ln-624-code-quality-auditor
Paths: File paths (
shared/,references/,../ln-*) are relative to skills repo root. If not found at CWD, locate this SKILL.md directory and go up one level for repo root.
Code Quality Auditor (L3 Worker)
Specialized worker auditing code complexity, method signatures, algorithms, and constants management.
Purpose & Scope
- Worker in ln-620 coordinator pipeline - invoked by ln-620-codebase-auditor
- Audit code quality (Categories 5+6+NEW: Medium Priority)
- Check complexity metrics, method signature quality, algorithmic efficiency, constants management
- Return structured findings with severity, location, effort, recommendations
- Calculate compliance score (X/10) for Code Quality category
Inputs (from Coordinator)
MANDATORY READ: Load shared/references/audit_worker_core_contract.md.
Receives contextStore with: tech_stack, best_practices, principles, codebase_root, output_dir.
Domain-aware: Supports domain_mode + current_domain (see audit_output_schema.md#domain-aware-worker-output).
Workflow
MANDATORY READ: Load shared/references/two_layer_detection.md for detection methodology.
- Parse context — extract fields, determine
scan_path(domain-aware if specified), extractoutput_dir - Scan codebase for violations (Layer 1)
- All Grep/Glob patterns use
scan_path(not codebase_root) - Example:
Grep(pattern="if.*if.*if", path=scan_path)for nesting detection
- All Grep/Glob patterns use
- Analyze context per candidate (Layer 2 — MANDATORY)
Layer 1 finding without Layer 2 = NOT a valid finding. Before reporting, ask: "Is this violation intentional or justified by design?"
- Cyclomatic complexity: is complexity from switch/case on enum (valid) or deeply nested conditions (bad)? Enum dispatch → downgrade to LOW or skip
- O(n²): read context — what's n? If bounded (n < 100), downgrade severity
- N+1: read ORM config — does it have eager loading configured elsewhere? Admin-only endpoint → downgrade severity
- God class: is it a config/schema/builder class? → downgrade
- Cascade depth: already traces calls (implicit Layer 2). Orchestrator function → SEB does NOT apply (see Conflict Resolution in ARCH-AI-SEB)
- Collect findings with severity, location, effort, recommendation
- Tag each finding with
domain: domain_name(if domain-aware)
- Tag each finding with
- Calculate score using penalty algorithm
- Write Report: Build full markdown report in memory per
shared/templates/audit_worker_report_template.md, write to{output_dir}/624-quality-{domain}.md(or624-quality.mdin global mode) in single Write call - Return Summary: Return minimal summary to coordinator (see Output Format)
Audit Rules (Priority: MEDIUM)
1. Cyclomatic Complexity
What: Too many decision points in single function (> 10)
Detection:
- Count if/else, switch/case, ternary, &&, ||, for, while
- Use tools:
eslint-plugin-complexity,radon(Python),gocyclo(Go)
Severity:
- HIGH: Complexity > 20 (extremely hard to test)
- MEDIUM: Complexity 11-20 (refactor recommended)
- LOW: Complexity 8-10 (acceptable but monitor)
- Downgrade when: Enum/switch dispatch, state machines, parser grammars → downgrade to LOW or skip
Recommendation: Split function, extract helper methods, use early returns
Effort: M-L (depends on complexity)
2. Deep Nesting (> 4 levels)
What: Nested if/for/while blocks too deep
Detection:
- Count indentation levels
- Pattern: if { if { if { if { if { ... } } } } }
Severity:
- HIGH: > 6 levels (unreadable)
- MEDIUM: 5-6 levels
- LOW: 4 levels
- Downgrade when: Nesting from early-return guard clauses (structurally deep but linear logic) → downgrade
Recommendation: Extract functions, use guard clauses, invert conditions
Effort: M (refactor structure)
3. Long Methods (> 50 lines)
What: Functions too long, doing too much
Detection:
- Count lines between function start and end
- Exclude comments, blank lines
Severity:
- HIGH: > 100 lines
- MEDIUM: 51-100 lines
- LOW: 40-50 lines (borderline)
- Downgrade when: Orchestrator functions with sequential delegation; data transformation pipelines → downgrade
Recommendation: Split into smaller functions, apply Single Responsibility
Effort: M (extract logic)
4. God Classes/Modules (> 500 lines)
What: Files with too many responsibilities
Detection:
- Count lines in file (exclude comments)
