Case Study Tab Indicator Removal

Case Study: Tab Indicator Inset Removal

Type: REFACTOR Skills: code-foundations → cc-developer-character → cc-refactoring-guidance Focus: Discipline recovery and systematic feature removal

Why This Case Study Matters

This example shows the discipline enforcement aspect of code-foundations:

1. User intervention - Claude started editing before being asked to use the skill
2. Honest self-assessment - cc-developer-character acknowledged the premature edit
3. Systematic plan - cc-refactoring-guidance created a step-by-step removal plan
4. Verification after each step - Build checks between each file change

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The Problem

Remove the TabIndicatorInset feature from the codebase. This feature touched:

• Config types and parsing
• Layout calculation logic
• Window move operations
• Tests

Claude started making edits before being asked to use the systematic approach.

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The Flow

User: "remove the tab indicator inset feature"
Claude: [starts editing types.go]

User: "please use the code-foundations skill to remove this"

→ code-foundations classifies as REFACTOR
→ cc-developer-character runs self-assessment
  → Acknowledges: "I already made one edit before being asked to use the skill"
→ cc-refactoring-guidance creates removal plan

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Developer Character Self-Assessment

The skill caught the discipline slip:

Check	Assessment
Understanding vs hoping	✓ Traced feature through git history and all files
Intellectual honesty	"This is a multi-file removal... needs systematic approach"
Discipline	"Will follow refactoring guidance - one change at a time"
Humility	"I already made one edit before being asked to use the skill"

Key insight: The skill didn't hide the premature action - it acknowledged it and committed to proceeding properly.

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Refactoring Plan

cc-refactoring-guidance produced this systematic plan:

Step	File	Change	Verify
1	config/types.go	Remove TabIndicatorInset field	✅ Done
2	config/config.go	Remove GetTabIndicatorInset()	Build
3	layout/windows.go	Remove params + inset logic	Build
4	layout/apply.go	Update call sites	Build
5	window/move.go	Update call sites	Build
6	layout/windows_test.go	Remove related tests	Build + Test

One change at a time, verify after each step.

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CHECKER Gates (Post-Refactoring)

After all changes and tests passed, CHECKER gates verified quality:

cc-control-flow-quality

Check	Result
Nesting depth	Max 2 levels (PASS)
Boolean expressions	No complex expressions
Switch statements	Simple stack modes
Loop structures	Clean

cc-routine-and-class-design

Check	Result
Parameter count	9 parameters (was 11) - within acceptable range
Cohesion	Functional - each function does one thing
Abstractions	Clear

Change Scope

grid-cli/internal/config/config.go       |  13 --
grid-cli/internal/config/types.go        |   1 -
grid-cli/internal/layout/apply.go        |  31 +---
grid-cli/internal/layout/windows.go      |  20 +--
grid-cli/internal/layout/windows_test.go |   6 +-
grid-cli/internal/window/move.go         |   4 +-

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What the Skill Prevented

Without Skill	With Skill
Ad-hoc edits across files	Systematic step-by-step plan
No verification between changes	Build check after each step
Hidden premature action	Honest acknowledgment
Potential missed references	Complete file inventory

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Key Takeaways

1. Skills can recover discipline - Starting wrong doesn't mean you can't correct course
2. Honest self-assessment - cc-developer-character acknowledges mistakes, doesn't hide them
3. Feature removal needs a plan - Multiple files means systematic approach
4. Verification gates - Build after each step catches errors early
5. Human-AI collaboration - User intervention triggered proper methodology
6. Quantified improvement - Parameter count reduced from 11 → 9, verified by CHECKER

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Skills Involved

Skill	Role
code-foundations	Classifies task as REFACTOR
cc-developer-character	Self-assessment catches discipline slip
cc-refactoring-guidance	Creates systematic removal plan
cc-control-flow-quality	CHECKER: Validates nesting, boolean complexity
cc-routine-and-class-design	CHECKER: Validates parameter counts, cohesion