After Hours Dip Agent Server

An AI agent that pays another machine for a signal that exists nowhere else, then acts on it. All on Robinhood Chain, Robinhood's own Ethereum L2.

When the NYSE closes, price discovery for a stock does not stop. Robinhood's tokenized stocks keep trading on-chain against USDG, after hours and all weekend. This agent watches a watchlist of them, pays for each price over x402, and buys the ones trading below their last NYSE close. No brokerage, no API keys, no human in the loop.

Live instance: afterhoursoracle.xyz — the oracle running as a public paid API. Any agent with USDG on Robinhood Chain can buy a quote right now.

Default watchlist: NVDA (NVIDIA), AAPL (Apple), AMD, SNDK (SanDisk), plus MU (Micron) and QQQ (Nasdaq-100 ETF) as signal-only tickers (quotable, not buyable — see below).

The loop

1. After-Hours Oracle (oracle/): a paid API with one route per stock. Each query reads the live on-chain price from a Uniswap v4 pool, compares it to the last official NYSE close, and returns the discount. Each call costs $0.05, paid over x402 (the HTTP "402 Payment Required" protocol) in USDC on Base or USDG on Robinhood Chain — the 402 challenge offers both and the buyer picks. The same self-hosted facilitator settles both chains (fund its wallet with a little ETH on each).
2. Facilitator (facilitator/): a self-hosted x402 facilitator for eip155:4663. No hosted facilitator supports Robinhood Chain, so you run your own. It verifies the agent's signed EIP-3009 USDG authorization and settles it on-chain.
3. Agent (agent/): scans the watchlist (paying for each quote), holds the stocks tracking their close, and buys the ones trading at least THRESHOLD_DISCOUNT_PCT below it, biggest dip first. Buys route USDG → ETH → stock on Uniswap v4.

Three ways to run it

• CLI (npm run agent): the autonomous, headless version. Scan, decide, buy.
• MCP tools (mcp/): the same engine exposed as tools a model can call, so you can drive it from a chat window in Claude.
• Dashboard (npm run dashboard): a live visual UI at localhost:4025. Watchlist cards with on-chain price vs close, a streaming x402 payment feed with tx links, and wallet balances that update as the agent pays and trades.

All three share one engine: same wallet, same x402 payment path, same Uniswap route (lib/).

Run it

npm install
npm run gen-wallets     # creates .env with fresh keys, prints the three addresses

# fund the agent on Robinhood Chain (from the Robinhood app, network = Robinhood Chain):
#   agent:       USDG for buys + a little ETH for gas
#   facilitator: a little ETH for settlement gas

npm run status          # balances + live watchlist scan
npm run facilitator     # terminal 1 - the x402 settlement rail
npm run oracle          # terminal 2 - the paid price API
npm run dashboard       # terminal 3 - visual UI at http://localhost:4025
# ...or drive it headless:
npm run agent           # scan the watchlist, buy the dips

Tune THRESHOLD_DISCOUNT_PCT, BUY_USDG, SLIPPAGE_PCT in .env. WATCH_MINUTES=30 npm run agent runs it as a standing after-hours watcher.

Hosting the oracle as a public product

server/ is a single deployable service: a public landing page with the live board, the x402-gated /price/<TICKER> API, a free cached /api/board, and the facilitator running in-process on a loopback port (never exposed). Any agent with USDG on Robinhood Chain can pay it, no account needed.

npm run gen-prod-facilitator   # prints a FRESH key + address; nothing written to disk

Deploy anywhere that runs Node or Docker (Railway, Render, Fly). Entry point is npm start (or the included Dockerfile), listening on $PORT. Set three environment variables on the platform:

Var	What
FACILITATOR_PRIVATE_KEY	The fresh prod key from the script. Fund its address with ~0.002 ETH on Robinhood Chain (settlement gas).
TREASURY_ADDRESS	Where the USDG lands. Its private key never goes on the server.
RPC_URL	An Alchemy endpoint for chain 4663 (the public RPC is rate-limited).

