Strategy screen: plan before you build

Your mission

Get Claude to plan a browser game with you (the one you’ll build in Level 3) before writing any code, push back on the plan until it’s right, and save it to a file.

Why it’s worth it

For small stuff, like “make the button blue”, just ask. But for bigger builds, the most expensive mistake is Claude building the wrong thing well: twenty minutes of solid code for a game that isn’t the one you pictured. Then you’re untangling instead of building.

Pro players check the map before they run. Plan mode is your strategy screen: Claude looks around, thinks it through and shows you a plan, but it can’t change any files until you approve. Fixing a plan takes ten seconds. Fixing a finished build takes ages.

Switching into plan mode

Press Shift+Tab to cycle through the permission modes, and watch the status line at the bottom of the screen. When it shows ⏸ plan mode on, you’re in.

In plan mode, Claude can read files and think, but edits are blocked. When it has a plan, it shows it to you and asks how to proceed. You can:

• Approve it, and choose how Claude carries it out. For example in auto mode, where it builds without stopping to ask about every step, or with accept edits, where file edits happen automatically but it still asks before running commands.
• Keep planning: tell it what to change, and it revises the plan, still without touching any files.

Build it

Your game gets its own folder, next to speedrun-lab (Level 3 continues in it). In your terminal, go to the folder that contains speedrun-lab (if you’re inside it, cd .. steps up one level), then:

mkdir neon-dodge
cd neon-dodge
claude

1. Enter plan mode. Press Shift+Tab until you see ⏸ plan mode on.

2. Describe your game. Use the build order from lesson 2.1:

Plan a browser game I can play by opening one HTML file.
Goal: a "neon dodge" game. I move a ship left and right with the arrow keys
(and by tapping on phones) to dodge falling blocks. The speed goes up over
time. Score = seconds survived.
Rules: plain HTML, CSS and JavaScript, no libraries, no build tools, works
by double-clicking index.html.
Done means: I can play a full round, lose, see my score, and restart.
Give me the plan as a short numbered list of steps.

What you’ll see: Claude might ask a question or two (it’s checking assumptions instead of guessing, which is good), then shows a numbered plan: maybe set up the canvas, draw the ship, add controls, spawn blocks, detect collisions, score, game over screen. It doesn’t create any files.

3. Push back. Read the plan like a director. Change at least one thing:

Two changes: drop the sound effects for now, and add a pause key (P).
Also, the first version should be playable after the first three steps,
so I can test early.

What you’ll see: a revised plan. Still no files touched. This is the cheapest moment to get it right.

4. Save the plan. Approve the plan. Claude will want to start building: tell it to save the plan first, as a checklist file:

Before building anything, save this plan to plan.md as a checklist. Then stop.

What you’ll see: a plan.md file with checkboxes. That file survives everything, so you can pick up the plan in any future session. Level 3 builds the game from it.

Think harder on the hard stuff

For a tricky decision, add the word ultrathink anywhere in your message: “ultrathink: what’s the simplest way to make the difficulty feel fair?” Claude reasons more deeply for that one message. It’s slower and uses more of your plan’s usage, so save it for real head-scratchers.

When Claude gets confused

• It starts writing code before you approved. Check the status line: you may not be in plan mode. Press Esc, then Shift+Tab until it shows plan mode.
• The plan is way bigger than your idea (accounts, leaderboards, a shop…). Claude sometimes over-scopes. Say “keep it minimal, only what I described” and it’ll trim.
• The plan has steps you don’t understand. Ask: “Explain step 4 like I’ve never coded.” No shame in it; it’s how directors learn the job.

Did it work?

• You entered plan mode with Shift+Tab
• Claude proposed a plan without changing any files
• You changed at least one thing in the plan
• plan.md exists with the plan as a checklist