Giving AI the Full Picture

8.1: AI Thinks Vertically, You Think Horizontally

This is the mental model that explains most AI failures:

AI can only go vertical -- straight down from your prompt to implementation. It builds top-to-bottom, one thing at a time, powerfully.

You control the horizontal -- the landscape of your system. Existing patterns, constraints, integrations, history, future plans.

                              YOU
                               |
    Patterns ---- History ---- | ---- Constraints ---- Future
                               |
                               |  AI goes straight down
                               v  from wherever you place it

When AI builds the wrong thing, the question isn't "why is AI broken?" It's "what horizontal context did I miss?"

8.2: Without vs. With Context

Without your context:

Prompt: "Add login"

AI implements a generic login form.
Wrong patterns. Wrong auth provider.
Doesn't integrate with your system.

With your context:

Prompt: "Add login. We use JWT with refresh tokens.
Integrate with our SSO provider via AuthService.ts.
Rate limit to 5 attempts/minute. Log to audit service.
Follow the pattern in src/pages/signup.tsx."

AI implements login that fits your system perfectly.

The difference is entirely in the horizontal context you provided.

8.3: The Horizontal Checklist

Before every significant prompt, run through this list:

You don't need all seven for every prompt. But for anything substantial, check at least integrations, patterns, and constraints.

8.4: The Context Window is Precious

AI can only "see" a limited amount at once. Use it wisely:

8.5: When to Start a New Chat

A fresh context often works better than trying to fix a polluted one. Start new when:

• After shipping a feature -- clean slate for next task
• AI keeps repeating the same mistake -- it's stuck in a loop
• You switched to unrelated work -- old context will confuse
• Responses get confused or repetitive -- context window is full

When starting fresh, bring context efficiently:

"Read user rules. Read @src/services/AuthService.ts.

In our last session, we decided:
1. JWT for auth (not sessions)
2. Refresh tokens in httpOnly cookies
3. 15 min access token expiry

Now implement token refresh."

8.6: Signs of Context Problems

8.7: The Brainlift Connection

Your Brainlift from Module 2 is horizontal context -- specifically, the context that AI cannot possibly have on its own. Always include it when starting a new feature. It's the difference between generic AI output and code that actually fits your project.