Live tools that AI agents find and pay for per call, and AI workflows built around practical business problems.
Small tools I built and run for AI agents. Agents find them on their own and pay per use with digital dollars, without an account or API key, through x402: an open standard that lets software pay software. People can try them for free on the web.
Reads a transaction, approval or signature before it is signed and says in plain words what it can move and to whom: green, orange or red. Also token verdicts (honeypots, mint and freeze powers, permissioned tokens) and wallet approval audits.
OPEN PRESIGN-GUARD.FIZZL.EU ↗Spending limits and phone approvals for AI agents. The agent keeps its own key, and every purchase gets a readable receipt. Sign in with a wallet, Xaman, Pera or e-mail, and connect it to ChatGPT, Claude or Grok.
OPEN WALLET.FIZZL.EU ↗Checks x402 paid APIs before an agent pays and before a seller ships: a quick go / caution / no-go preflight, batch and deep checks, a full diagnosis with a fix hint per check, and the fix code itself. Scans every endpoint in the Coinbase Bazaar daily.
OPEN X402-DOCTOR.FIZZL.EU ↗Buys the right paid API for an AI agent in one call: the agent says what it needs ("weather in Amsterdam tomorrow", "BTC price"), Fizzl picks the x402 service x402 Doctor has seen paying out day after day at a fair price, fills in its input, pays it (up to $0.01) and returns the answer, checked by TypeSafe Jev. $0.02 a purchase; nothing is charged when no seller delivers.
OPEN BUY.FIZZL.EU ↗Ichimoku Cloud signals for AI agents across hundreds of crypto pairs: a per-pair signal with entry, stop and targets, multi-timeframe confluence, key levels, a market scan and ranked setups. With a public paper-trading track record.
OPEN ICHIMOKU-SIGNAL.FIZZL.EU ↗On OKX's TapeOut, one transfer can hand over a circuit with its container, its on-chain site and its name, while a wallet shows an ordinary NFT transfer. presign-guard checks the transaction on X Layer before an AI agent signs, paid per check in USD₮0. Next to it: a fully on-chain directory of every x402 endpoint on X Layer, with today's verdict. Built for OKX's TapeOut Accelerate hackathon.
OPEN THE ON-CHAIN DIRECTORY ↗ OPEN PRESIGN-GUARD.FIZZL.EU ↗ VIEW THE CHECK ON GITHUB ↗ WATCH ON YOUTUBE ↗A shop's AI support agent refunds customers through PayPal's Agent Toolkit. The guard checks every refund against PayPal's own data: only the customer who wrote, never more than is left, within the shop's limits, and the owner's Approve or Deny above them. Watch it answer five emails live on the PayPal sandbox, two of them scams. Built for the PayPal AI Hackathon.
OPEN LIVE DEMO ↗ WATCH THE 3-MINUTE VIDEO ↗ VIEW PROJECT ON GITHUB ↗An open benchmark of whether AI agents pay safely: 14 scenarios with honest sellers and traps, run offline, with nothing really paid. It found two gaps in my own agent guidance; after the fixes the agent avoided 27 of 27 traps, against 15 of 27 without it.
VIEW RESULTS ON FIZZL.EU ↗ VIEW PROJECT ON GITHUB ↗AI analyses a customer case and proposes actions; fixed rules decide what runs, what needs approval and what stays blocked until a person says yes.
OPEN LIVE DEMO ↗ VIEW PROJECT ON GITHUB ↗ The first open can take up to a minute: the free hosting wakes the demo up first.An AI-assisted customer-service workflow that turns an incoming customer message into a structured, editable draft response using context and business knowledge.
OPEN LIVE DEMO ↗ VIEW PROJECT ON GITHUB ↗ The first open can take up to a minute: the free hosting wakes the demo up first.Ask about Frits' work in English or Dutch: an AI version of his CV that answers only from what is on it, and says which part it used.
OPEN LIVE DEMO ↗ VIEW PROJECT ON GITHUB ↗ The first open can take up to a minute: the free hosting wakes the demo up first.