MCP x402 - Evidence-Backed Web Verification MCP server

MCP x402 — Evidence-Backed Web Verification for AI Agents

Verify a seller, product, offer, policy, or claim before an agent acts

Give an AI agent a public HTTP(S) page and 1 to 10 concrete conditions. The verificar_condicoes tool returns an evidence-based decision for every condition:

• confirmado — the page clearly supports the condition.
• rejeitado — the page clearly contradicts the condition.
• incerto — the available page evidence is insufficient.

Each verification includes the final source URL, page title, timestamp, condition-by-condition explanation, quoted evidence when available, a unique verificationId, and a SHA-256 pageHash.

Designed for

• AI purchasing and procurement agents;
• seller, product and offer verification;
• pre-purchase due diligence;
• policy and terms checking;
• commercial automation that requires evidence before taking action.

Simple x402 integration

• Free preflight validation before payment.
• $0.05 USDC per verification on Base mainnet.
• No account or subscription required.
• Available through MCP and HTTP.
• Ready-to-run buyer included in this repository.
• Bazaar discovery metadata enabled on the paid HTTP and MCP surfaces.

Live endpoints

• MCP: https://mcp-x402-production.up.railway.app/mcp
• Free MCP preflight: POST https://mcp-x402-production.up.railway.app/preflight/mcp
• Free verification preflight: POST https://mcp-x402-production.up.railway.app/preflight/verify-conditions
• Paid verification: POST https://mcp-x402-production.up.railway.app/verify-conditions
• Health: GET https://mcp-x402-production.up.railway.app/health

The service also provides paid public URL analysis and general AI consultation through analisarurl and consultaria.

Live Service

• Base URL: https://mcp-x402-production.up.railway.app
• Health check: GET /health
• MCP endpoint: POST /mcp
• Paid URL analysis: POST /analyze
• Price: $0.05 USDC per paid request
• Network: Base mainnet (eip155:8453)

Production Status

• Production deployment active on Railway
• x402 version 2 payment flow
• Base mainnet payments (eip155:8453)
• Paid HTTP endpoints return valid x402 challenges with Bazaar metadata
• MCP and HTTP payment, execution, settlement, and delivery confirmed on-chain
• MCP Bazaar metadata advertises the public HTTPS MCP server URL
• CDP native MCP catalog indexing is not yet claimed as confirmed; upstream tracking: coinbase/cdp-sdk#764

MCP Tools

Decision verification

verificar_condicoes — $0.05 USDC

A paid decision-verification tool for agents.

Give it a public URL and one or more concrete conditions. It returns a decision based only on evidence extracted from that page:

• confirmado — the page clearly proves the condition.
• rejeitado — the page clearly contradicts the condition.
• incerto — the page does not provide enough evidence.

Each result includes the final source URL, page title, verification timestamp, condition-by-condition explanation, and a short quoted proof where available.

Example conditions:

• “The page identifies the seller.”
• “The product is available in Portugal.”
• “The page shows a price in euros.”
• “The document states that the service supports x402.”

This is designed for agents that need an evidence-based decision before taking the next action.

Shortened. The full README is on GitHub.