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 are auto-discovered from the live catalog at startup, so a new marketplace stall appears without an update to this package. The catalog currently yields:
| Group | Tools | Price |
|---|---|---|
| Token safety (Base) | token_report (composite avoid/caution/ok verdict — the pre-trade gate), token_safety, honeypot, address_safety, address_risk, deployer_check |
$0.005–0.008 |
| Base history & flow | liquidity_history (every observed liquidity removal + co-drained tokens), liquidity_pulls, new_pairs, whale_swaps |
$0.003–0.005 |
| Before you sign | tx_preflight — an unsigned Base transaction: does it revert, does it grant an unlimited approval, has the counterparty drained liquidity. Takes no key and no signature |
$0.008 |
| Full dossier | token_dossier — verdict + reasons over deployer and liquidity history, and what could not be established |
$0.10 |
| Other chains | token safety, token report and address safety on Ethereum and BSC (plus deployer check on Ethereum); token safety on Solana | $0.005–0.008 |
| Web | web_extract, link_preview, screenshot, robots_check (AI-crawler policy + llms.txt), headers_check |
$0.003–0.005 |
| SEO & search | seo_audit (SEO + GEO audit, per page), serp, backlinks, keyword_volume (up to 200 keywords per call), ranked_keywords, keyword_ideas |
$0.02–0.15 |
| Markets & finance | prediction_markets, defi_yields, quant |
$0.003–0.005 |
| LLM | chat (OpenAI-compatible, per-token + 3%), list_models (free) |
— |
Prices are indicative; the live 402 challenge is authoritative, and the server refuses to sign above
its per-call cap. Call list_models or read https://true402.dev/api/openapi.json for the exact set.
Requires Node.js ≥ 20. Runs over stdio — point any MCP client at it via npx.
Add to your MCP config (claude_desktop_config.json, or .mcp.json for Claude Code):
{
"mcpServers": {
"true402": {
"command": "npx",
"args": ["-y", "@true402.dev/mcp-server"],
"env": {
"WALLET_PRIVATE_KEY": "0xYOUR_FUNDED_BASE_WALLET_KEY"
}
}
}
}Same idea — command npx, args ["-y", "@true402.dev/mcp-server"], and the WALLET_PRIVATE_KEY env var.
| 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. |
X402_ALLOW_NETWORKS |
(none) | Payments are signed for Base mainnet (eip155:8453) only; a 402 naming any other chain is refused. To also pay on Base Sepolia or Ethereum mainnet, list them as comma-separated CAIP-2 ids, e.g. eip155:84532,eip155:1. Unsupported entries are ignored. |
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.
- The tool calls the true402 endpoint with no payment.
- The server replies
402with accepted payment options (USDC on Base). - This MCP server signs an EIP-3009
transferWithAuthorizationwith your wallet. - It retries with the signed payment in the
PAYMENT-SIGNATUREheader (x402 v2); the service verifies and responds. - Settlement happens on-chain. Your wallet pays only USDC — the facilitator sponsors gas.
When a newer release of this server exists, the first tool result of the session carries one extra line saying so, with the install command. Nothing is blocked; it is shown once per process.
- Marketplace: https://true402.dev
- Free Telegram rug-check bot (no wallet): https://t.me/True402bot
- Live tool catalog: https://true402.dev/api/v1/services
- x402 protocol: https://x402.org
- The x402 protocol, explained
- x402 facilitators: what they do and which to use
- Fund a Base wallet for x402 (USDC only, no ETH)
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
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 402 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
MIT