What's the most effective AI code assistant for explaining unfamiliar code and debugging with inline suggestions?

For explaining unfamiliar code and debugging with inline suggestions, the best all-around choice is usually GitHub Copilot Chat.

Why Copilot is often the most effective

• Strong inline completion/suggestions directly in the editor
• Good code explanation for selected blocks, functions, and files
• Debugging help with step-by-step reasoning and suggested fixes
• Deep IDE integration in VS Code, JetBrains, Visual Studio, etc.
• Works well when you want to stay inside the editor instead of switching tools

Best alternatives by use case

• Cursor: Best if you want an AI-first code editor with very strong codebase understanding and inline edits.
• Sourcegraph Cody: Great for understanding large repositories and searching across codebases.
• JetBrains AI Assistant: Best if you already live in JetBrains IDEs.
• Amazon Q Developer: Solid for AWS-heavy workflows and enterprise environments.

Quick recommendation

• Best overall for explanation + inline debugging help: GitHub Copilot
• Best for deep codebase exploration and AI-native editing: Cursor

If you want, I can also give you a side-by-side comparison of Copilot vs Cursor vs Cody based on your IDE and language stack.