Gexno Web3

Gexno Web3 MCP

Free, no-signup on-chain lookups for AI agents. Two read-only tools: wallet profile and NFT metadata.

• Remote: https://api.gexno.com/mcp — Streamable HTTP, nothing to install
• npm: npx @gexno/web3-mcp — same tools over stdio
• Registry name: io.github.JanzenChen/gexno-web3

No API key, no signup, no wallet connection. Reads only.

Tool	What it returns
lookup_wallet	ETH balance, contract flag, outbound tx count, simple risk heuristics (ok / new_wallet / contract / eip7702)
lookup_nft	NFT metadata for contract + tokenId: name, description, image HTTP URL, IPFS gateway link, raw JSON (ERC-721 tokenURI and ERC-1155 uri)

Backed by the Gexno Web3 Agent API: https://api.gexno.com/api/web3

Use it (remote, nothing to install)

{
  "mcpServers": {
    "gexno-web3": {
      "url": "https://api.gexno.com/mcp"
    }
  }
}

Works with Claude Desktop, Cursor, and any MCP client that supports remote servers.

Discovery documents:

• server card — https://api.gexno.com/.well-known/mcp/server-card.json
• AI catalog — https://api.gexno.com/.well-known/ai-catalog.json
• OpenAPI — https://api.gexno.com/api/web3/openapi.json

Use it (npm, stdio)

npx -y @gexno/web3-mcp

Client config:

{
  "mcpServers": {
    "gexno-web3": {
      "command": "npx",
      "args": ["-y", "@gexno/web3-mcp"]
    }
  }
}

Requires Node.js >= 20. The stdio process calls the same public HTTP API.

Environment variables

Variable	Default	Purpose
GEXNO_API_BASE	https://api.gexno.com	API root, useful for self-hosted instances
GEXNO_TIMEOUT_MS	35000	Per-request timeout; NFT + IPFS resolution can be slow
GEXNO_INTERNAL_TOKEN	—	Only for self-hosted Gexno APIs that require it. Never commit a value.

Programmatic use

import { TOOLS, createApiGet, runTool } from '@gexno/web3-mcp'

const apiGet = createApiGet({ apiBase: 'https://api.gexno.com' })
const wallet = await runTool('lookup_wallet', { address: '0xd8dA...6045' }, apiGet)

Use it (local bundle, MCPB)

Download gexno-web3.mcpb from Releases and open it in Claude Desktop (drag onto the app, or Settings → Extensions).

What the output looks like

{
  "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
  "balanceEth": "5.7736",
  "isContract": false,
  "txCount": 5969,
  "risk": "eip7702",
  "eip7702": true,
  "delegation": { "address": "0xd1ea…", "verified": true }
}

EIP-7702 delegated EOAs are reported as risk: "eip7702" with isContract: false — they are still EOAs, they just carry a delegation designator. We parse the 0xef0100 prefix and checksum the delegate address, so a delegated wallet is not misreported as a smart contract.

Limits & behaviour

• Free tier: short-burst rate limit plus a daily cap per IP; no key required.
• Cached reads: wallet ~60s, NFT metadata ~5min. Repeat lookups are millisecond-scale.
• No signup, no tracking, no wallet connection. Reads only.
• Not an AML/risk score. Heuristics are intentionally simple.
• Errors surface as normal MCP tool errors; the process does not crash.

Development

npm install
npm run smoke    # live wallet lookup against the API
npm start        # run the stdio server directly

Test against a local API instead of production with GEXNO_API_BASE=http://127.0.0.1:3000.

Security posture and residual risks: HARDENING.md

Links

• Website — https://www.gexno.com
• Trust report — https://verifymcp.io/servers/janzenchen-gexno-web3/api
• Issues — https://github.com/JanzenChen/gexno-web3/issues
• License — MIT