Ln 620 Codebase Auditor

Codebase Auditor (L2 Coordinator)

Coordinates 9 specialized audit workers to perform comprehensive codebase quality analysis.

Purpose & Scope

• Coordinates 9 audit workers (ln-621 through ln-629) running in parallel
• Research current best practices for detected tech stack via MCP tools ONCE
• Pass shared context to all workers (token-efficient)
• Aggregate worker results into single consolidated report
• Create single refactoring task in Linear under Epic 0 with all findings
• Manual invocation by user; not part of Story pipeline

Workflow

1. Discovery: Load tech_stack.md, principles.md, package manifests, auto-discover Team ID
2. Research: Query MCP tools for current best practices per major dependency ONCE
3. Build Context: Create contextStore with best practices + tech stack metadata
4. Domain Discovery: Detect project domains from folder structure (NEW)
5. Delegate: Two-stage delegation - global workers + domain-aware workers (UPDATED)
6. Aggregate: Collect worker results, group by domain, calculate scores
7. Generate Report: Build consolidated report with Domain Health Summary, Findings by Domain
8. Create Task: Create Linear task in Epic 0 titled "Codebase Refactoring: [YYYY-MM-DD]"

Phase 1: Discovery

Load project metadata:

• docs/project/tech_stack.md - detect tech stack for research
• docs/principles.md - project-specific quality principles
• Package manifests: package.json, requirements.txt, go.mod, Cargo.toml
• Auto-discover Team ID from docs/tasks/kanban_board.md

Extract metadata only (not full codebase scan):

• Programming language(s)
• Major frameworks/libraries
• Database system(s)
• Build tools
• Test framework(s)

Phase 2: Research Best Practices (ONCE)

For each major dependency identified in Phase 1:

1. Use mcp__Ref__ref_search_documentation for current best practices
2. Use mcp__context7__get-library-docs for up-to-date library documentation
3. Focus areas by technology type:

Build contextStore:

{
  "tech_stack": {...},
  "best_practices": {...},
  "principles": {...},
  "codebase_root": "..."
}

Phase 3: Domain Discovery

Purpose: Detect project domains from folder structure for domain-aware auditing.

Algorithm:

1. Priority 1: Explicit domain folders

   • Check for: src/domains/*/, src/features/*/, src/modules/*/
   • Monorepo patterns: packages/*/, libs/*/, apps/*/
   • If found (>1 match) → use these as domains

2. Priority 2: Top-level src/ folders*

   • List folders: src/users/, src/orders/, src/payments/
   • Exclude infrastructure: utils, shared, common, lib, helpers, config, types, interfaces, constants, middleware, infrastructure, core
   • If remaining >1 → use as domains

3. Priority 3: Fallback to global mode

   • If <2 domains detected → domain_mode = "global"
   • All workers scan entire codebase (backward-compatible behavior)

Heuristics for domain detection:

Output:

{
  "domain_mode": "domain-aware",
  "all_domains": [
    {"name": "users", "path": "src/users", "file_count": 45, "is_shared": false},
    {"name": "orders", "path": "src/orders", "file_count": 32, "is_shared": false},
    {"name": "shared", "path": "src/shared", "file_count": 15, "is_shared": true}
  ]
}

Shared folder handling:

• Folders named shared, common, utils, lib, core → mark is_shared: true
• Shared code audited but grouped separately in report
• Does not affect domain-specific scores

Phase 4: Delegate to Workers

CRITICAL: All delegations use Task tool with subagent_type: "general-purpose" for context isolation.

Prompt template:

Task(description: "Audit via ln-62X",
     prompt: "Execute ln-62X-{worker}-auditor. Read skill from ln-62X-{worker}-auditor/SKILL.md. Context: {contextStore}",
     subagent_type: "general-purpose")

Anti-Patterns:

• ❌ Direct Skill tool invocation without Task wrapper
• ❌ Any execution bypassing subagent context isolation

Phase 4a: Global Workers (PARALLEL)

Global workers scan entire codebase (not domain-aware):

Invocation (7 workers in PARALLEL):

FOR EACH worker IN [ln-621, ln-622, ln-625, ln-626, ln-627, ln-628, ln-629]:
  Task(description: "Audit via " + worker,
       prompt: "Execute " + worker + ". Read skill. Context: " + JSON.stringify(contextStore),
       subagent_type: "general-purpose")

Phase 4b: Domain-Aware Workers (PARALLEL per domain)

Domain-aware workers run once per domain:

