This provides some documentation for initial WebMCP features in the upcoming v22 release.

Some decisions made in the process which reviewers are welcome to contest:

• I put this under the "Build with AI" header, which makes it visible without an expando. That honestly might be too much visibility given how experimental this all is, but there's no other category to put it under, so I think that's the best we can do now.
• I tried to give a little bit of context about the intended use case without going into many specifics (ex. you need to sign up to get access to Chrome's documentation) or distracting from the overall doc. Ultimately this isn't a great explanation of WebMCP as a whole or the broader story around that, but I think that's a higher-level discussion than this particular doc can drive.
• I didn't get into the nuances of the input schema (ex. what types are allowed, what validators/constraints are allowed) as that seemed a bit out of scope for Angular and even I don't know the full scope of the edge cases. Hopefully as the spec matures we'll be able to link to other quality resources about those concepts.
• I didn't expand on the return type both because I don't have a ton of visibility into what is supported and also because I think it goes somewhat out of scope of Angular.
• I suspect some users might get tripped up by the fact that execute is an async function running in an injection context, meaning inject works before an await, but not after it. This is an existing hazard of async functions in injection contexts, so I didn't call it out specifically.