Harking to mind the classic episode "A Piece of the Action" insofar as concerns over the effects of contaminating a culture by leaving something behind on a visit to a developing world.
In this instance, the pollutant in question is in the title, naturally.
In a lot of ways, this is another Malcolm Reed episode. Reed, along with Phlox, probably received the most attention outside of the Big Three (Archer, T'Pol, Trip) during the second season. In this one, he's once again fretting over something. It seems when he isn't concentrated on improving ship's weapons, Reed is always fretting over something. Call it a character hallmark. You can certainly watch "The Communicator" to enjoy Reed fretting (it's very similar to the fretting in "Minefield," though less existential).
It may be better to watch the episode for how it helps the season to continue tracking the more unexpected developments of deep(ish) space exploration, things our crew didn't anticipate during its first year (though there were plenty of complications then, too). What the second season did best was explore the finer details, and the crew's reactions to them.
In this instance, it's about accidentally leaving a valuable piece of technology behind. Reed frets, of course, and Archer calculates. He calculates a lot of thoughts throughout the season. The most (in)famous example is "A Night in Sickbay," in which he weighs the value of diplomatic tact. In "The Communicator" he decides what cultural contamination is worth versus the lies he's willing to tell. It's the first but not the last time this season he does this (another notable example would be "Canamar"). This is unique territory. In Voyager Janeway was mindful of upholding Starfleet protocols. In Enterprise those protocols don't exist, and Starfleet neither doesn't, either. It's pretty similar to Kirk's famous bluffs (corbomite, anyone?), but ably demonstrates Archer's increasing ability to think on his feet. Earlier in the series, he was more prone to self-doubt, perhaps something Vulcans saw in all of humanity at the time.
This one was designed to make most of these points, and it hit them pretty well.
And so yeah, you can see this as an Archer episode just as easily as a Reed episode. I'll let you decide how much importance you want to place on such details. Basically an entertaining and useful episode for the series and enjoyable for veteran fans.
franchise * series * essential * character
Memory Alpha summary.