These hooks are exposed by authcache_debug, one of them is implemented by authcache itself, but are missing from the authcache.api.php file.
Thanks for reporting. I'm not really happy with the API around the debug module. Currently debug-info is stored alongside with the rendered page into the cache_page bin. I initially thought that this was a pretty neat hack, but now as I'm trying to add non-core cache backends (like boost or external cache) it starts to fire back. So chances are that these hooks will go away. Therefore I currently cannot recommend using them.
Fixed in 8dcaa36
Automatically closed -- issue fixed for 2 weeks with no activity.
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