Invocation (2 workers × N domains):

IF domain_mode == "domain-aware":
  FOR EACH domain IN all_domains:
    domain_context = {
      ...contextStore,
      domain_mode: "domain-aware",
      current_domain: { name: domain.name, path: domain.path }
    }
    // Invoke both workers for this domain
    Skill(skill="ln-623-code-principles-auditor", args=JSON.stringify(domain_context))
    Skill(skill="ln-624-code-quality-auditor", args=JSON.stringify(domain_context))
ELSE:
  // Fallback: invoke once for entire codebase (global mode)
  Skill(skill="ln-623-code-principles-auditor", args=JSON.stringify(contextStore))
  Skill(skill="ln-624-code-quality-auditor", args=JSON.stringify(contextStore))

Parallelism strategy:

• Phase 4a: All 7 global workers run in PARALLEL
• Phase 4b: All (2 × N) domain-aware invocations run in PARALLEL
• Example: 3 domains → 6 invocations (ln-363×3 + ln-364×3) in single message

Phase 5: Aggregate Results

Collect results from workers:

Global worker output (unchanged):

{
  "category": "Security",
  "score": 7,
  "total_issues": 5,
  "critical": 1,
  "high": 2,
  "medium": 2,
  "low": 0,
  "findings": [...]
}

Domain-aware worker output (NEW):

{
  "category": "Architecture & Design",
  "score": 6,
  "domain": "users",
  "scan_path": "src/users",
  "total_issues": 4,
  "critical": 1,
  "high": 2,
  "medium": 1,
  "low": 0,
  "findings": [
    {
      "severity": "CRITICAL",
      "location": "src/users/controllers/UserController.ts:45",
      "issue": "Controller directly uses Repository",
      "principle": "Layer Separation (Clean Architecture)",
      "recommendation": "Create UserService",
      "effort": "L",
      "domain": "users"
    }
  ]
}

Aggregation steps:

1. Global workers → merge findings (as before)
2. Domain-aware workers → group by domain.name:
   • Calculate domain-level scores (Architecture + Quality per domain)
   • Build Domain Health Summary table
3. Overall score → average of all category scores (Architecture/Quality averaged across domains)
4. Severity summary → sum critical/high/medium/low across ALL workers
5. Findings grouping:
   • Global categories (Security, Build, etc.) → single table
   • Domain-aware categories → subtables per domain

Output Format

## Codebase Audit Report - [DATE]

### Executive Summary
[2-3 sentences on overall codebase health, major risks, and key strengths]

### Compliance Score

| Category | Score | Notes |
|----------|-------|-------|
| Security | X/10 | ... |
| Build Health | X/10 | ... |
| Architecture & Design | X/10 | ... |
| Code Quality | X/10 | ... |
| Dependencies & Reuse | X/10 | ... |
| Dead Code | X/10 | ... |
| Observability | X/10 | ... |
| Concurrency | X/10 | ... |
| Lifecycle | X/10 | ... |
| **Overall** | **X/10** | |

### Severity Summary

| Severity | Count |
|----------|-------|
| Critical | X |
| High | X |
| Medium | X |
| Low | X |

### Domain Health Summary (NEW - if domain_mode="domain-aware")

| Domain | Files | Arch Score | Quality Score | Issues |
|--------|-------|------------|---------------|--------|
| users | 45 | 7/10 | 8/10 | 5 |
| orders | 32 | 5/10 | 6/10 | 8 |
| payments | 28 | 8/10 | 7/10 | 3 |
| shared | 15 | 6/10 | 9/10 | 2 |
| **Total** | **120** | **6.5/10** | **7.5/10** | **18** |

### Strengths
- [What's done well in this codebase]
- [Good patterns and practices identified]

### Findings by Category

#### 1. Security (Global)

| Severity | Location | Issue | Principle Violated | Recommendation | Effort |
|----------|----------|-------|-------------------|----------------|--------|
| CRITICAL | src/api/auth.ts:45 | Hardcoded API key | Secrets Management | Move to .env | S |

#### 2. Build Health (Global)

| Severity | Location | Issue | Principle Violated | Recommendation | Effort |
|----------|----------|-------|-------------------|----------------|--------|
| CRITICAL | Multiple files | TypeScript strict errors | Type Safety | Fix types | S |

