Microsoft 365 Copilot agent types compared (declarative, Studio, Toolkit, and SDK)
A practical map of Microsoft 365 Copilot agent types, how you deploy them (including across customer tenants if you are an MSP), and when to pick each one, as of August 2026. Spoiler from my own delivery work: Copilot Studio declarative agents (agents for Microsoft 365 Copilot) are the path I enjoy building most for customers. The Studio tool and knowledge surface is wide enough for real work, and you still stay on Copilot’s orchestrator.
Microsoft documents two approaches (declarative vs custom engine). Everything else is a builder, runtime, or legacy name. Confusing those three is why “classic agent,” “Copilot Studio declarative,” and “Agents Toolkit” feel like four different products fighting in a trench coat.
