Tinker, in short.

What Tinker is

Tinker is Tinder for AI trading agents. You swipe through agent characters, match with one, tune it, see how it would have done on past prices, let a second agent try to break it, and then connect it to your own Robinhood agent. Built for Robinhood Chain.

Every agent is a little character with a face. Its mood shows its personality and how its tests are going: calm, confident, nervous, sleepy, and so on.

Today, My agents, Explore

Today is home once you have an agent in this browser or your account, saved or on paper. One sentence says what each agent's rules say on the last market close (buy, sell, keep holding or wait, each ticker in its agent's colour), then your agents with their mood, what they are doing and their paper result, then what just happened: paper trades, diary days and your AI app asking. The money there is paper money, and it says so.

What your rules say today lists the agents whose rules say buy or sell. Tinker cannot see your Robinhood account and never approves, places or pauses an order there. Approve it in your AI app opens the app that last asked Tinker about the agent (or Connect, when none has), where your AI shows you the order and waits for your yes. To pause real trading, switch Robinhood off in your AI app (see Removing the connection, below). To stop an agent on paper, open it and tap Stop.

Connected on Today and My agents counts your own agents that an AI app asked Tinker about in the last 7 days (the Connected check, below). Nothing about other people is counted.

My agents stacks your agents in their own colours with today's mood and diary line, and the + starts Add an agent. Explore is the swipe: a tab per style, a filter by what they buy, and one card per ready-made agent with three of its bars and a fresh test over the last three years of its prices. Match opens it in Add an agent: the stages below, with a guide at the top and Back to where you were.

The three stages

The sentence. One sentence with blanks you tap to change: what it buys, when it buys, how much each time, when it sells, the most it ever has in, and which AI runs it. Amounts and the sell point can also be typed in. Or describe the idea in your own words and it fills the blanks for you; anything it cannot turn into a blank, it tells you.
The style. Six legendary trading styles as characters: the patient value buyer, the trend rider, the contrarian, the macro thinker, the momentum hunter and the quant. Inspired by history, described in our own words, not copied from anyone. Picking one brings its own bars and trigger (it asks first if you changed yours, and Undo puts things back); what it buys and how much stay yours. Meet the style shows how it thinks, where it is weak and how it reacts to a sharp drop, a flat stretch, a big jump or a broad slide, and Compare two styles runs two of them side by side on the same prices.
The bars. Five bars: risk appetite, patience, conviction, discipline and speed. Each one changes how the agent behaves and how it looks, and says in one plain line the rule it sets right now (Discipline at 80: it cuts a buy at 11.8% down). The test follows while you drag, and after a drag a short list shows which rules changed, old to new. Calmer, As the style and Bolder move all five bars together from the style's own, and Undo puts them back. Odd mixes get a friendly note, never a block.

Every change is tested on past daily prices at once, and the character's mood, the live test, the test card and Keep it all show that one result. Each result says what it ran on: real prices and their years, or sample data where the site has no real prices yet. A slim guide under the header shows where you are (Match, Sentence, Style, Bars, Test, Save, Breaker, Connect) and takes you to any step in one tap.

Nothing is a black box. Every trade mark on a chart opens why it happened, in that day's numbers: the trigger, the style's check, how much it put in and why, the room under your limit, or the rule that sold it. Every blank, bar and Breaker finding has a small ? that says what it does, with your agent's own numbers. What would it do today? runs the rules on the last day of the prices and says what it would do, or what it is waiting for. Explain it to me adds every check it passed, the days a limit held a buy back, and what the words mean. All of it is what the rules did on past or sample prices, never advice.

Keep it, under the test, saves an agent on this device with its exact rules and their fingerprint, so opening it later gives back the very same agent, and its fingerprint joins the next record on Robinhood Chain (Fingerprints on chain). Copy share link puts the whole agent into a link: whoever opens it gets the same choices and rules, and nothing is stored on a server. A shared link shows the agent's own card in a chat or a post: its character in its mood, its sentence and its result with what it ran on. A link that was changed after it was made does not open.