#### 3. Architecture & Design (Domain-Grouped)

##### Domain: users (src/users/)

| Severity | Location | Issue | Principle Violated | Recommendation | Effort |
|----------|----------|-------|-------------------|----------------|--------|
| CRITICAL | UserController.ts:12 | Controller→Repository bypass | Layer Separation | Add Service layer | L |

##### Domain: orders (src/orders/)

| Severity | Location | Issue | Principle Violated | Recommendation | Effort |
|----------|----------|-------|-------------------|----------------|--------|
| HIGH | OrderService.ts:45 | DRY violation (duplicate validation) | DRY Principle | Extract to validators/ | M |

##### Domain: shared (src/shared/)

| Severity | Location | Issue | Principle Violated | Recommendation | Effort |
|----------|----------|-------|-------------------|----------------|--------|
| MEDIUM | utils.ts:78 | TODO older than 6 months | Code Hygiene | Complete or remove | S |

#### 4. Code Quality (Domain-Grouped)

##### Domain: users (src/users/)

| Severity | Location | Issue | Principle Violated | Recommendation | Effort |
|----------|----------|-------|-------------------|----------------|--------|
| HIGH | UserService.ts:120 | Complexity 25 | Maintainability | Split function | M |

... (continue for remaining global categories: 5-9)

### Recommended Actions (Priority-Sorted)

| Priority | Category | Domain | Location | Issue | Recommendation | Effort |
|----------|----------|--------|----------|-------|----------------|--------|
| CRITICAL | Security | - | src/api/auth.ts:45 | Hardcoded API key | Move to .env | S |
| CRITICAL | Architecture | users | UserController.ts:12 | Controller→Repository bypass | Add Service layer | L |
| CRITICAL | Build | - | Multiple files | TypeScript strict errors | Fix types | S |
| HIGH | Architecture | orders | OrderService.ts:45 | DRY violation | Extract to validators/ | M |
| HIGH | Code Quality | users | UserService.ts:120 | Complexity 25 | Split function | M |

### Priority Actions
1. Fix all Critical issues before next release
2. Address High issues within current sprint
3. Plan Medium issues for technical debt sprint
4. Track Low issues in backlog

### Sources Consulted
- [Framework] best practices: [URL from MCP Ref]
- [Library] documentation: [URL from Context7]

Phase 6: Create Linear Task

Create task in Epic 0:

• Title: Codebase Refactoring: [YYYY-MM-DD]
• Description: Full report from Phase 5 (markdown format)
• Team: Auto-discovered from kanban_board.md
• Epic: 0 (technical debt / refactoring epic)
• Labels: refactoring, technical-debt, audit
• Priority: Based on highest severity findings (Critical → Urgent, High → High, etc.)

Critical Rules

• Two-stage delegation: Global workers (7) + Domain-aware workers (2 × N domains)
• Domain discovery: Auto-detect domains from folder structure; fallback to global mode
• Parallel execution: All workers (global + domain-aware) run in PARALLEL
• Single context gathering: Research best practices ONCE, pass contextStore to all workers
• Metadata-only loading: Coordinator loads metadata only; workers load full file contents
• Domain-grouped output: Architecture & Code Quality findings grouped by domain
• Language preservation: Task description in project's language (EN/RU from kanban_board.md)
• Single task: Create ONE task with all findings; do not create multiple tasks
• Do not audit: Coordinator orchestrates only; audit logic lives in workers

Definition of Done

• Best practices researched via MCP tools for major dependencies
• Domain discovery completed (domain_mode determined)
• contextStore built with tech stack + best practices + domain info
• Global workers (7) invoked in PARALLEL
• Domain-aware workers (2 × N domains) invoked in PARALLEL
• All workers completed successfully (or reported errors)
• Results aggregated with domain grouping
• Domain Health Summary built (if domain_mode="domain-aware")
• Compliance score (X/10) calculated per category + overall
• Executive Summary and Strengths sections included
• Linear task created in Epic 0 with full report
• Sources consulted listed with URLs

Workers

See individual worker SKILL.md files for detailed audit rules:

• ln-621-security-auditor
• ln-622-build-auditor
• ln-623-code-principles-auditor
• ln-624-code-quality-auditor
• ln-625-dependencies-auditor
• ln-626-dead-code-auditor
• ln-627-observability-auditor
• ln-628-concurrency-auditor
• ln-629-lifecycle-auditor

Reference Files

• Principles: docs/principles.md
• Tech stack: docs/project/tech_stack.md
• Kanban board: docs/tasks/kanban_board.md

Version: 5.0.0 Last Updated: 2025-12-23