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AI Digital Twin
Ask about Frits' work, by typing or with your voice: an AI version of his CV that answers only from what he wrote himself.
TRY ABOVE ↑Listed in the LangChain docs ↗·Safety checks for agents that pay →·New: what 50,000 paid x402 endpoints show →
SAFE PAYMENTS FOR AI AGENTS
FIZZL
AI agents now pay for things on their own. Fizzl checks every payment before your agent signs it and every paid answer after it, and runs four live services that agents find and pay per call.
4Live services, paid per call
50K+x402 endpoints checked daily
5Payment networks
0Accounts or API keys needed
LIVE · PAID PER CALL BY AI AGENTS
Tools for AI agents.
Four small services I built and run. AI agents pay them per use with digital dollars (USDC), without an account or API key, through x402: an open standard that lets software pay software. Try each one live below: the demos are free.
4live services
$0.001smallest call
148coins scanned
Base + Solanapaid in USDC
01Agent asks
02Service answers 402 + price
03Agent pays in USDC
04Answer, in the same request
WALLET SAFETY · FROM $0.01
Check it before your agent signs.
A green, orange or red verdict before an agent or wallet signs a transaction, a token approval or a signature, or buys a token. Paid answers come with the reasons and a signed receipt.
OPEN PRESIGN-GUARD ↗
TOKEN CHECK● LIVE
Pick a token.
DEVELOPER TOOL · FREE CHECK
Why is my x402 endpoint broken?
Checks a paid API the way a paying agent would: the 402 challenge, networks, price, payout wallet and discovery, with a fix for every problem, also as a free GitHub Action on every push. Agents also pay $0.001 to ask "is this safe to pay?" before paying an unknown endpoint.
OPEN X402 DOCTOR ↗ GITHUB ACTION: CHECK ON EVERY PUSH ↗
ENDPOINT CHECK● LIVE
TRADING SIGNALS · FROM $0.01
Is a coin bullish or bearish right now?
Ichimoku Cloud signals, price levels and a ranked scan of 148 coins, for trading agents and for people. The daily trend is free; the full signal, levels and today's top 10 setups are paid per call.
OPEN ICHIMOKU SIGNAL ↗
WALLET APPROVALS · 3 FREE CHECKS A DAY
What did I actually approve?
Temporarily offline from 16 October until 1 November.
Checks a wallet's approvals, or an approval you paste, with presign-guard and explains the verdict in plain language: who can move what, for how long, and whether to revoke it. 3 free checks a day on the site, no wallet needed. Try one of the sample approvals.
OPEN PLAINTEXT ↗
APPROVAL IN PLAIN LANGUAGE● LIVE AI
RESEARCH AND GUIDES
- We check 50,000 paid x402 endpoints every day: what works, what breaks, and what happened when we paid random ones.
- x402 on Stellar: 631 paid endpoints, and the asset-field mistake that blocks 7% of them.
- The seven most common x402 seller mistakes, each with the fix as code.
- Tools to check an x402 endpoint before an AI agent pays, compared: seven checkers, by the question each one answers.
- Approve AI agent payments in your own wallet with AC2: above its limit, the agent pays only with your signed approval.
WHO BUILDS IT
Built by
Frits.
I build Fizzl with Claude and Claude Code, after years in customer success: listen first, then fix the real problem. Every tool does one thing well and explains what it found; the model explains, but never decides on its own.
PROJECTS
What I build.
01 / LIVE AI DEMO
Talk to the Digital Twin.
FIZZL DIGITAL TWIN
● LIVE
02 / AI CUSTOMER SERVICE AUTOMATION
ReplyDesk
An interactive demo based on my GitHub project: an AI workflow for customer service that turns an incoming customer message into a professional draft response.
OPEN LIVE DEMO ↗ SOURCE CODE ON GITHUB ↗AI SUPPORT ASSISTANT● LIVE AI
AI CONCEPT
Click “GENERATE DRAFT” to generate an example response.
CHECK BEFORE SENDING
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FIZZL Project Portfolio
A collection of AI, automation and digital projects and experiments.
VIEW PROJECT →03 / LIVE AI DEMO
AI Process Agent.
An AI workflow that analyzes a customer request, checks relevant information and determines which action can safely be prepared — with human oversight for critical decisions.
FIZZL AI PROCESS AGENT● LIVE DEMO
The AI is analysing the case…
RISK—
CONFIDENCE—
HUMAN OVERSIGHT—
Technical details
LET'S CONNECT
Build something
together?
A question about Fizzl, a pilot for your API, or something to build together? I read every message.