Karakol is a genuinely easy place to travel solo — it's a small, walkable town with a real backpacker and adventure-travel presence, so you won't be the only visitor figuring things out on your own.
General safety follows normal travel-sense rules: it's a low-crime town by most standards, but use the usual caution after dark and with belongings, as you would anywhere. For tours specifically, going solo is often better on a group-rate tour rather than a private one — you'll usually end up riding or trekking alongside other travelers, which a lot of solo visitors end up preferring anyway.
If you're nervous about arriving with no plan at all, the city tour on your first day is a low-key way to get oriented before committing to anything more adventurous.
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