay.
+- **Crypto**: For generating signatures required by AlchemyPay.
+- **Dotenv**: For accessing environment variables.
+
+## Future Enhancements
+
+1. **Admin Dashboard**: A dashboard to monitor and manage transactions, view logs, and handle errors.
+2. **Webhook Verification**: Implement a robust mechanism to verify the authenticity of webhooks from AlchemyPay.
+
+## Links and References
+
+- [AlchemyPay Webhook Documentation](https://alchemypay.readme.io/docs/update-order-status)
+- [EthSigner API Methods](https://docs.ethsigner.consensys.net/Reference/API-Methods#eth_sendtransaction)
+