FEP-844e: Capability discovery has been published to the FEP repository:

https://codeberg.org/fediverse/fep/src/branch/main/fep/844e/fep-844e.md

I already use it to signal RFC-9421 support. An anonymous Application object is added to actors:

{
  "generator": {
    "type": "Application",
    "implements": [
      {
        "name": "RFC-9421: HTTP Message Signatures",
        "href": "https://datatracker.ietf.org/doc/html/rfc9421"
      }
    ]
  }
}

All important information is embedded, so additional HTTP requests are not necessary.

#FEP

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