Mastering Context: How to Feed Your AI Agent the Right Files
The #1 reason AI fails is missing context. Learn the art of selecting the perfect file mix for your Cursor or Windsurf sessions.
Mastering Context: How to Feed Your AI Agent
You prompt: "Fix the login bug." The AI says: "I don't see a login file." You sigh.
The difference between a "Junior" AI result and a "Senior" AI result is almost always Context.
AI models like Claude and GPT-4 have massive context windows (200k+ tokens), but filling them with garbage leads to garbage results. Here is how to curate context like a pro.
The "Onion" Strategy of Context
Think of your codebase as an onion. When asking for a change, you need layers.
Layer 1: The Target (Must Have)
The file you strictly want to edit.
- e.g.
src/auth/LoginComponent.tsx
Layer 2: The Direct Dependencies (Should Have)
The data structures and utilities the target uses.
- e.g.
src/types/auth.ts(Interfaces) - e.g.
src/utils/api-client.ts(How you fetch data)
Without Layer 2, the AI hallucinates types and functions that don't exist.
Layer 3: The Patterns (Nice to Have)
A similar file that is already working correctly.
- e.g.
src/auth/RegisterComponent.tsx
This is the secret weapon. By showing the AI a "correct" example from your own codebase, it instantly mimics your style, naming conventions, and error handling patterns.
Managing Context in Cursor
Cursor makes this easy with @symbols.
- Don't just add folders. Adding
@srcis lazy and fills the context with noise. - Use
@Codebasesparingly. It searches reasonably well, but manually adding the 3-4 exact files is always 10x better. - The .cursorrules file. This is your "Permanent Context". Put your global rules here (stack, style guide) so you don't have to repeat them.
The "Context Dump" Technique
Before starting a big refactor, create a temporary file called CONTEXT.md.
Paste relevant snippets, database schemas, and business logic requirements into it.
Add @CONTEXT.md to your chat.
This gives the AI a "brain" to refer to that is cleaner than reading 50 raw code files.
Summary
- Be surgical: Add specific files, not whole folders.
- Show examples: Always provide a "reference" file.
- Use .cursorrules: For improved baseline performance.
Better input = Better output.