By late August 2026 the large exchanges are no longer arguing about whether models should see a market. They are shipping different answers to a narrower question: may the model press the button, and what can it reach when it does. Here is the comparison in prose, not a scoreboard.
Binance Agent OS, launched 20 August 2026, is built for autonomy inside a fence. Compatible agents — ChatGPT, Claude, Codex, Cursor — can read markets and place supported trades. Each agent is assigned a subaccount. Withdrawals are blocked by default. The user funds that box; that balance is the practical loss limit. The user can require approval per order, or allow the agent to fire once permissions are set. The posture is: isolate, then optionally let go.
Coinbase for Agents is the payments-native cousin. The distinctive rail is x402: HTTP 402 plus stablecoin settlement, built with Cloudflare in the wider foundation. ChatGPT and Claude show up as the client side of that stack, alongside wallets and spend controls. Trading and portfolio tools exist, but the design center is machine checkout — an agent that can pay for a call, not only place a futures order. The posture is: teach the web to charge software.
Kraken’s in-app assistant is propose-and-approve. It can draft a plan, point at idle cash, or prepare a buy, sell or convert. It does not execute until the user taps yes. Kraken’s help text is explicit: nothing moves without that confirmation. There is a separate developer MCP path for people who want more automation, but the consumer default is a recommendation, not a live agent on the book. The posture is: advise, wait.
Read across the row. Isolation: Binance makes the subaccount the product; Coinbase pushes dedicated wallets and limits on the payment rail; Kraken keeps funds in the user’s normal account because the model cannot move them alone. Autonomy: Binance can be set to fire; Coinbase’s agent tools can pay and act inside caps; Kraken will not. Client surface: Binance lists ChatGPT, Claude, Codex and Cursor; Coinbase leans ChatGPT/Claude plus x402; Kraken is first an in-app copilot.
None of these rails removes prompt injection, a confused model, or a user who funds the box too generously. They only change where the blast stops. Pick the posture that matches the job — autonomous box, machine checkout, or human-confirmed advice — and size the funds as if the model will do the worst allowed thing once.
