Tooling
Before you compare products, compare types. AI coding tools come in three main shapes, and each one fits a different kind of work. Pick the wrong shape and a great tool can still feel useless on your team. Here is how the three compare, from someone independent of every vendor.
The AI coding market looks like a long list of rival products. Underneath, there are really only three shapes. Each one sits in a different place in your workflow and handles a different size of task. Get the shape right and the exact product is just a detail. Get it wrong and no amount of model quality will save it.
An inline assistant works at your cursor. As you type, it guesses the next line or block and offers it for you to accept. The unit of work is the line. It keeps you in flow and is the easiest to adopt, because it never takes over: you are still the one writing, just faster. The line is also its limit. It will not plan a change, edit five files, or run your tests. Think of it as autocomplete with a much bigger brain.
An IDE agent runs the full agent loop (plan, edit, run, check), but inside your editor, with the code in front of you. The unit of work moves up to the file or the whole feature. You get the agent's multi-step power plus the editor's fast review: you watch each change land, accept it or steer it, and stay in the view you already trust. It fits developers who want a real agent without leaving the place where they read and edit code.
A CLI agent runs in the terminal and treats the whole change as one unit of work. It reads the codebase, plans, edits many files, runs commands, and handles long tasks. Because it lives on the command line, you can script it, combine it with other tools, and run several at once. The trade-off is that you are further from the visual diff and you work through text. It fits people who think in workflows and are comfortable directing an agent instead of editing by hand.
Do not ask which shape is best. Ask which one fits the work in front of you, because most strong teams use more than one. The questions that decide it:
An inline assistant suggests the next line while you type, and stops there. An agent, whether in your IDE or the terminal, takes a goal and works through several steps and files to reach it, checking its own results. The assistant helps you write. The agent takes charge of a result.
Cursor is the clearest example of an IDE agent: a full editor with an agent loop built in, plus inline suggestions. Many products now cover more than one shape, which is exactly why it helps to compare shapes first and products second.
Usually not just one. A common setup is a CLI agent for big multi-file changes and an inline assistant for quick edits, with IDE agents for those who prefer the editor. Agree on the practice and the review bar first; let the shape follow the work.
Tooling
An independent, hype-free comparison of the three main AI coding tools by what they are actually good at, from someone with no vendor to favor, so you can match the tool to how your team works.
Foundations
An AI coding agent is more than autocomplete and less than a senior engineer. This guide gives a clear definition, explains the loop that makes it an agent, and shows what it is not.
The shape matters more than the brand, and the practice around it matters more than both. If you want help choosing across these types and building the workflow that makes them pay off, that is exactly what I do in workshops and advisory. Let's talk.