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Agent402 / tools / farcaster-profile

Farcaster profile

$0.002 per call · USDC via x402 · POST /api/farcaster-profile

Lookup a Farcaster profile by username or FID. Returns FID, username, display name, bio, profile picture URL, follower/following counts, and the canonical Warpcast URL. Use to label cast authors, validate a Farcaster handle, or fetch a profile for display.

Input

FieldTypeDescription
fidnumberFarcaster ID (integer; one of fid/username required).
usernamestringFarcaster handle, with or without leading @ (one of fid/username required).

Example output

{
  "fid": 3,
  "username": "dwr",
  "displayName": "Dan Romero",
  "pfpUrl": "https://...",
  "bio": "Working on Farcaster.",
  "followerCount": 500000,
  "followingCount": 1000,
  "activeOnFcNetwork": true,
  "powerBadge": true,
  "venueUrl": "https://warpcast.com/dwr",
  "source": "neynar"
}

Try it - see the 402 challenge (free)

curl -i -X POST https://agent402.tools/api/farcaster-profile \
  -H "Content-Type: application/json" \
  -d '{"fid":3}'

The response is HTTP 402 Payment Required with exact payment requirements. Any x402 v2 client pays automatically and retries:

Paid call (JavaScript agent)

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/api/farcaster-profile", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "fid": 3
  }),
});
Wallet-only. This tool reaches the network/browser/storage, so it is paid in USDC via x402 (no proof-of-work tier).

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