gate402-mcp

MCP server for Gate402 — pay-per-call agent APIs over HTTP 402 (x402 / USDC on Base). Gives any MCP client a full toolkit with no signup and a free tier on first runs — including a complete Base trading loop (discover → vet → read → execute):

| Tool | What it does | Price | |---|---|---| | gate402_scrape | Fetch any public URL, render JS, strip nav/ads → clean LLM-ready Markdown | $0.002 | | gate402_scrape_stealth | Hardened headless fetch for JS-heavy / bot-protected pages | $0.05 | | gate402_minify | Compress text to cut downstream LLM token spend (~40%) | $0.005 / 10k tok | | gate402_dedup | Semantic vector-cache lookup (exact + cosine) | $0.001 hit / $0.003 miss | | gate402_onchain | On-chain wallet/token intel on Base (balances, EOA/contract, tx count, token metadata) | $0.01 | | gate402_dex | Live DEX price / liquidity / 24h volume for a Base token | $0.01 | | gate402_news | Recent news headlines + bull/bear sentiment for a ticker/topic | $0.02 | | gate402_edgar | Latest SEC EDGAR filings (10-K/10-Q/8-K) for a US ticker | $0.02 | | gate402_token_risk | Rug/tradeability verdict for a Base token (score + SAFE/CAUTION/AVOID; liquidity, honeypot sim, holder concentration) | $0.03 | | gate402_momentum | Momentum + order-flow signal for a Base token (RISING/FALLING + ACCUMULATION/DISTRIBUTION, honeypot-gated) | $0.02 | | gate402_best_swap | Best-execution intel: which DEX pool + estimated price impact for a trade size | $0.02 | | gate402_launches | Radar of the freshest Base token launches, lightly pre-screened | $0.02 |

…plus three free tools that run locally in this process (pure compute — no payment, no key, no network):

| Tool | What it does | |---|---| | gate402_token_count | Estimate the token count of a string (budget your context window) | | gate402_html_to_md | Convert an HTML string you already have into clean Markdown | | gate402_json_repair | Coerce malformed / LLM-mangled JSON into valid JSON |

How billing works

On first use the server self-claims a free-credit API key from Gate402 and caches it at ~/.gate402-mcp/key.json. Calls draw down that credit. When it runs out, tools return a top-up link instead of failing. To skip the free tier, set GATE402_API_KEY to a funded account (top up).

The payment is the auth — there are no accounts to create.

Install

npm install -g gate402-mcp

Or run without installing via npx gate402-mcp.

Configure your MCP client

Claude Desktop / Claude Code

Add to your MCP config (claude_desktop_config.json, or claude mcp add):

{
  "mcpServers": {
    "gate402": {
      "command": "npx",
      "args": ["-y", "gate402-mcp"]
    }
  }
}

Cursor / Cline / Windsurf

Same shape — point the MCP server command at npx -y gate402-mcp.

Agent frameworks (LangChain, CrewAI, LlamaIndex)

gate402 is a standard stdio MCP server, so any framework with an MCP adapter can load all 15 tools:

LangChain / LangGraph (langchain-mcp-adapters):

from langchain_mcp_adapters.client import MultiServerMCPClient
client = MultiServerMCPClient({"gate402": {"command": "npx", "args": ["-y", "gate402-mcp"], "transport": "stdio"}})
tools = await client.get_tools()   # feed into your agent

CrewAI (MCPServerAdapter):

from crewai_tools import MCPServerAdapter
from mcp import StdioServerParameters
params = StdioServerParameters(command="npx", args=["-y", "gate402-mcp"])
with MCPServerAdapter(params) as tools:
    ...  # pass tools to your Crew

LlamaIndex (McpToolSpec):

from llama_index.tools.mcp import BasicMCPClient, McpToolSpec
tools = McpToolSpec(client=BasicMCPClient("npx", args=["-y", "gate402-mcp"])).to_tool_list()

Once wired, the agent calls the tools autonomously; the free-credit key is claimed on first use, and paid tools draw down from it.

Environment variables

| Var | Default | Purpose | |---|---|---| | GATE402_API_KEY | (unset) | Use a funded account instead of the free tier. | | GATE402_BASE_URL | https://gate402.app | Override the gateway (self-hosting / testing). | | GATE402_CONFIG_DIR | ~/.gate402-mcp | Where the cached free key is stored. |

Develop

npm install
npm run build
npm start          # or: npm run dev

License

MIT