IntroductionX402 introduced a simple idea: let agents pay for API access using the native semantics of the web, HTTP 402. No accounts, no custodians, no browser redirects. Just a request, a payment prompt, and a retry with a signed authorization. But X402 originally operated on a single chain and token, which restricted how widely agents could function. AnySpend removes those limits. It keeps the familiar X402 flow exactly as it is, while adding the ability to pay with any token on any chain....