Coding agent
A coding agent is an AI system that carries out programming tasks end to end: reading a codebase, editing multiple files, running commands, and reacting to the output. It differs from a code assistant in that it decides its own sequence of steps rather than responding to one request at a time.
Every coding agent has the same three capabilities underneath: it can read your files, it can write to them, and it can run something and see what happened. The third is what separates an agent from a chat window — without execution it can only guess whether its change worked.
Agents vary mostly in how much they attempt before checking in with you, and how visible their work is while it happens. That is a product decision, not a model capability, and it is what distinguishes the tools more than the underlying model does.
What this means in practice
Claude Code is the most autonomous of the ones we cover; Cursor's Agent mode does similar work with per-file diff review; Copilot's agent takes on the least per request. Prompt accordingly — the more autonomous the agent, the more your prompt needs explicit boundaries rather than explicit steps.
Prompts for the tools this applies to
Related terms
- Agentic coding
Agentic coding is using an AI tool that plans and executes a whole task in your codebase rather than completing one line at a time.
- Agent loop
The agent loop is the repeating cycle an AI agent runs: decide what to do next, take an action such as reading a file or running a command, observe the result, and repeat.
- Autonomous coding agent
An autonomous coding agent completes a described task without step-by-step supervision: it plans, edits, runs, and verifies on its own, reporting back when done.
- Terminal AI agent
A terminal AI agent runs in your shell rather than inside an editor.