It's like someone wrote this episode of Futurama with a gun to their head, being forced to involve all the tertiary characters of the show in one giant explosion of Zoidberg hate. Which is my way of saying that this is one hell of a good episode.
At the end of this half hour, you will see why you should seek counseling and high-grade medication the moment you start liking Zoidberg. Spoilers ahead...
If you like Zoidberg, Hermes, and Scruffy, this is the episode of the year for you. Just kidding. There's no way you like Zoidberg. The entire point of the Zoidberg character is to be intensely irritating, while lacking the functional sociopathy that gets the other characters into such wonderful stories. The other characters can be fun. Zoidberg's just a putz.
And Hermes makes it clear he feels exactly that way throughout. Although they crank up the hate Hermes displays for Zoidberg in the first part of the episode, being constantly insulted is such a part of Zoidberg's overall sad-sack persona that it's not jarring. Hermes gets plenty of chances to actively hate Zoidberg because he's conducting performance reviews. He finds that his own performance is lacking, and starts slowly converting himself into a robot. The sequence includes a lot of good sight gags, and a lot of excellent Cylon references.
Zoidberg, pathetically grateful for Hermes' attention, even if it's negative, is distressed by the fact that, the more robotic Hermes gets, the less he goes out of his way to make Zoidberg's life miserable. He's so at a loss that he makes Hermes' extra parts into a literal meat-puppet, and, eventually, saves Hermes from himself. But, of course, Hermes still hates him.
An ever-popular minor character gets quite a lot of cameos in this episode. Good old Scruffy, the janitor, shines in the performance reviews, "My job? Toilets and boilers, boilers and toilets. Plus that one boiling toilet. Fire me if'n you dare." Well said. For those Rule 34 devotees, who have been following Scruffy's ongoing interest in weird porn, his reading material of the episode is Astounding Tales of Doing It and Lady Chatterley's Janitor. Both of which I want to read. Come to think of it, there hasn't been a Futurama spoof book yet that I haven't wanted to read. Someone could make a mint on those.