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 MCPay. 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.

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 MCP requests:

Request Execution: Your tool call is executed through vlayer's notary service
Proof Generation: vlayer generates a cryptographic proof of the request/response
Proof Return: The proof is returned alongside the response data
Verification: Anyone can verify the proof independently to confirm the request was made

Enabling vlayer in Your Client

To enable vlayer web proofs for your MCP tool calls, add the x-vlayer-enabled header to your requests:

import { Client } from "@modelcontextprotocol/sdk/client/index.js";
import { StreamableHTTPClientTransport } from "@modelcontextprotocol/sdk/client/streamableHttp.js";
import { withX402Client } from "mcpay/client";
import { createSigner, isEvmSignerWallet, SupportedEVMNetworks } from "x402/types";

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

const transport = new StreamableHTTPClientTransport(new URL(MCP_SERVER_URL), {
  requestInit: {
    headers: {
      'x-mcp-disable-auth': 'true',
      'x-vlayer-enabled': 'true', // Enable vlayer web proofs
    },
  },
});

await client.connect(transport);

Example: Generating a Proof of a Tool Call

The vlayer-client-example demonstrates how to generate a proof for an MCP tool call:

import { Client } from "@modelcontextprotocol/sdk/client/index.js";
import { StreamableHTTPClientTransport } from "@modelcontextprotocol/sdk/client/streamableHttp.js";
import { withX402Client } from "mcpay/client";
import { createSigner, isEvmSignerWallet, SupportedEVMNetworks } from "x402/types";
import { config } from 'dotenv';
config();

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

  const EVM_PRIVATE_KEY = process.env.EVM_PRIVATE_KEY as string;
  const MCP_SERVER_URL = "http://localhost:3005/mcp?target-url=aHR0cHM6Ly9tY3AyLm1jcGF5LnRlY2gvbWNwP2lkPXNydl8ycGZmaHZuaQ%3D%3D"

  const transport = new StreamableHTTPClientTransport(new URL(MCP_SERVER_URL), {
    requestInit: {
      headers: {
        'x-mcp-disable-auth': 'true',
        'x-vlayer-enabled': 'true', // Enable vlayer web proofs
      },
    },
  });

  // ✅ Wait for the connection
  await client.connect(transport);

  const evmSigner = await createSigner("base-sepolia", EVM_PRIVATE_KEY);
  if (!isEvmSignerWallet(evmSigner)) {
    throw new Error("Failed to create EVM signer");
  }

  return withX402Client(client, {
    wallet: {
      evm: evmSigner,
    },
    confirmationCallback: async (payment) => {
      // Payment confirmation logic
      // ...
    }
  });
};

export const getClientResponse = async () => {
  const client = await getClient();
  // ✅ Call tool with vlayer proof enabled
  const res = await client.callTool({
    name: "getUserInfo",
    arguments: {
      userName: "microchipgnu"
    },
  });
  return res;
};

Key Features

Zero-Knowledge: Proofs don't reveal sensitive request/response data
Verifiable: Anyone can independently verify proofs
Transparent: Works seamlessly with existing MCP tool calls
Trustless: No need to trust a third party - proofs are cryptographic

Use Cases

Audit Trails: Generate verifiable proofs of API calls for compliance
Dispute Resolution: Prove that specific tool calls were made
Transparency: Enable users to verify what requests were made on their behalf
Security: Add an additional layer of cryptographic verification

Getting Started

Clone the example:

git clone https://github.com/microchipgnu/mcpay.git
cd examples/vlayer-client-example

Install dependencies:
```
pnpm install
```

Set up environment variables:

cp env.example .env
# Edit .env with your EVM_PRIVATE_KEY

Run the example:
```
pnpm start
```

The example will make a tool call with vlayer enabled, generating a cryptographic proof that can be verified independently.

Learn More

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

vlayer Web Proofs (zkTLS)

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