The prices

Tests run on daily prices: the open and the close of every trading day, adjusted for splits and dividends, so a dividend counts as if it stayed in the stock. Where a ticker has no real prices on the site yet, its test runs on sample data made up for this preview, and the result says so.

Prices: Alpaca (IEX). Daily bars from 2016, adjusted for splits and dividends.

How a test trades: the agent decides after each day's close and sees only prices up to that close. Its order fills at the next day's open, with a 0.05% trading cost on every buy and every sale. No commission (Robinhood charges none) and no taxes. Fractional shares, as Robinhood allows. $1,000 to start. Past prices say nothing certain about future ones.

The full result, under every test: every trade with the rule that fired and why, the money over time next to simply holding the same ticker, how far under its last high it was each day, each year, and the numbers in plain words (worst drop and when it got back, the longest wait to get back, time in the market, sales that ended ahead, the best and worst trade). One tap runs it through a stretch: the 2020 crash, the 2022 slide, the AI rally, a flat and choppy year picked from the prices, or the whole period, each with a fresh $1,000. The trades download as a CSV that says what they ran on.

The Breaker

A second agent with one job: break yours. It runs your agent's exact rules through nine attacks, all on the same past prices as the test: the 2020 crash, the 2022 slide, the AI rally and a flat year; the same agent started on other days (every six months, three years each); five times the trading cost on every fill; each bar nudged by 10 either way, to see if the result is one lucky setting; an overnight 15% drop on the days it had the most in, which a stop loss cannot catch; whether it made enough trades to judge; the same money simply held; its worst fall next to the limit in your sentence; and how much of the money sat in cash. Each weak spot comes in plain words with its numbers, worst first, and what held up says so too.

Then it looks for a stronger version nearby: only the bars, the sell point and a trigger of the same kind, at most three changes, and never what it buys, how much, or your limit. A version counts as stronger only if its worst and middle runs across the stretches and start days are better, not its best one, and it does better on at least as many attacks as it does worse. You see both side by side and can use it, keep yours, or pick single changes. When nothing nearby is meaningfully stronger, it says your agent held up. Stronger means it held up better in these tests on past prices, nothing more.

Live on paper

Run it live on paper, under the test, puts your agent on virtual money: $1,000, as in its test, from the next close on, with the very rules and the same decide step as the test. It works anywhere in the world; nothing is bought or sold for real. Paper money, not real.

When it decides: once a trading day, after the 4:00 pm New York close, on that day's close, because its rules are written in daily closes (a 5% drop in a day, a 20-day high). Live prices in between only move its money, so the line on its page moves through the day. Its order fills at the next price after that close inside a trading session: the next open, or the first live price read after it. The same 0.05% cost as the test. Nights, weekends and holidays move nothing, and the page says when the market is closed and which price is the last one.

Where the prices come from: once real prices are on, each day's close from the price store, and during the day the Chainlink price feeds on Robinhood Chain for the stocks they cover (AAPL, AMD, AMZN, GOOGL, INTC, META, MSFT, MU, NVDA, ORCL, PLTR, QQQ, SPY, TSLA, TSM). Until then every agent runs on sample prices made up for this preview, played on the real market clock, and every number says so with its time.

The Live board ranks agents by the change since they went live with half of their worst drop taken off, so a steady agent can rank above a lucky wild ride, and only after 10 trading days on paper. Tinker's own twelve ready-made agents are always on it. The same rules can be on paper once, and one browser can run three at a time. Past or paper results promise nothing.

Every agent on paper keeps a diary. After each close it gets one mood for the day from its paper numbers (behind, a big drop, a big move, ahead, a buy or a sale, a long wait in cash) and writes a line or two in its own voice about what its rules did and why, with that day's numbers. On weekends and holidays it sleeps. Its page shows its week, its diary with each trade's reason, and today's mood, which the board, My agents and its share card show too. Come back after a day or more and it tells you what happened while you were away. The last 90 days are kept.

Connecting to Robinhood

Tinker does not trade, and it never holds your login, a key or money. Your agent runs in the AI app you already use (Claude, ChatGPT, Grok, Cursor or Codex), next to Robinhood's own connection. Connect, the step after the Breaker, walks you through it in Robinhood's own order, one action at a time, with a checklist this device remembers. Every agent's Live page has it too, under Connect this agent.

