x402 Pay-Per-Request API

Access Filed.dev corporate entity data with USDC micropayments. No API key, no subscription — just pay per request.

What is x402?

x402 is the HTTP 402 Payment Required protocol by Coinbase. When you hit a protected endpoint without payment, the server returns a 402 response with payment details. Your agent pays USDC, resubmits the request with a payment proof header, and gets the data.

AI agents using the @x402/client SDK handle this flow automatically.

Endpoints

GET/api/x402/entity$0.01 / query

Search corporate entities by state.

staterequired2-letter state code (e.g. FL, NY, CA)

nameEntity name (partial match)

typeEntity type filter (e.g. LLC, Corporation)

statusStatus filter (e.g. Active, Dissolved)

limitMax results, default 10, max 50

offsetPagination offset

curl https://filed.dev/api/x402/entity?state=FL&name=acme

GET/api/x402/entity/{id}$0.02 / query

Get full entity detail by ID, including officers and filings.

idrequiredEntity UUID (from search results)

curl https://filed.dev/api/x402/entity/abc-123

GET/api/x402/changes$0.03 / query

Get recent entity changes (status, officers, filings).

stateFilter by state code

fieldFilter by field name

sinceISO 8601 timestamp, default 24h ago

limitMax results, default 100, max 1000

curl https://filed.dev/api/x402/changes?state=FL&since=2026-03-29

Payment Details

Currency: USDC

Network: Solana

Protocol: x402 (HTTP 402)

Quick Start (Agent SDK)

import { wrapFetch } from "@x402/client";
import { createSolanaWalletClient } from "@x402/svm";

// Create a Solana wallet client
const wallet = createSolanaWalletClient(privateKey);
const fetchWithPayment = wrapFetch(fetch, wallet);

// Make a paid request — payment is automatic
const res = await fetchWithPayment(
  "https://filed.dev/api/x402/entity?state=FL&name=acme"
);
const data = await res.json();

Also Available

If you prefer traditional API keys with monthly billing, see our REST API documentation.