vlayer Web Proofs (zkTLS)

vlayer provides zero-knowledge TLS (zkTLS) proofs for web requests, enabling you to generate cryptographic proofs of tool calls made through ClawPay. This allows you to verify that specific API calls were made without revealing sensitive data, creating a trustless verification layer for your MCP server interactions on Hedera.

What are Web Proofs?

Web proofs are cryptographic attestations that prove a specific HTTP request was made and received a specific response, without revealing the full contents of the communication. vlayer uses zkTLS technology to generate these proofs, which can be verified independently by anyone.

How It Works

When you enable vlayer for your ClawPay MCP requests:

Your tool call is routed through vlayer notary service via the ClawPay proxy
vlayer generates a cryptographic proof of the request and response
The proof is attached to the MCP response in the metadata
Anyone can verify the proof independently to confirm the request was made

Where vlayer Lives in ClawPay

vlayer is fully integrated into the ClawPay platform, not just an example:

The core vlayer class in apps/mcp generates and validates web proofs
A web proof parser converts proof blobs into structured HTTP data
A proxy hook intercepts tool calls and routes them through vlayer when enabled
A client example demonstrates paid tool calls with web proofs attached

Enabling vlayer in Your Client

Add the x-vlayer-enabled header to your transport to enable web proofs:

import { Client } from "@modelcontextprotocol/sdk/client/index.js";
import { StreamableHTTPClientTransport } from "@modelcontextprotocol/sdk/client/streamableHttp.js";
import { withX402Client } from "@clawpay-hedera/sdk/client";

const client = new Client({
  name: "vlayer-client-example",
  version: "1.0.0",
});


const transport = new StreamableHTTPClientTransport(
  new URL("http://localhost:3000/mcp"),
  {
    requestInit: {
      headers: {
        "x-vlayer-enabled": "true",
      },
    },
  }
);

await client.connect(transport);

const paymentClient = withX402Client(client, {
  wallet: {},
  hederaConfig: {
    privateKey: process.env.HEDERA_PRIVATE_KEY,
    network: "testnet",
    payerAccountId: process.env.HEDERA_ACCOUNT_ID,
    facilitatorFeePayer: "0.0.7162784",
  },
  maxPaymentValue: BigInt(100000),
  confirmationCallback: async () => true,
});

const res = await paymentClient.callTool({
  name: "hbar_account_balance",
  arguments: { accountId: "0.0.6514537" },
});

// Check for web proof in response metadata
if (res._meta?.["vlayer/proof"]) {
  console.log("Web proof attached and verified!");
}

Key Features

Zero-Knowledge: Proofs do not reveal sensitive request or response data
Verifiable: Anyone can independently verify proofs
Transparent: Works seamlessly with existing ClawPay tool calls and Hedera payments
Trustless: No need to trust a third party, proofs are cryptographic
Chain-Agnostic: Proofs verify HTTP responses, independent of the payment layer
HCS Compatible: Combine with Hedera Consensus Service logging for a full tamper-proof audit trail

Use Cases

Audit Trails: Generate verifiable proofs of API calls, combine with HCS logging for a complete tamper-proof record on Hedera
Dispute Resolution: Prove that specific tool calls were made and what data was returned
Transparency: Enable users to verify what requests were made on their behalf
Security: Add an additional layer of cryptographic verification to paid tool calls
On-chain Verification: Proofs are compatible with vlayer Solidity verifiers for smart contract verification

Current Status

vlayer v1.0 has been sunset as they prepare for vlayer Protocol v2.0, a major upgrade with server-side Web Proofs and full compatibility for vouch (client-side) Web Proofs. The ClawPay integration is fully built and ready. Once v2.0 launches and credentials are available, web proofs will generate automatically for any request with the vlayer header enabled.

Without vlayer credentials, the hook gracefully disables itself. Hedera payments still work normally, you just do not get the proof attachment.

Learn More

vlayer Documentation - Learn more about zkTLS and web proofs
Example Repository - Full working example
ClawPay GitHub - Source code and more examples

vlayer Web Proofs (zkTLS)

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