The AI coding tool landscape in 2026 is mature enough to have clear categories. The right tool depends on how you work — inline completions, terminal conversations, or full IDE replacement. Here's the breakdown.
Quick Answer: Claude Code, Codex CLI, and Gemini CLI are terminal-based AI agents, whereas Cursor and Windsurf are full IDEs, and GitHub Copilot is an editor extension. Most support SKILL.md for customization.
Terminal-based agents
Claude Code
Anthropic's command-line coding agent. Runs in your terminal, reads your entire project, and handles complex multi-file tasks through conversation. Supports customization via SKILL.md skills — structured instruction files that teach it your team's specific patterns.
Best for: Complex refactoring, multi-file features, code review, project-wide changes.
Pricing: Included with Claude Pro ($20/month) or Max ($100/month).
Customization: Full SKILL.md support. Skills marketplace at Agensi.
Codex CLI
OpenAI's terminal-based coding agent. Similar concept to Claude Code but runs GPT models. Also supports SKILL.md skills, making it cross-compatible with the same skill files.
Best for: Developers who prefer OpenAI's models or want GPT-specific capabilities.
Pricing: API-based, pay per token.
Gemini CLI
Google's entry into terminal-based coding agents. Supports SKILL.md skills. Runs Gemini models.
Best for: Developers in the Google ecosystem or who prefer Gemini's reasoning style.
Pricing: API-based with free tier.
Editor-integrated tools
Cursor
A full IDE forked from VS Code with AI built into every interaction. Inline completions, chat panel, and code generation. Supports both its own .cursorrules format and SKILL.md skills.
Best for: Developers who want an all-in-one AI IDE and don't mind switching from VS Code.
Pricing: Free tier, Pro $20/month, Business $40/month.
GitHub Copilot
The original AI coding assistant. Inline autocomplete inside VS Code, JetBrains, and Neovim. Excellent at line-level suggestions and small function generation.
Best for: Fast inline completions while you type. Boilerplate generation.
Pricing: Free tier, Individual $10/month, Business $19/month.
Windsurf (Codeium)
AI-powered editor with "Flows" — multi-step AI actions that chain together. Good at understanding your codebase context.
Best for: Developers who want guided multi-step AI workflows integrated into their editor.
How to choose
If you want to keep your existing editor: Use Claude Code or Codex CLI in the terminal alongside VS Code/Neovim/JetBrains. Add Copilot for inline completions.
If you want an all-in-one solution: Use Cursor. It replaces your editor entirely.
If you want customization: Claude Code and Codex CLI support SKILL.md skills. This is the biggest differentiator for teams that want AI to follow specific conventions.
If you want the cheapest option: GitHub Copilot Individual at $10/month for inline completions. Claude Code at $20/month for project-level assistance.
The skill advantage
Most AI coding tools are general-purpose. They write decent code for any project but don't know your team's patterns. SKILL.md skills change this — they teach the agent your testing framework, code review standards, API conventions, and deployment patterns.
Claude Code, Codex CLI, Cursor, and Gemini CLI all support SKILL.md. Skills are portable across these tools — write once, use everywhere.
Browse skills for all compatible agents at Agensi.
Comparison table
| Tool | Type | Customization | Pricing |
|---|---|---|---|
| Claude Code | Terminal agent | SKILL.md | $20/month |
| Codex CLI | Terminal agent | SKILL.md | Pay per token |
| Gemini CLI | Terminal agent | SKILL.md | Free tier + API |
| Cursor | Full IDE | .cursorrules + SKILL.md | Free-$40/month |
| GitHub Copilot | Editor extension | Limited | $10-19/month |
| Windsurf | Full IDE | Limited | Free-$15/month |
Add skills to your AI coding setup at Agensi.