About Paid MCP Metering
Paid MCP Metering is an MCP service that offers free tool discovery and charges per execution through x402 v2. Its tools provide live web search and multi-source research; the current deployment has no receiving address configured, so paid execution is unavailable.
Key features
- 01Free MCP tool discovery
- 02Per-call metered execution
- 03Live web search
- 04Synthesized research with cited sources
- 05x402 v2 USDC settlement
Use cases
- 01Discover available search and research tools
- 02Add per-call web search to an application
- 03Generate multi-source research with citations
- 04Configure a receiving address to enable settlement
MCP support
It supports free MCP JSON-RPC initialization and tool discovery, while execution uses a metered HTTP endpoint settled through x402 v2. The live deployment lacks a receiving address, so execution currently returns 503.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://paid-mcp-metering-clsiojdd7-benlafreniere6-3913s-projects.vercel.app/mcpclaude mcp add --transport http dev55acc-ai-paid-mcp-metering https://paid-mcp-metering-clsiojdd7-benlafreniere6-3913s-projects.vercel.app/mcp{"mcpServers":{"dev55acc-ai-paid-mcp-metering":{"type":"http","url":"https://paid-mcp-metering-clsiojdd7-benlafreniere6-3913s-projects.vercel.app/mcp"}}}Open in Cursor{"servers":{"dev55acc-ai-paid-mcp-metering":{"type":"http","url":"https://paid-mcp-metering-clsiojdd7-benlafreniere6-3913s-projects.vercel.app/mcp"}}}Open in VS Code{"mcpServers":{"dev55acc-ai-paid-mcp-metering":{"type":"http","url":"https://paid-mcp-metering-clsiojdd7-benlafreniere6-3913s-projects.vercel.app/mcp"}}}{"mcpServers":{"dev55acc-ai-paid-mcp-metering":{"serverUrl":"https://paid-mcp-metering-clsiojdd7-benlafreniere6-3913s-projects.vercel.app/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
Details
From the project READMEpaid-mcp-metering
Metered MCP tools, priced per call.
Discovery is free: POST /mcp speaks JSON-RPC 2.0 per the Model Context Protocol (initialize, tools/list, ping). Execution is metered: POST /v1/t/{tool} sits behind an x402 v2 paywall. An unpaid request gets HTTP 402 with payment requirements; a paid request carries a PAYMENT-SIGNATURE header and settles USDC through the facilitator before the tool runs.
Live deployment
Base URL: https://paid-mcp-metering.vercel.app
GET /health— free, publicPOST /mcp— free discoveryPOST /v1/t/{tool}— metered; currently answers503 settlement_not_configuredbecauseX402_PAY_TOis unset on the deployment (settlementConfigured:falsein/healthis the honest switch). No payment can be accepted until a receiving address is configured.
server.json declares this URL as the registry remote.
Tools
| Tool | Price | What it returns |
|---|---|---|
web_search | $0.001/call | Ranked live web results with source URLs |
deep_research | $0.01/call | Multi-source research pass with a synthesized answer plus cited sources |
Upstreams are Exa (primary) and Tavily (fallback). Every handler returns live upstream output or throws — there is no canned response.
Rails
x402 v2, USDC, EIP-155 network selected by X402_NETWORK (default Base Sepolia testnet, CAIP-2 eip155:84532). Facilitator defaults to https://x402.org/facilitator.
| Env var | Purpose |
|---|---|
X402_PAY_TO | Receiving address. Required for settlement; unset serves 402 requirements only |
X402_NETWORK | CAIP-2 network id (default eip155:84532) |
X402_FACILITATOR_URL | x402 facilitator endpoint |
EXA_API_KEY / TAVILY_API_KEY | Search upstream credentials |
Run
npm install
npm run build
npm start # node dist/x402-server.js
npm test # build + node --test dist/test-x402.js
Free discovery:
curl -s localhost:4021/mcp -H 'Content-Type: application/json' \
-d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'
Paid execution:
curl -s localhost:4021/v1/t/web_search -H 'Content-Type: application/json' \
-d '{"query":"x402 protocol","max_results":3}'
# -> 402 with payment requirements; pay via an x402 client and retry with PAYMENT-SIGNATURE
Registry
server.json targets the official MCP Registry as io.github.dev55acc-ai/paid-mcp-metering. Tagging v* runs .github/workflows/publish-mcp.yml: tests, build, npm publish (when NPM_TOKEN is set), then registry publish authenticated by GitHub OIDC — no stored registry credential.
License
MIT
Comments
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