All tubeless tires are required to have "tubeless" stamped on them.

You can also look at the valve stem,

If its shape slightly tapers from the cap to the rim, and you can see the thickness of your rim at the base of the stem, it is a tubed tire.
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If its shape slightly tapers from the cap and bulges rapidly at the base near the rim, and overlaps the rim and you cannot see the circle at the base, it is tubeless.
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Guess I should get pictures huh?