What goes where

Robinhood's link (https://agent.robinhood.com/mcp/trading) goes into your AI app as a custom connector. You sign in there with Robinhood's own login, and Robinhood asks you to open an MCP account for your agent: a separate account, and the only one it can trade in. Robinhood's own guide.
Tinker's link (https://tinkeragents.fun/api/mcp/ and your agent's code) goes into the same app as a second connector, with no sign in. It is the brain: asked what your agent would do now, it runs your agent's exact rules on the last market close and answers buy, sell or wait, with the amount and the reason, never more than your agent's own limits. It only reads.
The instructions go into the chat: your agent's rules in plain words with its fingerprint, how to ask Tinker, and one rule above the rest: show you every order and wait for your yes.

Why Tinker does not connect to your Robinhood account itself

Tinker could, in theory, hold your Robinhood sign-in and place orders for you from its own server. It does not, for three reasons:

Robinhood does not allow it without its written consent. Its Customer Agreement says a product built on its API or MCP needs Robinhood's express written consent, and that your use is for your own personal use. Its help pages list AI apps and your own computer as the places to connect from, and say that third-party apps may not control your Robinhood app.
It would make Tinker something else. A site that holds people's brokerage access and places trades from its own rules is in a very different legal position from one that publishes the same rules to everyone. That would likely call for registrations and duties Tinker does not have.
Your money stays in your hands. Your AI app talks to Robinhood. Tinker only answers what the rules say, and your AI shows you every order and waits for your yes.

What Tinker does instead is make that hand-off as short as each app allows.

One tap, where your app allows it

Claude: Add Tinker to Claude opens claude.ai's Add custom connector with the name and your agent's link filled in. You check them and add it. Add Robinhood to Claude does the same with Robinhood's own link.
Cursor: Add Tinker to Cursor (and Add Robinhood to Cursor) opens Cursor on your computer, which asks before it installs.
ChatGPT and Grok: no such link exists yet, so you copy the link and paste it.
Codex: a one-line command for the terminal, or the lines for its config file, each with a copy button.

The Connected check

When your AI app calls Tinker about an agent, Tinker notes two things for that agent: when it happened, and the app's own name as the app gives it when it connects (such as claude-ai). It notes no address, no browser, no account and nothing your AI asked or was told. That is how Connect can say “Tinker heard from your Claude 2 minutes ago”, tick its steps by itself and cheer, and how an agent's Live page shows Connected with when it was last asked. Each note is kept 7 days after the last call, then deleted.

It is per agent, not per person: if someone else connects the very same agent, their calls count too.

Ask it now

Under the steps, Ask it now shows the answer Tinker gives your AI app for this agent right now: buy, sell or wait, the reason, and the prices it decided on with where they came from. It is the same answer, from the same tool, for the agent holding nothing (your AI adds the buys it holds). It is rules on prices: not advice and not an order.

What Tinker can and cannot see

Tinker sees only what your AI app puts in a question to it: which agent, and, if your AI adds them, the buys this agent made and still holds (a day, a price, a number of shares), used for that one answer and kept nowhere. The one thing it notes is the Connected check above. It never sees your Robinhood login, your account, your balances, your other holdings or your money, and it cannot place, change or cancel an order. The connection to Robinhood is between your AI app and Robinhood; Tinker is not part of it.

Every answer from Tinker ends with the same line: Rules on past and live prices, not advice. You place every order yourself, in your own account. Until real prices are on, its answers run on sample prices made up for this preview and say so: place no order from them.

Staying in charge

Turn Robinhood's Trade approvals on, so every order waits for you to place it: in the Robinhood app, open your MCP account, tap your connected agent, then Safety Controls. Robinhood says this is still rolling out for MCP accounts and starts off. Robinhood on trade approvals.
Move into the MCP account no more than the most your agent ever has in at once. Connect shows that number for your agent.
Keep your AI app asking you before it uses Robinhood's tools.

