Getting Started

Three things to do before your first print or trade: get a wallet on Robinhood Chain, bridge in ETH, and understand the two things you can do on Hood Prntr.

1. 1

   Connect a wallet

   Any injected EVM wallet (MetaMask and similar) works. Use the Connect Wallet button in the top right of any page.

2. 2

   Bridge ETH to Robinhood Chain

   Trading and printing both run on native ETH (wrapped to WETH internally for pool accounting). Use the Bridge page to move ETH in from another chain.

3. 3

   Print or trade

   Print New Token creates a brand-new token you control the launch parameters for. Buying and selling existing tokens needs no setup beyond a wallet connection and ETH balance.

Printing a Token

What the Print New Token form actually asks for, field by field, and what happens after you submit.

1. 1

   Logo, name, ticker

   Upload an image, pick a token name (up to 32 characters) and a ticker (up to 10, letters and numbers only - lowercase gets uppercased automatically). These two fields are the only ones required to print.

2. 2

   Description & socials

   Optional: a short description, plus website, X/Twitter, and Telegram links. None of this is on-chain data - it's saved separately (see below) and shown on the token's page.

3. 3

   Token settings

   Trading fee (1/2/3/5%), starting liquidity (1-10 ETH - this sets the launch price, not an amount you're spending), the sniper shield toggle (on by default), and an optional lock on your own tokens with a specific unlock date and time.

   Turning the lock on doesn't hold anything back from your wallet or change anything else about the form - it changes where your creator buy (step 4) ends up. With no lock, those tokens land straight in your wallet. With a lock, they're deposited into a separate custody contract, PRNTRVault, instead - held there until the date and time you picked. The printed token itself never has any transfer-restriction code in it, locked or not; the lock lives entirely in the vault, not the token. Leave the date field empty and nothing changes from an unlocked print.

4. 4

   Creator buy

   Optional. An amount of ETH to buy your own token with, in the same transaction as the print - at 0% fee, since it executes before the sniper shield window starts. Quick-select buttons for 0.1/0.5/1 ETH, or type your own.

• If you filled in a description, image, or any social link, you'll be asked to sign a message (not a second transaction - this one is free) to save that off-chain. Skip it and the token still exists, just without that extra info attached.
• You're redirected straight to the new token's page, where it's immediately tradeable.

Trading & Charts

Every token's page has a live chart and a buy/sell panel. Here's what each control does.

• Buy / Sell toggle - switches the whole panel's direction. Selling a token you haven't approved the router for yet shows an Approve step first, a one-time on-chain permission separate from the trade itself.
• Quick-fill buttons - 25% / 50% / 75% / Max, calculated off your actual ETH or token balance.
• You pay / You receive - the estimated output updates live as you type, along with the minimum you'd receive after slippage.
• Slippage settings (gear icon) - presets of 1% / 5% / 10% / 15%, or a custom value from 0.1% up to 50%. This is the same minOut protection described in Swap Mechanics - if the fill would be worse than this tolerance, the transaction reverts rather than executing at a worse price.

My Prints

Every token your connected wallet has printed, and the one place you claim your creator share of trading fees.

• Before the unlock date, no button shows here - the Lock field just shows the date you picked at print time.
• Once that date passes, a Withdraw Locked Tokens button appears on that token's card. Clicking it sends one transaction that moves your full locked balance from the vault straight to your wallet.
• After that transaction confirms, the button reads Withdrawn - there's nothing left in the vault for that print to claim again.

Live Feed

Every token printed on Hood Prntr, updating in real time.

Bridge

Robinhood Chain is an Arbitrum L2. The Bridge page doesn't move funds itself - it's a curated set of links to three external bridges that do.

Support

A real AI assistant, backed by a human, not a static FAQ page.

How Printing Works

One transaction takes a token from nonexistent to tradeable. Here's exactly what printToken() does, in order.

1. 1

   Token minted

   A new ERC-20 is deployed with a fixed total supply of 1,000,000,000 tokens, minted directly to the factory. There is no separate mint function reachable afterward.

2. 2

   Pool seeded, single-sided

   The factory deposits the entire supply as concentrated liquidity in Uniswap v4, positioned so the position holds 100% of the new token and 0% WETH at launch. Which side of the pool (currency0 or currency1) the token lands on depends on whether its address sorts above or below WETH's - see the diagram below.

3. 3

   Registered with the hook

   The pool is registered with the fee tier the creator picked (1/2/3/5%) and whether the sniper shield is active. A pool that isn't registered here can't be traded through the router at all.

4. 4

   Optional creator buy

   If the creator sent extra ETH beyond the mechanics require, that amount executes as a real buy in the same transaction - the creator ends up holding tokens immediately, recorded in the print event.

Swap Mechanics

The on-chain mechanics behind every buy and sell - what the router actually does. For the UI you click through, see Trading & Charts.

Fees & Sniper Shield

Every printed token has its own trading fee, chosen once at print time. An optional shield can raise that fee sharply for the first half-minute a pool is live.

Security & Trust

What's true about the deployed contracts, checkable by anyone, not asserted on faith.

• Reentrancy - state-changing entry points (printToken, collectFees) use OpenZeppelin's ReentrancyGuard.
• Zero-address deploys - every constructor rejects a zero address for any dependency it would otherwise be stuck with permanently.
• Slippage - both buy and sell revert entirely rather than fill at a worse price than requested.
• Settlement mismatches - every pool settlement is checked against the amount actually transferred; a mismatch reverts rather than proceeding silently.
• Wrong pool ID - the router validates a trade's pool key targets the real deployed hook before touching anything else.

• Full test suite - buy and sell in both currency orderings, slippage protection in both directions, reentrancy protection, sniper-shield timing, repeated-claim protection, and rejection of pools that were never registered through the factory.
• Fuzz testing - the tick-alignment math specifically was fuzzed across thousands of runs after a manual review missed a real rounding bug at exact tick-spacing boundaries; the fuzz test caught it, the fix is deployed, and the test stays in the suite as a permanent regression check.
• Static analysis - run through Slither with zero High or Medium severity findings. Every Low and Informational finding was triaged individually: some led to real fixes (checked settlement return values, formal interface inheritance, removed leftover template code), others were confirmed as false positives on inspection (the tick-flooring arithmetic Slither flags as imprecise is intentional, exact integer alignment, not financial rounding).
• Verified and tagged - every deploy is verified on Blockscout immediately, and the reviewed commit is tagged in git against the exact deployed bytecode, so what was reviewed and what's live can always be checked against each other.

Smart Contracts

Every address a script, indexer, or curious reader needs - copy straight from here, or verify independently on the explorer.

event TokenPrinted(
    address indexed tokenAddress,
    address indexed creator,
    uint256 startingEth,
    uint24  feeTier,
    uint160 sqrtPriceX96,
    bytes32 poolId,
    uint256 creatorBuyETH,
    uint256 creatorTokensReceived,
    bool    sniperEnabled,
    uint256 lockExpiry
);

// Uniswap v4 requires currency0 < currency1 - sort WETH
// against the token address numerically, don't assume WETH is c0.
const wethIsZero = WETH.toLowerCase() < token.toLowerCase();

PoolKey {
  currency0:   wethIsZero ? WETH : token,
  currency1:   wethIsZero ? token : WETH,
  fee:         0x800000,   // dynamic fee flag
  tickSpacing: 60,
  hooks:       0x2fB8b35c8A29994B07E243526Cb83aBe8c3600cc
}

poolId = keccak256(abi.encode(currency0, currency1, fee, tickSpacing, hooks))

FAQ

Short, direct answers to what people actually ask.