Using arginfo generating stubs in PECL extensions

Might be better in php-internals (haven't subbed yet), but: I noticed one of the new facilities in PHP 8 was generating arginfo from a PHP stub. This is pretty useful for reasons elaborated elsewhere, but I'm wondering how this should be used for PECL extensions. I noticed what PHP itself does is keep the generated arginfo header. My questions are: 1. Should this be used at all PECL extensions yet? That is, is this some PHP facility that isn't ready for external usage yet? 2. I noticed the build system deletes the stub after it's built the object files. Since I might want to keep the header (for PHP 7.x users), this is a bit annoying, especially as PHP itself keeps them. 3. Are the headers that get generated have any guarantees on usability in PHP 7.x? 4. Part of #2, because it deletes the headers, it makes rebuilding if you generate a change in source *very* annoying, because the header won't be found. 5. Actually downloading PHP-Parser during build is really unexpected. I assume if I have it on my include path it won't do that, but for isolated builds it could be really confusing. I assume if I ship arginfo header in a release tarball, it won't do that? This facility isn't really documented yet, so I'm left wondering.