Minor spellcasters who weave arcane magic into the practice of their trade, Magewrights are an NPC class for Dungeons & Dragons 3rd Edition that appeared with the Eberron campaign setting. Sort of an arcane version and the Adept, the Magewright is the NPC version of the Artificer; a minor mageling who studies basic spells until they can cast them through rote repetition, or who has an instinctive knack for casting spells that are of use to aid or enhance their daily labors, predominantly in the fields of making stuff. Essentially, if the Artificer is the guy who crafts vorpal swords and world-shaking artifacts, then the magewright is the guy who produces utilitarian magitek. The limits of their spell list means they can't actually meet the requirements to craft almost anything magical and useful to most adventurers. Among these few items are raw pluses on weapons and armor, slick armor, Stone of Alarm, and a Helm of Comprehend Languages and Read Magic. Magewrights have an unusual casting system: They prepare spells like Wizards but only know a small number of spells equal to their intelligence modifier, plus a cantrip, and gain another int mod number of spells, plus another cantrip, at every level that's a multiple of four. This means they'll only know two or three spells a level.
Like fellow NPC caster Adept, Magewrights are actually better than several non-casting core classes. Unlike the Adept they don't have spells that are in anyway useful in a fight except Animate Rope and Grease till level 8, 12th if explosive runes+dispel doesn't work, so they aren't quite as good.
Magewright was not in the original Tier System list and it's contested on if it's a low Tier 4 or high Tier 5. It's able to contribute well to a good number of situations, but has very obvious flaws in coverage and lacks the sheer power of a proper caster. Compared to Adept their spell list is nowhere near as good, and while Adept can prepare any spell from his list he want, Magewrights have a limited number of spells known. Various other methods of expanding their poor spell list, such as Runestaffs and the Raiment of the Four (Magic Item Compendium), can greatly improve them. One serious point in their favor is that they are arcane casters in Eberron, which means they can use Eternal Wands of any arcane spell without difficulty, greatly expanding their spell options.