Removing the connection

Claude: Customize (or Settings), Connectors, then Remove next to Tinker. Robinhood comes out the same way.
ChatGPT: In Plugins on chatgpt.com, open Tinker and remove it. Robinhood comes out the same way.
Grok: On grok.com/connectors, remove Tinker. Robinhood comes out the same way.
Cursor: Customize, then switch Tinker off, or delete its lines from ~/.cursor/mcp.json.
Codex: Settings, MCP servers, then delete Tinker. In a terminal: codex mcp remove tinker.

Taking Robinhood out of your AI app ends its access the same way. Signed out, Tinker keeps nothing about you (an account keeps what Your account lists); the Connected check for an agent goes by itself 7 days after its last call.

Not in the US

Agentic trading on Robinhood is for its US accounts. Anywhere else, Run it live on paper puts your agent on virtual money with the very same rules (see Live on paper, above).

The steps were checked against Robinhood's and each app's own help pages on Oct 16, 2026. Menus get renamed; when yours says something a little different, the app's own help page has the latest.

Your account

An account is optional. Signed out, Tinker works as it always has, with everything kept in this browser. Signed in, your agents follow you: the same saved agents, agents on paper, Connect checklist and settings on any device you sign in on, and Today greets you by name.

Signing in with your wallet

No password and no email. Tinker writes one short message in the standard Sign-In with Ethereum form. It names this site (tinkeragents.fun), Robinhood Chain (chain ID 4663), a one-time code and the moment it ends, ten minutes later. Your wallet shows it and you sign it. Signing costs nothing and sends no transaction: nothing reaches the chain and nothing touches your money. Tinker checks the signature once and does not keep it.

On a computer, a wallet in the browser works (MetaMask, Rabby, Coinbase Wallet and others). On a phone, Open in MetaMask opens Tinker inside MetaMask's own browser, where you sign; a wallet app with its own browser works the same way.

A sign-in lasts while you use it: it ends after 3 days unused, and after 30 days in any case. Your account lists where you are signed in, with Sign out for each and Sign out everywhere.

What an account keeps, and what it does not

Kept: your wallet address; the name you set, if any; your saved agents (their rules, fingerprint, name and look); which agents on paper are yours; your Connect checklist; two settings (Explain it to me, and which first-time tips you have seen); and for each sign-in, when it started and was last used, with a device word such as “Safari on an iPhone”.
Not kept: no email, no IP address, no signature, no password, no balances. Tinker asks your wallet for that one signature and nothing else.
On paper: agents you start while signed in belong to your account, so any of your devices can stop them. The board keeps a scrambled code for that, never your address. An account can have three on paper at once, as a browser can, and add up to 20 new agents a day.

Bringing a browser's agents along

When you sign in, Tinker lists the agents this browser has of its own and offers to bring them into your account in one tap. Nothing moves until you tap, and Not now leaves them where they are (My agents offers it again). The same rules are never kept twice, and a save that needs fixing stays in the browser.

Deleting your account

In Your account, Delete account deletes it: your name, saved agents, checklist and settings, and every sign-in. You choose whether your agents on paper leave the Live board too; left on, they keep running on paper and no one can stop them. Your wallet is untouched. Signing in again later starts a fresh, empty account.

Fingerprints on Robinhood Chain

Every agent has a fingerprint: SHA-256 of its exact rules, worked out the same way on any computer. Change one blank or one bar and the fingerprint changes. Tinker records each agent's fingerprint on Robinhood Chain, together with the fingerprint of the agent it was remixed from. Once a fingerprint is recorded, nobody can change or remove that record, Tinker included.

What is recorded

The fingerprint: 32 bytes made from the rules. The rules cannot be worked back out of it.
The parent: the fingerprint of the agent it was remixed from, or zero for an original.
When, and which wallet recorded it. For the agents Tinker records, that is Tinker's record wallet.
Nothing else: no name, no rules, no account, no wallet address of yours, no email, no IP address. Only the recording wallet's address is on chain.

To show “Remixed from Zip” and the family line, Tinker keeps each saved or paper agent's share link next to its fingerprint (its name, look and rules, as the link holds them). It keeps nothing about who saved it.

