Plan mode — read-only first

Claude can be mid-edit in ten seconds. Plan first.

You'd never let a contractor start demolition off a one-line text. Plan mode is the briefing meeting — two keypresses away.

A mode where Claude can look but not touch.

Claude reads files, searches the codebase, works out an approach — and cannot edit anything until you approve. The restriction lives in the permission system, not in etiquette.

Two keypresses, a prefix, or a flag.

Shift+Tab Shift+Tab    # cycle into plan mode

/plan <your request>   # one message in plan mode

$ claude --permission-mode plan
# the studio's opener for any repo
# Claude has never seen

Plans persist as markdown under ~/.claude/plans/ — a plan you commission before lunch is still waiting in the afternoon.

Four slots, filled every time.

• 01Context — what the project is, in one line
• 02Goal — the one change this session exists for
• 03Constraints — what's off-limits, named explicitly
• 04Done — what you'll check to call it finished

The studio kickoff.

Context: static HTML+CSS site, no build step.
Goal: add a three-tier pricing section to
index.html.
Constraints: reuse the CSS variables in
style.css, no JavaScript, no new files.
Done looks like: the section renders below
Selected work.
Propose a plan first - including what you
will NOT touch.

An approvable plan names what it will NOT do.

Three things, every time: the files it will touch, the order of operations, and the non-goals stated out loud. "I'll improve the styling" names no files. A plan missing any of the three gets another round of questions, not approval.

Planning is not slowing down.

The plan-mode ritual.

• Shift+Tab twice before any non-trivial task
• Fill all four kickoff slots — context, goal, constraints, done
• Check the plan names files, order, and non-goals
• Look for the Untouched list — hold the plan to it
• Client repo? Set defaultMode "plan" in .claude/settings.json

One idea from one lesson.

Track 1 (23 lessons) is free.