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.

Build Health Auditor (L3 Worker)

Specialized worker auditing build health and code quality tooling.

Purpose & Scope

• Worker in ln-620 coordinator pipeline - invoked by ln-620-codebase-auditor
• Audit codebase for build health issues (Category 2: Critical Priority)
• Check compiler/linter errors, deprecation warnings, type errors, failed tests, build config
• Return structured findings to coordinator with severity, location, effort, recommendations
• Calculate compliance score (X/10) for Build Health category

Inputs (from Coordinator)

MANDATORY READ: Load shared/references/audit_worker_core_contract.md.

Receives contextStore with: tech_stack (including build_tool, test_framework), best_practices, principles, codebase_root, output_dir.

Workflow

MANDATORY READ: Load shared/references/two_layer_detection.md for detection methodology.

1. Parse Context: Extract tech stack, build tools, test framework, output_dir from contextStore
2. Run Build Checks (Layer 1): Execute compiler, linter, type checker, tests (see Audit Rules below)
3. Analyze Output Context (Layer 2): For deprecation warnings — read notice to determine if removal is imminent or distant. For config issues — check if dev-only or production config.
4. Collect Findings: Record each violation with severity, location, effort, recommendation
5. Calculate Score: Count violations by severity, calculate compliance score (X/10)
6. Write Report: Build full markdown report in memory per shared/templates/audit_worker_report_template.md, write to {output_dir}/622-build.md in single Write call
7. Return Summary: Return minimal summary to coordinator (see Output Format)

Audit Rules (Priority: CRITICAL)

MANDATORY READ: Load shared/references/ci_tool_detection.md for build commands, linter commands, type checker commands, and test framework commands per ecosystem.

1. Compiler/Linter Errors

What: Syntax errors, compilation failures, linter rule violations

Detection: Use ci_tool_detection.md Command Registry (Build + Linters sections). Check exit code, parse stderr for errors. Use JSON output flags where available.

Linters: Use ci_tool_detection.md Linters table. Use --format json / --output-format json for structured output.

Severity:

• CRITICAL: Compilation fails, cannot build project
• HIGH: Linter errors (not warnings)
• MEDIUM: Linter warnings
• LOW: Stylistic linter warnings (formatting)

Recommendation: Fix errors before proceeding, configure linter rules, add pre-commit hooks

Effort: S-M (fix syntax error vs refactor code structure)

2. Deprecation Warnings

What: Usage of deprecated APIs, libraries, or language features

Detection:

• Compiler warnings: DeprecationWarning, @deprecated in stack trace
• Dependency warnings: npm outdated, pip list --outdated
• Static analysis: Grep for @deprecated annotations

Severity:

• CRITICAL: Deprecated API removed in next major version (imminent breakage)
• HIGH: Deprecated with migration path available
• MEDIUM: Deprecated but still supported for 1+ year
• LOW: Soft deprecation (no removal timeline)

Recommendation: Migrate to recommended API, update dependencies, refactor code

Effort: M-L (depends on API complexity and usage frequency)

3. Type Errors

What: Type mismatches, missing type annotations, type checker failures

Detection: Use ci_tool_detection.md Command Registry (Type Checkers section).

Severity:

• CRITICAL: Type error prevents compilation (tsc fails, cargo check fails)
• HIGH: Runtime type error likely (implicit any, missing type guards)
• MEDIUM: Missing type annotations (code works but untyped)
• LOW: Overly permissive types (any, unknown without narrowing)

Recommendation: Add type annotations, enable strict mode, use type guards

Effort: S-M (add types to single file vs refactor entire module)

4. Failed or Skipped Tests

What: Test suite failures, skipped tests, missing test coverage

Detection: Use ci_tool_detection.md Command Registry (Test Frameworks section). Use JSON output flags for structured parsing.

Severity:

• CRITICAL: Test failures in CI/production code
• HIGH: Skipped tests for critical features (payment, auth)
• MEDIUM: Skipped tests for non-critical features
• LOW: Skipped tests with "TODO" comment (acknowledged debt)

Recommendation: Fix failing tests, remove skip markers, add missing tests

Effort: S-M (update test assertion vs redesign test strategy)

5. Build Configuration Issues

What: Misconfigured build tools, missing scripts, incorrect paths

Detection:

• Missing build scripts in package.json, Makefile, build.gradle
• Incorrect paths in tsconfig.json, webpack.config.js, Cargo.toml
• Missing environment-specific configs (dev, staging, prod)
• Unused or conflicting build dependencies

Severity:

• CRITICAL: Build fails due to misconfiguration
• HIGH: Build succeeds but outputs incorrect artifacts (wrong target, missing assets)
• MEDIUM: Suboptimal config (no minification, missing source maps)
• LOW: Unused config options

Recommendation: Fix config paths, add missing build scripts, optimize build settings

Effort: S-M (update config file vs redesign build pipeline)

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}/622-build.md with category: "Build Health" and checks: compilation_errors, linter_warnings, type_errors, test_failures, build_config.

Return summary to coordinator:

Report written: docs/project/.audit/ln-620/{YYYY-MM-DD}/622-build.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 violations only; coordinator creates task for user to fix
• Tech stack aware: Use contextStore to run appropriate build commands (npm vs cargo vs gradle)
• Exit code checking: Always check exit code (0 = success, non-zero = failure)
• Timeout handling: Set timeout for build/test commands (default 5 minutes)
• Environment aware: Run in CI mode if detected (no interactive prompts)

Definition of Done

MANDATORY READ: Load shared/references/audit_worker_core_contract.md.

• contextStore parsed successfully (including output_dir)
• All 5 build checks completed (compiler, linter, type checker, tests, config)
• Findings collected with severity, location, effort, recommendation
• Score calculated using penalty algorithm
• Report written to {output_dir}/622-build.md (atomic single Write call)
• Summary returned to coordinator

Reference Files

• Audit output schema: shared/references/audit_output_schema.md
• CI tool detection: shared/references/ci_tool_detection.md
• Build audit rules: references/build_rules.md

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Version: 3.0.0 Last Updated: 2025-12-23