The beginning episode of Matantei Loki Ragnarok is a little rough around the edges. It doesn't explain exactly what's happening with the characters; it's a bit vague about Loki being a god and having magic powers and being exiled, and about where exactly this storyline is going. It has cheezy moments where they dramatize everything and forms of animation that occur only in this first episode (aka, the grainy pics, which I thought were cool.)
But what can you expect in the first episode? They are toying with what works and what doesn't for the series. Granted, the starter isn't where you want to do that, but it is at least an attempt.
In this first episode, gain the 3 main characters that are needed; Mayura, Loki, and Yamino. it sets a base for characters to grow out from, which comes in handy later in the series. It also characterizes Mayura well and gives Loki the strange behavior that is not-quite-childlike. Viewers can sense that there's more than meets the eye about this pint sized detective even before the halfway point in the episode.
It was fairly good for a beginning show, and even though it is rough around the edges, it has some great promise.