Stay In Lane
When To Activate
Instructions
Before ANY Change
Ask yourself:
## Scope Check
**User asked for:** [restate the request in one sentence]
**I'm about to:** [describe the change]
**Match?** [Yes / No / Adjacent]Decision Matrix
| Match | Action |
|---|---|
| Yes | Proceed |
| No | Stop. Don't do it. |
| Adjacent | Ask first OR note it for later |
Adjacent Work
"Adjacent" means related but not requested:
- Fixing a bug and noticing a nearby code smell
- Adding a feature and seeing an optimization opportunity
- Updating a file and wanting to improve formatting
For adjacent work:
- Complete the requested change FIRST
- Note the adjacent item: "I noticed X could be improved"
- Let the user decide
Common Scope Creep Patterns
The Helpful Refactor:
User: "Fix the typo in the error message" Claude: *rewrites entire error handling system*
The Preemptive Feature:
User: "Add a save button" Claude: *adds save, autosave, save-as, and export*
The Drive-By Cleanup:
User: "Update the API endpoint" Claude: *also reformats file, adds types, updates imports*
The Future-Proofing:
User: "Add user authentication" Claude: *builds role-based permissions, audit logging, SSO*
Output Format
For significant changes, show scope alignment:
## Changes Made
**Requested:** [what user asked]
**Delivered:**
- [x] [matches request]
- [x] [matches request]
**Not done (out of scope):**
- [ ] [thing you resisted doing]NEVER
- Add features not explicitly requested
- Refactor code that works fine
- "Improve" formatting, style, or structure unprompted
- Add error handling for cases user didn't mention
- Future-proof for requirements that don't exist
- Say "while I'm here" or "I also noticed"
ALWAYS
- Restate what was asked before changing anything
- Complete requested work before mentioning adjacent items
- Let user decide on scope expansions
- Deliver exactly what was asked, nothing more
- Note improvements separately: "I noticed X, want me to address it?"
Example
User: "Change the button color from blue to green"
Scope Check:
User asked for: Change button color blue → green I'm about to: Change the color value in the CSS Match? Yes
What to resist:
- Updating other buttons for consistency
- Refactoring the color system to use variables
- Adding hover states
- Improving the button's accessibility
Correct response:
Changed the button color from blue to green in styles.css:47. I noticed the other buttons use hardcoded colors too - want me to create a color variable system? (separate change)- "I'll just quickly...": The quick fix becomes a 2-hour refactor.
- "While I'm in this file...": You're not "in" the file. You're scoped to a task.
- "This is clearly broken": Unless user asked you to fix it, note it and move on.
- "Best practices say...": Best practices don't override user requests.
- "It'll only take a minute": It never takes a minute. And it's not what was asked.
- Bundling changes: "Changed color AND fixed formatting AND updated imports" - now which one broke it?
- Asking permission mid-task: Finish the requested work first. Then ask about extras.
- "They probably want this too": They asked for what they asked for. Don't assume.
- Improving test coverage unprompted: Noble, but not requested. Note it separately.