Someone would look at our process and say "that's not agile!" and they might be correct, technically speaking. I don't personally care what it's called as long as it works.

We agree to requirements up front with our customer; we might change stuff as we go along if our customer realizes that what they asked for won't work (this happens occasionally), which is fine, but otherwise we don't let them change stuff around on a whim, and we don't allow scope creep. If they want a new feature, that's version 2 (or 3, or 4).

We don't meet very frequently. We do check in to make sure we're on target, and deliver features incrementally when it makes sense to do so. We do sprints. We talk about when things are working and when they aren't, but only when we think it's a good time to do so.

At the end of the day, you need to tailor the process to your needs and what makes sense to you and your team.