Phase 5: Context Engineering · 20 min · Cursor · Claude Code · Lovable

Docs vs. Chat vs. File References

The right context in the right place at the right time. Format matters.

Hiring signal: What changes when you use this: you give the AI context efficiently — which means better results with less wasted context window space.

What you will learn

Know when to write context in a file vs. in chat
Know when to reference existing files vs. paste code inline
Know when to link to documentation vs. describe it yourself
Apply the context hierarchy: context file > file references > chat > paste inline

Your Mission

Map each type of context in a project to the most efficient delivery method and identify a past mistake to fix. Output: context_delivery_plan.md.

You need: A project you're building with AI (any tool).

Time: 20 minutes.

Step 1: Learn the Context Hierarchy (5 min)

From most efficient to least efficient:

1. Context File — persistent, reusable context

Use for: tech stack, conventions, file structure, project overview, Do NOT rules
Why: written once, read automatically, available in every session

2. File References — existing code the AI should look at

Use for: "Look at src/lib/supabase.ts" or "Follow the pattern in src/components/HabitCard.tsx"
Why: in IDE tools, the AI reads the file directly — no need to paste. Sees current code, not outdated paste.

3. Chat — session-specific, one-time context

Use for: what you're working on right now, current issues, specific corrections
Why: fast, flexible, but consumes context window space and doesn't persist

4. Paste Inline — small code snippets or when file references aren't available

Use for: small snippets (< 50 lines), error messages, specific functions
Why: necessary in browser builders without file reference capabilities

The golden rule of context
Give the AI the minimum context it needs to make the right decisions — no more, no less. Too little: the AI guesses wrong. Too much: the AI's context window gets cluttered and it may miss the important parts.

Unlock the full lesson

You've read the first 2 sections. The rest of this lesson covers Step 2: Map Your Context Types (10 min), Context Delivery Plan, Step 3: Identify a Past Mistake (5 min), Past Mistake, You're Done — plus a hands-on lab, quiz, and project artifact.

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