This sits in an interesting sweet spot. MCP is overkill for most "just compose a URL" use cases, and OpenAPI is designed for machines talking to machines, not agents reasoning about user intent.

The XML-at-a-well-known-path approach reminds me of robots.txt or llms.txt — discoverability via convention rather than registration. That's a good instinct for adoption.

Question: have you thought about how this interacts with existing deep linking / universal link schemes on mobile? iOS and Android already have intent systems that do something similar. If AUI could bridge to those, you'd get native app support almost for free.

MCP configs owned by users is the right trust model. Agent gets capabilities without platform handling secrets. Scales cleanly.

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