X402 Services

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)

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.

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.