file-justification

name	file-justification
description	Guide and workflow for File Justification Protocol. Use when you need File Justification Protocol.

File Justification Protocol

Purpose: Before creating or modifying ANY file, you MUST document the justification to prevent unnecessary file creation and ensure changes are well-reasoned.

When This Protocol Applies

• Creating a NEW file (highest scrutiny)
• Modifying an EXISTING file
• All PR changes (each file touched needs justification)

Justification Template

For EACH file you touch, document:

### File: <filename>

**GOAL**: What are you trying to achieve?
**MODIFICATION**: What specific change are you making?
**NECESSITY**: Why is this change required? Why can't it be done differently?
**INTEGRATION PROOF**: How does this integrate with existing code?

New File Creation - Extreme Scrutiny

Default: NO NEW FILES - You must prove why integration into existing files is impossible.

Pre-Write Checklist (MANDATORY before creating any new file)

1. Assume existing files can handle it - Search for similar functionality
2. Identify integration targets - Which existing files could contain this code?
3. Attempt integration first - Try adding to existing file before creating new
4. Document why integration failed - Concrete reason, not "cleaner this way"

Integration Hierarchy (try in order)

1. Existing file with similar functionality
2. Existing utility/helper file
3. Existing __init__.py
4. Existing test file (for test code)
5. Existing class as a method
6. Config file
7. LAST RESORT: New file (with full justification)

Examples

Good Justification (Modifying Existing)

### File: mvp_site/llm_response.py

**GOAL**: Add backward compatibility for outcome_resolution field
**MODIFICATION**: Add property that falls back to outcome_resolution when action_resolution is missing
**NECESSITY**: API clients already use action_resolution; changing the field name would break them
**INTEGRATION PROOF**: Property pattern matches existing properties in this class (lines 45-67)

Good Justification (New File - Justified)

### File: mvp_site/action_resolution_utils.py (NEW)

**GOAL**: Centralize action_resolution/outcome_resolution fallback logic
**MODIFICATION**: Create helper module with get_action_resolution() function
**NECESSITY**: Same logic duplicated in llm_response.py (22 lines) and world_logic.py (13 lines)
**INTEGRATION PROOF**:
- Could not add to llm_response.py - world_logic.py would create circular import
- Could not add to world_logic.py - llm_response.py would create circular import
- New utils file breaks the dependency cycle

Bad Justification (Rejected)

### File: mvp_site/new_helper.py (NEW)

**GOAL**: Add helper function
**MODIFICATION**: Create new file with helper
**NECESSITY**: Cleaner to have it separate  <-- NOT VALID
**INTEGRATION PROOF**: None attempted  <-- MUST ATTEMPT

File Placement Rules

If a new file is justified, place it correctly:

Code Type	Location
Python module	mvp_site/ or appropriate submodule
Scripts	scripts/
Tests	mvp_site/tests/
Commands	.claude/commands/
Skills	.claude/skills/

NEVER create new files in project root.

Banned Patterns

• *_v2.py - Edit existing file
• *_new.py - Edit existing file
• *_backup.py - Use git
• *_old.py - Delete and replace

Quick Reference

Before ANY file operation:

1. What existing file could contain this? (Search first)
2. Why can't I add this to that file? (Valid reason required)
3. Have I documented GOAL/MODIFICATION/NECESSITY/INTEGRATION PROOF?

If you cannot answer these questions, do not create the file.