AI coding assistants fall into four types: autocomplete tools that suggest the next lines, chat assistants that answer questions and draft code, agents that carry out multi-step tasks across a project, and app generators that build a small app from a prompt. The best choice depends on who is using it and how much review the output will get.
Tools and features change quickly, so we compare types, not product versions. Always check current capabilities and terms.
The four types
| Type | What it does | Best for | Watch out for |
|---|---|---|---|
| Autocomplete | Suggests lines or functions as you type | Speeding up routine coding | Accepting suggestions without reading them |
| Chat assistant | Answers questions, explains code, drafts snippets | Learning, debugging, small tasks | Copy-pasting code you do not understand |
| Agent | Reads the project, edits files, runs commands and tests | Larger tasks with clear instructions | Large changes that are hard to review |
| App generator | Builds a working small app from a description | Prototypes and demos | Hidden bugs, security, hard to maintain |
How to choose
- Who will use it? Experienced developers get the most from agents. Beginners need chat and explanations.
- What is the task? Boilerplate, debugging, tests, refactoring or a prototype.
- What are the data rules? Check what code and data are sent to the vendor and how they are stored.
- Does it fit your workflow? Editor, version control, review and testing.
- What does it cost? Seats, usage and model limits.
Test before you standardise
Give two or three tools the same real, small task from your codebase. Compare:
- Did it understand the existing code?
- Did the result pass your tests?
- How much review did it need?
- Did it invent functions or libraries that do not exist?
- How easy was it to steer when it went wrong?
Our practice
We use more than one kind of tool, and we use agents only on tasks we can review. Whatever the tool, a developer reads the change, tests run, and nothing is merged on trust. See AI coding do's and don'ts, reviewing AI-written code and how we use Claude.