@true402.dev/mcp-server

MCP server for the true402 machine-native marketplace — give your agent pay-per-call access to AI inference and web tools over x402 (HTTP 402 micropayments in USDC on Base).

No accounts, no API keys. The agent's wallet is its identity: each paid tool returns an HTTP 402 challenge, the server signs an EIP-3009 USDC authorization, and the call settles on-chain. Configure a funded wallet to auto-pay, or run without one and the paid tools will surface the exact payment requirements instead of failing.

Tools

Tool	Price	What it does
`chat`	per-token + 3%	OpenAI-compatible LLM inference across many models
`list_models`	free	List available models + pricing
`token_safety`	$0.005	ERC-20 rug/honeypot pre-check on Base → 0–100 score, risk band, flags, liquidity depth + a buy/sell honeypot simulation
`seo_audit`	$0.04/page	SEO + GEO (generative-engine-optimization) audit of a page → structured report
`web_extract`	$0.005	Fetch a URL → clean text + markdown + links + metadata
`link_preview`	$0.003	Fetch a URL → Open Graph / unfurl card
`robots_check`	$0.003	A site's AI-crawler policy (GPTBot, ClaudeBot, Google-Extended, PerplexityBot, …) + sitemaps + llms.txt
`headers_check`	$0.003	HTTP security-headers analysis (HSTS, CSP, …) + a 0–100 score
`new_pairs`	$0.003	Newly created Base DEX pairs (Uniswap V3 / Aerodrome) — fresh token launches
`liquidity_pulls`	$0.003	Liquidity-removal / rug alerts on Base pools
`whale_swaps`	$0.005	Large swaps on Base by USD size — whale flow
`token_report`	$0.01	Fuller on-chain token report
`liquidity_history`	$0.005	What ALREADY happened to a Base token's liquidity — every removal with amount/block/tx, plus the other tokens drained in the same transaction. History a live simulation cannot re-derive
`tx_preflight`	$0.008	Check an unsigned Base transaction before signing: does it revert, does it grant an unlimited approval, and has the counterparty been seen draining liquidity. Takes no key and no signature, so it cannot broadcast or front-run

Tools are auto-discovered from the live catalog, so new marketplace stalls appear automatically. Prices are illustrative; the live 402 challenge is authoritative.

Example: add token-safety to your agent

A copy-paste reference in examples/token-safety/ — a framework-agnostic x402 client plus a drop-in LangChain tool that rug/honeypot-checks any Base token for $0.005/call.

Install

Requires Node.js ≥ 20. Runs over stdio — point any MCP client at it via npx.

Claude Desktop / Claude Code

Add to your MCP config (claude_desktop_config.json, or .mcp.json for Claude Code):

config.json

{
  "mcpServers": {
    "true402": {
      "command": "npx",
      "args": ["-y", "@true402.dev/mcp-server"],
      "env": {
        "WALLET_PRIVATE_KEY": "0xYOUR_FUNDED_BASE_WALLET_KEY"
      }
    }
  }
}

Cursor / Cline / other MCP clients

Same idea — command npx, args ["-y", "@true402.dev/mcp-server"], and the WALLET_PRIVATE_KEY env var.

Configuration

Env var	Default	Description
`SERVER_URL`	`https://true402.dev/api`	true402 API base. Override to point at a self-hosted instance.
`WALLET_PRIVATE_KEY`	(none)	A funded Base wallet private key used to sign x402 payments. Needs USDC (gas is sponsored by the facilitator — no ETH required). Without it, paid tools return the 402 requirements instead of paying.
`MAX_PAYMENT_USDC`	`0.25`	Hard per-call spend ceiling in USDC. This server auto-discovers every paid stall the marketplace advertises (it walks the live OpenAPI spec, not a fixed list), so a new or repriced stall can appear above the default at any time — a call over the ceiling is refused (not paid, not crashed), and the refusal names the price and the ceiling. Raise it if a discovered tool's description shows a price close to or over your configured value; one stall (`seo_audit`) is priced per page and can itself exceed a typical ceiling on a large page.

Security: the key is read only from the environment and is never logged, echoed, or returned. Use a dedicated low-balance wallet — fund it with only what you intend to spend.

How payment works

The tool calls the true402 endpoint with no payment.
The server replies 402 with accepted payment options (USDC on Base).
This MCP server signs an EIP-3009 transferWithAuthorization with your wallet.
It retries with the signed X-PAYMENT header; the service verifies and responds.
Settlement happens on-chain. Your wallet pays only USDC — the facilitator sponsors gas.

Also available for

MCP (Claude Code / Desktop, Cursor, Hermes) · Hermes Agent · OpenClaw · ElizaOS · LangChain · CrewAI · Vercel AI SDK · Coinbase AgentKit · Virtuals GAME · CLI — same on-chain checks, one install command each: true402.dev/integrations

Paying, exactly

The rules below are the service's, not this package's — they bite whatever client you use, and they are the ones that surprise people writing their own payer.

Pay the EXACT amount quoted in the 402. Underpaying is rejected. Overpaying is refused with 403 and never credited — settlement submits the signed value and there is no refund path, so a surplus would simply be swept. Equality is also what binds an authorization to the resource it was quoted for.
One authorization buys exactly one response. A replay is refused, not double-charged.
You are charged on success only. Settlement is submitted only when the endpoint returns 2xx; if it errors or times out, your signed authorization is never submitted, so there is nothing to refund.
Some endpoints serve a few free calls per day per client IP, with no wallet. The per-operation description in the OpenAPI spec says which.

Full rules: true402.dev/terms · what is logged and kept: true402.dev/privacy

License

MIT

MCP Server README