A non too technical, simplified but slightly funnier explanation.

Coordinates agents, skills, and tools into repeatable workflows. Manages routing, state, inputs/outputs, validations, QA loops and execution to deliver complex outcomes.
A reusable capability that packages domain instructions, tools, and logic for a specific job. Helps agents perform common tasks consistently.
A standard connection layer that links AI systems to external apps, data, and environments through a common interface.
A callable function, API, or script the system can use to fetch data or take action.
A goal-directed software worker that uses memory, context, and tools to plan and complete multi-step tasks.
The core model that interprets instructions, reasons over context, and generates text, code, or decisions.