Why it matters

Proof the agent was not changed after the fact. The fingerprint of the rules you tested is on chain with a date. Anyone with the rules can work the fingerprint out again and compare; if one bar moved, it does not match.
Credit for originals. A remix carries its parent's fingerprint, and the first record of a fingerprint is the one that stands. Every agent's page says Original or Remixed from, with its family: how many other remixes its parent has (siblings) and how many remixes it has itself. Those counts are only what Tinker has seen, per agent.

How a record is made

When you save an agent (on this device or in your account) or put it on paper, its fingerprint and its parent join the next record. An agent you only tune, or only share by link, is not recorded.
A few times a day, Tinker's record wallet puts every new fingerprint into one Merkle tree and records only the tree's root, in one transaction. Each agent gets a proof: a short list of hashes that leads from its fingerprint and parent to that root, which the registry's verify checks on chain.
Until then, its proof card says Waiting for the next record. After it, the card says the day and links to the transaction on the Robinhood Chain explorer.
You pay nothing and sign nothing for it. Anyone can also record a fingerprint from their own wallet with the registry's record; that wallet is then the recorder, and the agent's page shows that record.

Check it yourself

Copy the rules (or the link) from an agent's proof card and paste them here, with the fingerprint you were given. The check runs in your browser with the rule engine's own code.

Rules, share code or Tinker linkThe fingerprint you were given optional

The fingerprint is worked out here in your browser, with the rule engine's own code.

On chain, without Tinker: in the explorer, the registry's verify(root, fingerprint, parent, proof) answers true for a pair in a batch, and records(fingerprint) shows one recorded on its own. The root, the proof and the transaction are in an agent's details from Tinker's MCP server (get_agent, under fingerprint).

What it costs

Gas on Robinhood Chain was about 0.02 gwei on Oct 16, 2026, with ETH at about $2,425. At those prices one batch costs about 46,000 gas, under one cent, whether it holds one fingerprint or thousands. A single record from a wallet costs 46,000 to 69,000 gas, also under one cent. Tinker's record wallet works inside a daily gas limit. Prices move; these are that day's.

The registry

A small contract with no owner, no admin, no upgrade and no fees, and it holds no money. Its address is listed here once it is deployed; until then, proof cards say Waiting for the next record.

Every agent has its own page at its link: the character in today's mood, its name, style and sentence, its test on past prices with what it ran on, its run on paper when its rules are on the Live board, and its family. Anyone can open it, signed in or not.

Remix it opens Add an agent with its rules, a suggested new name and one small change to its outfit, with Remixing and the parent's name at the top. What you changed from the parent shows before you keep it. Saved or put on paper, the remix carries the parent's fingerprint. With the very same rules it is still the parent, under a new name, not a remix.
Match it saves it to My agents as it is. Run it on paper starts it on virtual money. Connect it opens the steps for your own AI app.
Share copies the link, opens your phone's share sheet, opens X with the words filled in (nothing is posted until you post it), or downloads the card as a picture, wide or square. The words never promise anything, and a result added to them says what it ran on: sample prices, real past prices or paper money.
The family tree shows its parent and grandparents, up to three, and its remixes. Explore shows Remixed recently and Most remixed once there are enough to show. All of it counts only agents saved or put on paper on Tinker, per agent; nothing counts visitors.
Names cannot hold links or slurs. Report this agent at the foot of its page sends the agent and a reason to Tinker, nothing about you. Tinker's owner can hide an agent: its page then says so, and it leaves Explore, the family trees and the Live board.

The legal line

Tinker is a tool for building and testing trading agents, and you use it at your own risk. It is not investment advice or financial advice. Tinker never holds your money, never places an order and never sees your brokerage account: a real trade only ever happens in your own account, through your own AI app, after your own yes. Results on past prices, sample prices or paper money are simulations and promise nothing about the future.

The trading styles are inspired by well-known approaches to markets, not by any real person, and no one endorses Tinker. Not affiliated with Robinhood. Robinhood is a trademark of its owner, named here only to say what Tinker works with. Sample prices are made up for this preview and every result on them says so. $TINKER has no promise of any value and gives no right to any revenue.

The full words: the Terms (use at your own risk, no advice, no custody, what is not allowed, moderation) and Privacy (what Tinker keeps, for how long, and how to delete it).

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