What is an AI coding agent?
Updated Oct 26, 2026 · Sources listed at the end
An AI coding agent is software that takes a programming task in plain language and carries it out in multiple steps, using tools such as file editing, a terminal and your Git host, rather than only suggesting code for you to paste.
The three common forms
- CLI agents run in your terminal on your machine, for example Claude Code, which Anthropic describes as reading your codebase, editing files and running commands.1 See CLI coding agents.
- IDE agents run inside an editor such as VS Code or JetBrains. Cursor’s documentation calls Cursor “a coding agent for building ambitious software”.2 See IDE agent extensions.
- Cloud or background agents run on remote machines and usually return a pull request. See background coding agents.
How agents get context and tools
Agents read project instruction files such as AGENTS.md, which describes itself as “a README for agents”.3 They connect to external systems through the Model Context Protocol, an open standard for connecting AI applications to tools and data.4
How to compare agents
Price, free tier and supported editors differ a lot. Our AI coding agents list shows each one’s free plan and starting price from vendor pages, and links the vendor page we used.
Footnotes
Tools mentioned
- Claude Code: paid from $20/mo
- OpenAI Codex: free plan, paid from $8/mo
- Cursor: free plan, paid from $8/mo
- Devin: free plan, paid from $20/mo
- Jules: free plan, paid from Free
- Cline: free plan, paid from Free