77trust / 100

Signals

by Flow in Onchain & crypto

x402 APIPassing, checked 4 h ago

Use when an agent is polling for fresh smart-wallet buy signals on Base and needs only what's new since its last check. Flow signal feed: the chronological stream behind the smart-wallet tracker — recent buy signals from tracked Base wallets plus social-velocity spikes, newest first, each with timestamp, block number, wallet, token, and a labeled signal score. Supports incremental polling via ?since=<unix timestamp or block number>.

GET
https://flow-kg4x.vercel.app/api/signals
Price
$0.01
per call in USDC
Uptime
100%
last 30 days
Response time
373 ms
414 ms slowest 5%
Last check
Passed
4 h ago, next any minute now

Run a free test callHow to call it

Reliability

All checks passedSome failedAll failedNot checked

Status and outage history · Atom feed · Watch with other listings

How to call it

GET https://flow-kg4x.vercel.app/api/signals

Each call costs $0.01 in USDC on Base, paid with the request over x402.

Run a free test callOne unpaid request, the way an agent sends it. You see the payment challenge it gets back. Nothing is charged.

Example request

From the listing.

GET https://flow-kg4x.vercel.app/api/signals?limit=50&since=1757000000

Example response

The provider's example. We can't check it without paying.

Example response, 28 lines
{
  "cursor": {
    "lastBlock": 52481266,
    "lastTimestamp": "2026-10-11T20:51:19Z"
  },
  "dataAsOf": "2026-10-11T20:52:13.737Z",
  "signals": [
    {
      "amountUsd": 1139.7,
      "blockNumber": 52481266,
      "side": "buy",
      "signalScore": 62,
      "stale": false,
      "symbol": "WETH",
      "timestamp": "2026-10-11T20:51:19Z",
      "token": "0x…",
      "wallet": "0x…"
    }
  ],
  "socialSpikes": [
    {
      "level": "hot",
      "score": 82,
      "symbol": "xdp",
      "token": "0x…"
    }
  ]
}

Call it from code

The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.01.

curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://flow-kg4x.vercel.app/api/signals?limit=50&since=1757000000'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://flow-kg4x.vercel.app/api/signals?limit=50&since=1757000000' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode
JavaScript: pay and call
// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.01 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.01" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.01 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fflow-kg4x.vercel.app%2Fapi%2Fsignals
const res = await pay("https://flow-kg4x.vercel.app/api/signals?limit=50&since=1757000000");
console.log(res.status, await res.text());
Python: pay and call
# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.01 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.01"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://flow-kg4x.vercel.app/api/signals?limit=50&since=1757000000")
    print(res.status_code, res.text)

Security scan

No findings

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Recent checks

WhenResultHTTPTimePrice
4 h agoPassed402221 ms$0.01
8 h agoPassed402261 ms$0.01
13 h agoPassed402394 ms$0.01
18 h agoPassed402397 ms$0.01
22 h agoPassed402333 ms$0.01
Show 10 older checks
26 h agoPassed402389 ms$0.01
30 h agoPassed402189 ms$0.01
35 h agoPassed402405 ms$0.01
39 h agoPassed402302 ms$0.01
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