Code Quality Enforcement

Invariant Principles

1. Shortcuts compound - Every any type, swallowed error, and skipped test becomes someone's 3am incident.
2. Pre-existing issues are your issues - Discovering a bug during work means fixing it, not routing around it.
3. Tests prove behavior - Coverage metrics mean nothing. Assertions that verify actual outcomes mean everything.
4. Patterns before invention - Read existing code first. Match conventions. Novel approaches require justification.
5. Production-quality, not "works" - "Technically passes" is not the bar. "Confidently deployable" is.

Inputs

Outputs

Reasoning Schema

Prohibitions

Required Behaviors

Pre-Existing Issues Protocol

When discovering issues in touched code:

1. Flag immediately - Note the issue in your response
2. Ask about fixing - "Found X issue. Fix now or track separately?"
3. Default to fix - User usually wants it fixed
4. Never silently ignore - Routing around bugs creates more bugs

Quality Checklist

• Matches existing codebase patterns
• No items from FORBIDDEN list
• Error handling is explicit and complete
• Tests have meaningful assertions
• Test assertions are Level 4+ on the Assertion Strength Ladder (patterns/assertion-quality-standard.md)
• Full Assertion Principle enforced: ALL output tested with exact equality (assert result == expected), never substring checks; for dynamic output, construct full expected value dynamically
• No bare substring checks on any output (assert "X" in result is BANNED -- static or dynamic)
• No partial assertions on dynamic output (construct full expected, do not use membership checks)
• No mock.ANY in call assertions (BANNED -- construct expected argument)
• Every mock call asserted with ALL args; call count verified
• No length/existence-only assertions
• No partial-to-partial upgrades (Pattern 10: replacing one BANNED assertion with another is not a fix)
• No hallucinated APIs: method calls, imports, and config keys verified against actual library/framework
• AI-generated code has had API signatures spot-checked against source or documentation
• Pre-existing issues addressed or explicitly tracked
• Would confidently deploy this

Self-Check

• Every error path handled explicitly
• No any types introduced
• No try-catch swallowing errors
• Tests verify behavior, not just run
• Test assertions are Level 4+ on the Assertion Strength Ladder (patterns/assertion-quality-standard.md)
• ALL output tested with exact equality (assert result == expected_complete_output); for dynamic output, construct full expected value dynamically
• No bare substring checks on any output (assert "X" in result is BANNED -- static or dynamic)
• No mock.ANY in call assertions (BANNED -- construct expected argument dynamically)
• Every mock call asserted with ALL args; call count verified
• No length/existence-only assertions
• No tautological assertions (assert result == func(same_input))
• Pre-existing issues flagged to user
• Code matches existing patterns

<FINAL_EMPHASIS> Zero shortcuts. Zero swallowed errors. Zero skipped assertions. Code that ships must be code you would defend at 3am. If any checklist item is unchecked, it is not done. </FINAL_EMPHASIS>