Proxy
🧩 Latch Payment Proxy
The Latch Payment Proxy is a high-performance coordination layer that verifies on-chain payments, settles x402 transactions, and forwards authorized requests between clients and upstream APIs — enabling pay-per-call access without changing backend logic.
⚙️ How It Works
Client → Latch Payment Proxy → Your APIFlow Overview
Request – The client sends an API or MCP call through the proxy.
402 & Pricing – If the route is monetized, the proxy returns x402 metadata (asset, amount, recipient, expiry).
Payment Verification – The client (or delegated policy) pays on-chain; the proxy validates settlement.
Forward & Respond – Once payment is confirmed, the proxy retries the original request, forwards it to your API, and streams back the response.
This flow allows any API to become pay-protected at the protocol level — stateless and trust-minimized.
🛠 Configuration
You can register and configure payable endpoints through the Latch Console or directly via SDK.
1. Register Your API
Import from OpenAPI spec (recommended) or define manually.
Add authentication headers or query parameters used by your backend.
Specify recipient wallet and supported chain (e.g., Base, Solana, Polygon).
2. Set Pricing
Define per-request pricing (e.g.,
$0.01 USDCor0.05 LATCH).Choose payment timing:
Async – Verify payment asynchronously (fastest).
Before – Settle payment before execution.
After – Verify after execution (safest).
3. Settlement Mode
Select the strictness of on-chain verification:
Simulated – Marked valid after simulation (for testing).
Submitted – Valid once broadcast to the network.
Confirmed – Waits for full on-chain confirmation (highest assurance).
🧱 API Metadata
When using an OpenAPI spec, metadata (methods, inputs, and response schemas) are auto-imported. This ensures that MCP clients and AI agents can understand and interact with your API autonomously.
Manual configuration is also supported by defining method, path, parameters, and schemas directly.
🧪 Testing
Within the Latch Console, you can test your payable endpoints:
Connect your wallet to simulate a payment.
The proxy executes the full x402 payment-verification flow.
You receive your API response plus a full payment log trace.
🔒 Design Goals
Reliability
Stateless architecture with built-in retry and failover via Latch Facilitator
Security
On-chain payment validation before forwarding
Flexibility
Works with REST, MCP, and OpenAPI
Interoperability
Native compatibility with MCP clients and x402 agents
Scalability
Optimized for edge and serverless environments
🌐 Endpoint
Mainnet: https://x402.latchmcp.app
Explorer: x402scan link
Last updated