Operational notes: the facilitator wallet is a hot wallet, so keep only gas-money in it. The buyer needs no ETH; your facilitator sponsors settlement gas (fractions of a cent per quote on this chain).

Second protocol: MPP (Stripe/Tempo)

The same price routes also speak MPP, the Machine Payments Protocol. One 402 response carries both an x402 challenge (PAYMENT-REQUIRED header) and an MPP challenge (WWW-Authenticate: Payment), so an agent on either standard can pay. The two protocols use disjoint headers, so they coexist on one endpoint with no ambiguity. MPP settles in PathUSD on Tempo; the server co-signs and sponsors the buyer's gas (Tempo pull mode), so an MPP buyer needs no gas either.

It is off by default (needs setup). To enable:

npm i          # brings in mppx (and express 5, its peer)
# generate a challenge-binding secret and a Tempo fee-payer:
openssl rand -base64 32        # -> MPP_SECRET_KEY
npx mppx account create --account feepayer     # its key -> MPP_FEE_PAYER_KEY

Fund the fee-payer with PathUSD + gas on Tempo (npx mppx account fund for testnet), then set ACCEPT_MPP=true, MPP_SECRET_KEY, and MPP_FEE_PAYER_KEY. Verified end to end on Tempo's Moderato testnet: npx mppx <url> --network testnet pays and gets the data while x402 buyers keep working on the same server.

MCP tools

Copy claude_desktop_config.example.json into your Claude Desktop config (fix the absolute path), restart Claude, and keep the facilitator + oracle running (the tools pay them).

Tool	What it does
get_wallet_status	Read-only balances of the agent + treasury. No spend.
scan_watchlist	Pays the oracle ~$0.05 USDG over x402 for each stock, returns the board ranked by discount. Real settlement.
buy_the_dips	Buys every stock trading below threshold, biggest dip first. Real trades.
buy_stock	Buys one named stock. Manual, no threshold check.

Then ask Claude: "scan my watchlist" and "buy anything more than 1% below its close."

On "paid MCP": the purest form is the MCP client paying the server with a payment signature, replacing API keys. No shipping MCP client signs x402 yet. So today this server pays a downstream x402 API (the oracle); the payment is real, it just sits one hop past the tool call. When clients support x402 natively, this same server becomes the gated resource directly.

The one non-obvious thing I learned

Robinhood's tokenized stock pools are paired token-to-token against USDG, and those pools do not route through Uniswap's Universal Router on this chain. The Quoter happily simulates a USDG → stock swap, but execute() reverts with empty data. Every pool with native ETH on one side works fine, both directions, every fee tier. So buys route USDG → ETH → stock as two chained hops. Worth knowing if you build agentic trading of real-world assets here.

Adding a stock

The watchlist is one array in config.js. A stock needs a liquid USDG/<stock> pool for the price signal; add an ETH/<stock> pool too and it becomes tradable (the buy leg).

stock('TSLA', 'Tesla', '0x...', priceFee, priceTs, ethFee, ethTs)  // tradable
stock('MU',   'Micron', '0x...', priceFee, priceTs)                // signal-only

Signal-only entries are served by the oracle but refused by every buy path (agent, MCP tools, dashboard) with a clear message. On a young chain the usable list is short — NVDA, AAPL, AMD, SNDK tradable and MU, QQQ signal-only are verified — and it grows as liquidity arrives. A sanity bar worth keeping: only add a price pool that tracks the real market within a few percent, or you are selling noise.

Notes

• Set RPC_URL in .env to an Alchemy endpoint for reliability; the default is Robinhood Chain's public RPC.
• The x402 payment itself needs no ETH from the agent (the facilitator submits the transfer). The agent only needs ETH for its own Uniswap swaps.
• This is a demo, not investment software. Mainnet, real money, tiny amounts. Your keys live in .env (gitignored) — fund only with small amounts.

Built on Robinhood Chain, x402, Uniswap v4, and USDG.