Based on a light novel series of the same name, this anime tells the story depicted in the first nine volumes of the light novels. Spellcasting in the modern day, familiars, and mass-produced magic devices. Thematically, the story is about lies: the lies we tell others and the lies we tell ourselves.
It's trope-heavy but not to the point of annoyance. It's heavy on intrigue, twists, subversion, and double agents. There's also plenty of head-scratching in store. Some plot elements just aren't explained in depth or at all. Thankfully the show was almost entirely devoid of fan service; it really would have been out of place.
Tokyo Ravens is chock full of characters spanning numerous archetypes: everything from the sadistic goth-loli to the fan-wielding strategist. There are no forced romances, but it reaches for harem anime status without making it quite that far. Plenty of badassery all around if you're looking for it.
Visually, it's pretty solid, but there were many scenes that involved CG that was too different from its backdrop. There are a number of mechanical objects that should have been cel-shaded. Character designs were pretty good; all of the characters were visually distinct. Old men looked like old men and every girl in school didn't look the same.
The ending was pretty satisfying in several ways, but also left several questions unanswered.
Tokyo Ravens has lots going for it, but falls under the weight of its mismatched visual effects, confusing in-universe rules, and predictable characters. That being said, it's still a fun watch.