Item from The Gods are Bastards by D.D. Webb
An ancient sentient sword — a weapon with vast knowledge, a cutting personality, and opinions about everything its wielder does wrong, which is apparently everything.
Ariel is not just a sword — she's a person who happens to be sword-shaped. She's opinionated, acerbic, and possessed of an encyclopedic knowledge base accumulated over centuries of existence. She comments on Gabriel's decisions with the withering precision of a disappointed professor, which is appropriate given that she ended up at a university. As a weapon, she's formidable — an artifact-grade blade with magical properties that scale with the skill and power of her wielder. As a companion, she's exhausting — she never shuts up, she's always right, and she has zero interest in Gabriel's feelings about either of these facts. Her origin is mysterious and tied to ancient history that predates the current age. She contains knowledge that even Tellwyrn would find valuable, which she dispenses reluctantly and with editorial commentary.
An elegant longsword of clearly ancient manufacture, the blade etched with script in a language that predates modern Tiraan. The metal has a faint luminescence that intensifies during magical activity. The hilt is wrapped in material that never degrades. It looks like a museum piece that could still kill you, which is accurate.
Also known as: Ariel, The Talking Sword