- Check number of public methods/functions
Severity:
- HIGH: > 1000 lines
- MEDIUM: 501-1000 lines
- LOW: 400-500 lines
- Downgrade when: Config/schema/migration files, generated code, barrel/index files → skip
Recommendation: Split into multiple files, apply separation of concerns
Effort: L (major refactor)
5. Too Many Parameters (> 5)
What: Functions with excessive parameters
Detection:
- Count function parameters
- Check constructors, methods
Severity:
- MEDIUM: 6-8 parameters
- LOW: 5 parameters (borderline)
- Downgrade when: Builder/options pattern constructor; framework-required signatures (middleware, hooks) → skip
Recommendation: Use parameter object, builder pattern, default parameters
Effort: S-M (refactor signature + calls)
6. O(n²) or Worse Algorithms
What: Inefficient nested loops over collections
Detection:
- Nested for loops:
for (i) { for (j) { ... } } - Nested array methods:
arr.map(x => arr.filter(...))
Severity:
- HIGH: O(n²) in hot path (API request handler)
- MEDIUM: O(n²) in occasional operations
- LOW: O(n²) on small datasets (n < 100)
- Downgrade when: Bounded n (n < 100 guaranteed by domain); one-time init/migration code → downgrade to LOW or skip
Recommendation: Use hash maps, optimize with single pass, use better data structures
Effort: M (algorithm redesign)
7. N+1 Query Patterns
What: ORM lazy loading causing N+1 queries
Detection:
- Find loops with database queries inside
- Check ORM patterns:
users.forEach(u => u.getPosts())
Severity:
- CRITICAL: N+1 in API endpoint (performance disaster)
- HIGH: N+1 in frequent operations
- MEDIUM: N+1 in admin panel
- Downgrade when: Admin-only endpoint called ≤1x/day → downgrade to LOW. Eager loading configured elsewhere in ORM → skip
Recommendation: Use eager loading, batch queries, JOIN
Effort: M (change ORM query)
8. Constants Management (NEW)
What: Magic numbers/strings, decentralized constants, duplicates
Detection:
| Issue | Pattern | Example |
|---|---|---|
| Magic numbers | Hardcoded numbers in conditions/calculations | if (status === 2) |
| Magic strings | Hardcoded strings in comparisons | if (role === 'admin') |
| Decentralized | Constants scattered across files | MAX_SIZE = 100 in 5 files |
| Duplicates | Same value multiple times | STATUS_ACTIVE = 1 in 3 places |
| No central file | Missing constants.ts or config.py |
No single source of truth |
Severity:
- HIGH: Magic numbers in business logic (payment amounts, statuses)
- MEDIUM: Duplicate constants (same value defined 3+ times)
- MEDIUM: No central constants file
- LOW: Magic strings in logging/debugging
- Downgrade when: HTTP status codes (200, 404, 500) → skip. Math constants (0, 1, -1) in algorithms → skip. Test data → skip
Recommendation:
- Create central constants file (
constants.ts,config.py,constants.go) - Extract magic numbers to named constants:
const STATUS_ACTIVE = 1 - Consolidate duplicates, import from central file
- Use enums for related constants
Effort: M (extract constants, update imports, consolidate)
9. Method Signature Quality
What: Poor method contracts reducing readability and maintainability
Detection:
| Issue | Pattern | Example |
|---|---|---|
| Boolean flag params | >=2 boolean params in signature | def process(data, is_async: bool, skip_validation: bool) |
| Too many optional params | >=3 optional params with defaults | def query(db, limit=10, offset=0, sort="id", order="asc") |
| Inconsistent verb naming | Different verbs for same operation type in one module | get_user() vs fetch_account() vs load_profile() |
| Unclear return type | -> dict, -> Any, -> tuple without TypedDict/NamedTuple |
def get_stats() -> dict instead of -> StatsResponse |
Severity:
- MEDIUM: Boolean flag params (use enum/strategy), unclear return types
- LOW: Too many optional params, inconsistent naming
Recommendation:
- Boolean flags: replace with enum, strategy pattern, or separate methods
- Optional params: group into config/options dataclass
- Naming: standardize verb conventions per module (
get_for sync,fetch_for async, etc.) - Return types: use TypedDict, NamedTuple, or dataclass instead of raw dict/tuple
Effort: S-M (refactor signatures + callers)
10. Side-Effect Cascade Depth
What: Functions triggering cascading chains of external side-effects (DB writes → notifications → metrics → limits).
