Is this an alternative to "I think, therefore I am"?
You exist because you have a location ("here")?
This would still seem to require qualitative events and cognitive activity as more fundamental for the conclusion. Since objects devoid of memory-dependent processes and experiences have neither presentation nor understanding of themselves as being anywhere and being anything.
However, if you deem your own self-validation to be insufficient -- if you are trying to verify your "I am"-ness via another party, requesting assistance from other appearances that are likewise conscious (or at least act like they are), then I can limitedly assist you in this endeavor.
Your entreaties are indeed manifesting "here" (a spatiotemporal location, at least as represented by a "mind"). I can reciprocally attest that your text product has "be-ing" as both visual and (optional) auditory phenomena. Beyond that I will not venture whether their supposed distant "cause" is a biological organism or the programming of a machine.
You may also solicit opinion from members of the aforementioned "absent to itself" manner of be-ing... like a rock or the Moon. However, I wouldn't be hopeful of response. Even when rendered second-hand "visible" by psychological affairs, that normally "invisible" mode of existence remains quite snobbish.