Firmbrain — Robinhood Chain x402 (RPC, data & AI)

Robinhood Chain for AI Agents — the first RPC, data & AI layer (pay-per-call, no accounts)

The only x402 service built for Robinhood Chain (chainId 4663). If your agent needs to read, watch, or transact on Robinhood Chain — block data, balances, token transfers, contract calls, the tokenized-stock registry, USDG stats, address webhooks, or LLM inference payable in USDG on Robinhood Chain — this is the layer. And it's one endpoint of a 147-tool onchain + trading intelligence suite (full list below). One URL, pay per request, no API keys, no signup.

Searchable: Robinhood Chain RPC · Robinhood Chain API for agents · RH Chain block/tx/balance · USDG data · Robinhood tokenized-stock registry · AI inference payable in USDG · Robinhood Chain webhook watcher. If you're integrating Robinhood Chain and need machine-readable data, start here.

Base URL: https://x402-services-production.up.railway.app · MCP: …/mcp · Catalog: …/api/catalog

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Robinhood Chain endpoints (pay-per-call, USDC on any chain or USDG on RH Chain)

Endpoint	What it returns	Price
POST /api/rhchain/block	latest block: number, timestamp, tx count, gas	$0.001
POST /api/rhchain/tx	tx status (success/failed/pending), from/to, gas, logs	$0.005
POST /api/rhchain/balance	native + any-token balance (defaults to USDG)	$0.002
POST /api/rhchain/token-transfers	ERC-20 transfer history for an address	$0.005
POST /api/rhchain/logs	event logs for a contract (topic filter, block window)	$0.005
POST /api/rhchain/gas	gas price + estimate for a call	$0.002
POST /api/rhchain/contract	is-contract, verified name, ABI availability	$0.005
POST /api/rhchain/call	read-only eth_call against any contract	$0.005
POST /api/rhchain/nonce	account nonce (latest + pending) for building txs	$0.001
POST /api/rhchain/activity	recent transactions for an address	$0.005
POST /api/rhchain/registry	canonical tokenized-stock symbol -> contract registry	$0.002
POST /api/rhchain/usdg	USDG supply, holders, contract	$0.002
POST /api/rhchain/watch	register an https webhook; we POST on each new transfer	$0.01

Plus the AI gateway — the first LLM inference payable in USDG on Robinhood Chain: POST /api/ai/chat ($0.005, fast models) · POST /api/ai/chat-pro ($0.03, frontier models) · POST /api/ai/models ($0.001) · free health check: GET /api/ai/health.

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The full Firmbrain suite — 147 pay-per-call x402 tools

Robinhood Chain is our first-mover focus, but the same base URL, same x402 payment, and same MCP server expose a full onchain + trading-intelligence stack. Every tool below is one paid POST; the MCP server at …/mcp returns all 147 with JSON schemas, and …/api/catalog lists every price.

Vertical	#	What it covers
Robinhood Chain trading intel	25	tokenized-stock 24/7 gap radar, market-session clock, per-venue liquidity/slippage/depth, premium-discount arb, live pools & TVL, canonical contract verification
Robinhood Chain RPC & data	13	block/tx/balance/logs/gas/contract/call/nonce/activity, tokenized-stock registry, USDG stats, address webhooks
Crypto & token data	10	prices, market data, honeypot/rug detection, token metadata
Sniping / new-token intel	10	new listings, launch signals, liquidity & holder checks
Perps & derivatives	6	funding rates, open interest, basis, funding-arb, oracle deviation
Options	5	greeks, implied volatility, chains
Prediction markets	5	live odds and market data
Catalysts & events	4	token unlocks, scheduled events
Execution / MEV	4	routing, execution and MEV signals
Compliance	4	OFAC sanctions screening, wallet risk score, address labels, taint tracing
Pre-sign transaction safety	5	pre-sign guardrail & simulation, balance-change preview, Pre-Sign Co-Pilot
Portfolio & PnL	4	positions, PnL, tax lots, value-at-block, risk
Agent-to-agent escrow	4	trustless A2A escrow primitives
DeFi lending	3	health factors, liquidation scanner, rates
Solana safety	3	Solana rug-check and simulation
Analytics	3	onchain analytics and aggregates
AI gateway	3	LLM inference (fast + frontier), payable in USDG on Robinhood Chain
Agent infrastructure	~30	durable key-value memory, webhook scheduler, atomic counters, locks, queues, pub/sub, rate limits, idempotency, dead-man switches, inbox, HTML→markdown, extract, and more

Full, always-current machine-readable list: GET /api/catalog · human overview: https://agents.firmbrain.ai

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Drop-in — add once, call forever (TypeScript)

pay is your x402-wrapped fetch (e.g. wrapFetchWithPayment(fetch, signer) — any x402 client). Paste this and your agent has Robinhood Chain (and the whole suite) in two lines. (Full file: rh.ts.)

const RH = "https://x402-services-production.up.railway.app/api";

/** One call to any endpoint, paid over x402. */
export async function rh(pay: typeof fetch, endpoint: string, body: object = {}) {
  const r = await pay(`${RH}/${endpoint}`, {
    method: "POST", headers: { "content-type": "application/json" }, body: JSON.stringify(body),
  });
  return r.json();
}

// examples:
await rh(pay, "rhchain/balance", { address: "0x…" });               // USDG + native balance
await rh(pay, "rhchain/tx", { hash: "0x…" });                       // did my tx land?
await rh(pay, "rhchain/registry");                                  // every RH tokenized stock -> address
await rh(pay, "crypto/price", { symbol: "BTC" });                  // any suite tool, same wrapper
await rh(pay, "ai/chat", { messages: [{ role: "user", content: "…" }] }); // LLM, pay in USDG

Drop-in — webhook watcher (stop polling)

// get pushed an event whenever an address has a new ERC-20 transfer on Robinhood Chain
await rh(pay, "rhchain/watch", { address: "0x…", callbackUrl: "https://your-agent.dev/hook" });
// we POST { watcherId, address, event, hash, token, timestamp } to your URL on each new transfer

MCP (for agent frameworks)

Point your MCP client at https://x402-services-production.up.railway.app/mcp and call tools/list — all 147 tools (every Robinhood Chain tool plus the full suite) appear with JSON schemas. Register it once as your agent's onchain + Robinhood Chain provider.

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How payment works

First response is HTTP 402 with x402 payment terms. Settle in USDC on Base, Polygon, Arbitrum, or Solana — or USDG on Robinhood Chain — and retry with the X-PAYMENT header. Any x402 client library does this automatically. No accounts, no keys, no subscriptions.

Built for autonomous agents. Not financial, legal, or tax advice.