Detection:
MANDATORY READ: shared/references/ai_ready_architecture.md for side-effect markers, false positive exclusions, and opaque sink rules.
- Glob
**/services/**/*.{py,ts,js,cs,java}to find service files - For each public function: check body for side-effect markers (per reference)
- Recursively follow called internal functions for additional markers
- Calculate max chain depth from entry point
Severity:
- HIGH: cascade_depth >= 4
- MEDIUM: cascade_depth = 3
- OK: depth <= 2
- Downgrade when: Orchestrator/coordinator functions (imports 3+ services AND delegates sequentially) → skip. Depth from opaque sinks (logging, metrics) → skip
Conflict Resolution: IF function is an orchestrator/coordinator (imports 3+ services AND delegates to them sequentially) → ARCH-AI-SEB does NOT apply. Orchestrators are EXPECTED to have multiple side-effect categories. Only flag SEB for leaf functions.
Recommendation: Refactor to flat orchestration — extract side-effects into independent sink functions. See reference.
Effort: M-L
Output: Also generate summary Pipe/Sink table per module:
| Module | Sinks (0-1) | Shallow Pipes (2) | Deep Pipes (3+) | Sink Ratio |
|---|
Scoring Algorithm
MANDATORY READ: Load shared/references/audit_worker_core_contract.md and shared/references/audit_scoring.md.
Output Format
MANDATORY READ: Load shared/references/audit_worker_core_contract.md and shared/templates/audit_worker_report_template.md.
Write report to {output_dir}/624-quality-{domain}.md (or 624-quality.md in global mode) with category: "Code Quality" and checks: cyclomatic_complexity, deep_nesting, long_methods, god_classes, too_many_params, quadratic_algorithms, n_plus_one, magic_numbers, method_signatures, cascade_depth.
Return summary to coordinator:
Report written: docs/project/.audit/ln-620/{YYYY-MM-DD}/624-quality-orders.md
Score: X.X/10 | Issues: N (C:N H:N M:N L:N)
Critical Rules
MANDATORY READ: Load shared/references/audit_worker_core_contract.md.
- Do not auto-fix: Report only
- Domain-aware scanning: If
domain_mode="domain-aware", scan ONLYscan_path(not entire codebase) - Tag findings: Include
domainfield in each finding when domain-aware - Context-aware: Small functions (n < 100) with O(n²) may be acceptable
- Constants detection: Exclude test files, configs, examples
- Metrics tools: Use existing tools when available (ESLint complexity plugin, radon, gocyclo)
Definition of Done
MANDATORY READ: Load shared/references/audit_worker_core_contract.md.
- contextStore parsed (including domain_mode, current_domain, output_dir)
- scan_path determined (domain path or codebase root)
- All 10 checks completed (scoped to scan_path):
- complexity, nesting, length, god classes, parameters, O(n²), N+1, constants, method signatures, cascade depth
- Findings collected with severity, location, effort, recommendation, domain
- Score calculated
- Report written to
{output_dir}/624-quality-{domain}.md(atomic single Write call) - Summary returned to coordinator
Reference Files
- Audit output schema:
shared/references/audit_output_schema.md
Version: 3.0.0 Last Updated: 2025-12-23