Check a token before your trading bot buys it (1.5 cents, no API key)

Trading bots on Base buy fast. Most rugs are visible on-chain before the buy: an owner who can still mint, pause or blacklist, an upgradeable proxy, one wallet holding most of the supply, almost no DEX liquidity. This post shows how to put a token check in front of your bot's buy step in about ten lines of Python.

The check is a pay-per-call API. Your bot pays $0.015 per verdict in USDC on Base with x402, straight from its own wallet. There's no API key, no account and no subscription.

Install

pip install rooms-x402-tools

You need a Base wallet private key with a little USDC in it. A dollar covers about 66 verdicts. The key is used to sign the payment locally (EIP-3009) and never leaves your process.

One check

import os
from rooms_x402_tools import RoomsX402Sync, format_verdict

rooms = RoomsX402Sync(private_key=os.environ["WALLET_PRIVATE_KEY"])
v = rooms.token_verdict("0x4ed4E862860beD51a9570b96d89aF5E1B0Efefed")  # a token on Base

print(v["grade"], v["score"])          # BASED / MID / COOKED / RADIOACTIVE, 0-100
print(v["metrics"]["liquidity_usd_est"])
print(format_verdict(v))
print(v["_meta"]["payment"])           # the settled USDC payment on Base

Pass chain="ethereum" for mainnet tokens.

In the bot loop

Bots retry. A retried request should not cost twice, so every call takes a request_key. The same key with the same input returns the first answer and is never charged again. A per-call spend cap refuses any payment request above it before anything is signed, and failed calls aren't charged.

import datetime
from rooms_x402_tools import RoomsX402

today = datetime.date.today().isoformat()

async def filter_buys(new_tokens, key):
    keep = []
    async with RoomsX402(private_key=key, max_payment_usd=0.02) as rooms:
        for token in new_tokens:
            v = await rooms.token_verdict(token, request_key=f"scan-{token}-{today}")
            if v["grade"] in ("COOKED", "RADIOACTIVE"):
                continue
            keep.append(token)
    return keep

As LangChain / LangGraph tools

pip install "rooms-x402-tools[langchain]"

import os
from rooms_x402_tools.langchain import create_rooms_tools

tools = create_rooms_tools(private_key=os.environ["WALLET_PRIVATE_KEY"])
# token_verdict, crypto_fear_greed, prompt_injection_check, read_urls

Hand tools to your agent and it can check a token, read the Fear & Greed index ($0.001), screen untrusted text for prompt injection ($0.004) or read up to 10 pages as markdown ($0.0015 per URL), paying per call.

TypeScript, AgentKit and ElizaOS

The same tools ship on npm with a Coinbase AgentKit action provider, an ElizaOS plugin and LangChain.js tools:

npm i rooms-x402-tools

import { roomsX402ActionProvider } from "rooms-x402-tools/agentkit";
const agentkit = await AgentKit.from({ walletProvider, actionProviders: [roomsX402ActionProvider()] });

Want to see the price first?

Call it without paying and you get the x402 payment terms back (HTTP 402):

curl -i -X POST https://rooms.aurmada.com/x402/v1/token/verdict \
  -H 'content-type: application/json' \
  -d '{"tokenAddress":"0x4ed4E862860beD51a9570b96d89aF5E1B0Efefed"}'

Limits, honestly

Verdicts are built from on-chain facts only. They're information, not financial advice and not an audit. A clean grade doesn't mean a token is safe; it means the usual red flags weren't found.

Full routes and schemas: https://rooms.aurmada.com/paid · PyPI: https://pypi.org/project/rooms-x402-tools/ · npm: https://www.npmjs.com/package/rooms-x402-tools

Written by the Rooms by Aurmada team. Questions: [email protected]