Foundations
Plan Mode: Think Before You Build
One toggle that stops Claude Code from sprinting in the wrong direction. Saves 30-40% on tokens. Takes two seconds to turn on.
On this page (6 sections)
The most expensive mistake in Claude Code is letting it start coding without alignment.
You send a big prompt. Claude Code starts immediately. Three files in, you realize it chose the wrong approach. Now you're spending tokens to undo work that shouldn't have been done in the first place. I've done this more times than I want to admit.
Plan mode fixes this. Claude Code outlines its full approach first, you review it, optionally correct it, then it executes. One toggle. Massive impact on complex tasks.
How to Activate Plan Mode
Three ways:
Shift+Tab is the one to memorize. Toggles plan mode on/off. When it's active you'll see an indicator in the prompt.
Type "plan" or "think about" in your prompt. Including either phrase nudges Claude Code toward planning behavior even without the toggle. Useful when you just want one-off planning without changing the mode.
CLAUDE.md instruction. Add Always plan before implementing changes that touch more than 2 files to your project config and planning becomes the automatic default for anything substantial.
When Plan Mode Is Worth It
Multi-file refactors. Anything touching 3+ files. The plan catches dependency chains you'd miss yourself and surfaces them before a single line is written.
Architectural decisions. "Should I use Server Components or Client Components here?" Let it reason through the tradeoffs in the plan. Then you decide. Then it codes.
Unfamiliar codebases. First week on a new project? Plan mode forces Claude Code to read and understand the existing code before it writes anything. This alone has saved me from embarrassing PRs.
Complex features. New authentication flow, payment integration, database migration. Anything with 5+ moving parts deserves a plan.
When to Skip Plan Mode
Not everything needs planning. Overthinking simple tasks just adds friction.
Quick edits. "Fix the typo in the header component." Just execute.
Single-file changes. "Add a loading spinner to this button." No plan needed.
Simple questions. "What does this function do?" Plan mode adds nothing here, literally nothing.
One-liner fixes. "Change the primary color to blue-600." Just do it.
Rough rule: fewer than 3 steps, skip the plan.
The Token Math (This Is Why It Actually Saves Money)
Here's the counterintuitive part. Plan mode adds an extra step, which feels like it should cost more. It doesn't.
Without planning, Claude Code might write 500 lines of code, realize the approach was wrong, then rewrite 400 of those lines. That's 900 lines of output tokens billed.
With planning, it spends maybe 50 tokens on a plan, you catch the problem, it writes 500 lines correctly the first time. That's 550 tokens total. You just saved 40%. The plan paid for itself 7 times over.
Plan Mode + Extended Thinking
When plan mode is on and extended thinking is enabled (Option+T on Mac), Claude Code does its deepest reasoning before touching a single file. It considers edge cases, alternative approaches, and potential problems you haven't even thought to ask about.
For complex architectural work, this combination is worth every extra token. For everything else, plan mode alone is enough.
New guides, when they ship
One email, roughly weekly. CLAUDE.md templates, workflows I actually use, and the cut-for-length stuff that does not make the public guides. One-click unsubscribe.
Or follow on Substack