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+---
+description: "Deep codebase audit: launches specialized parallel agents to find issues, validates findings, groups into work packages, and creates GitHub issues"
+argument-hint: "<scope: full | src/ | src/synthorg/ | web/ | cli/ | docs/ | site/ | .github/ | ci | docker/> [--report-only] [--quick]"
+allowed-tools: ["Agent", "Bash", "Read", "Glob", "Grep", "WebFetch", "WebSearch", "AskUserQuestion", "mcp__github__issue_write", "mcp__github__issue_read", "mcp__github__list_issues", "mcp__github__search_issues"]
+---
+
+# /codebase-audit -- Deep Codebase Audit
+
+Launch a swarm of specialized agents to find issues across the entire codebase (or a targeted scope), validate all findings against actual code, group into developer-friendly work packages, and optionally create GitHub issues.
+
+## Key Principles (from battle-tested sessions)
+
+1. **Never present unvalidated findings** -- validation is mandatory before presenting findings to the user
+2. **Research architecture BEFORE auditing** -- agents that don't understand the system produce false positives
+3. **Skepticism is required** -- "100% clean" results are suspicious and trigger deeper investigation
+4. **Group by code proximity, NOT severity** -- work packages are what a developer would naturally fix together
+5. **No meta/tracking issues** -- every finding is a real issue or part of a real work package
+6. **Existing issue dedup happens TWICE** -- once in agent prompts, once after validation
+7. **Fix everything valid** -- no deferring, no "out of scope", no "future work"
+
+---
+
+## Phase 0: Parse Arguments & Determine Scope
+
+Parse the user's argument to determine audit scope:
+
+| Argument | Scope | Agent Categories |
+|----------|-------|------------------|
+| `full` (default) | Entire codebase | All categories |
+| `src/` or `src/synthorg/` | Python backend only | Python-focused categories |
+| `web/` | Vue dashboard only | Frontend categories |
+| `cli/` | Go CLI only | Go categories |
+| `docs/` or `site/` | Documentation/site | Docs/content categories |
+| `.github/` or `ci` | CI/CD only | CI/workflow categories |
+| `docker/` | Docker/compose only | Infrastructure categories |
+| `--report-only` | Any scope | Skip issue creation, report only |
+| `--quick` | Any scope | Skip Phase 5 deep dive on zero-finding categories |
+
+If no argument given, default to `full`.
+
+---
+
+## Phase 1: Gather Context
+
+**This phase is CRITICAL. Agents without context produce false positives.**
+
+### Step 1a: Fetch existing GitHub issues
+
+```bash
+gh issue list --repo OWNER/REPO --state open --limit 200 --json number,title,labels
+```
+
+Parse into a compact reference list: `#N: title [labels]`. This list is passed to EVERY audit agent.
+
+### Step 1b: Research project architecture
+
+Read key architectural files to build context that agents need. At minimum:
+
+1. **CLAUDE.md** (already in context) -- project conventions, code standards, testing rules
+2. **Observability stack** -- read `src/synthorg/observability/__init__.py`, `_logger.py`, `sinks.py`, `setup.py`, `correlation.py` to understand logging architecture, sink routing, correlation ID system
+3. **DI/wiring** -- read `src/synthorg/api/auto_wire.py` and `src/synthorg/api/lifecycle.py` to understand service initialization
+4. **Testing setup** -- read `conftest.py` files, `pyproject.toml` test config section
+5. **Design spec pointer** -- read `docs/DESIGN_SPEC.md` to know which spec pages exist
+
+Produce a **Architecture Brief** (200-400 words) summarizing:
+- Logging: how it works, sink routing rules, correlation IDs
+- DI: how services are wired, lifecycle phases
+- Testing: markers, parallelism, async mode, coverage requirements
+- Key conventions: immutability, error handling, vendor-agnostic naming
+
+This brief is injected into every agent's prompt.
+
+### Step 1c: Identify scope-specific files
+
+If scope is targeted (not `full`), glob the target directory to understand what's there.
+
+---
+
+## Phase 2: Select & Launch Audit Agents
+
+### Agent Roster
+
+Select agents based on scope. Each agent searches for ONE type of issue only.
+
+#### Python Backend Agents (scope includes `src/`)
+
+| Agent | What It Searches For |
+|-------|---------------------|
+| `missing-logging` | Business logic modules without `get_logger`, error paths that don't log before raising, state transitions without INFO logging, missing DEBUG at decision points |
+| `event-constants` | Log calls using raw strings instead of event constants from `observability/events/` |
+| `silent-errors` | Bare `except:`, `except Exception: pass`, catch blocks that swallow without logging |
+| `test-coverage` | Public modules with no corresponding test file, empty test files |
+| `flaky-tests` | Unmocked time, real asyncio.sleep in tests, timing-dependent assertions, skipped tests |
+| `wiring-lifecycle` | Incorrectly wired services, missing DI, lifecycle gaps, protocol implementations incomplete |
+| `dead-code` | Unreachable functions, unused imports, orphaned modules |
+| `todo-fixme` | Unresolved TODOs that should be tracked as issues |
+| `spec-drift` | Implementation diverging from design spec behavior |
+| `api-consistency` | REST endpoint issues: wrong status codes, missing validation, inconsistent patterns |
+| `async-patterns` | Bare create_task, missing await, blocking in async, race conditions |
+| `immutability` | Mutable defaults, in-place mutation of frozen models, missing deepcopy |
+| `missing-validation` | System boundary inputs without validation (API params, config loading, external data) |
+| `type-hints` | Missing return types, bare Any, missing NotBlankStr on identifiers |
+| `vendor-names` | Real vendor names used where generic names should be (per CLAUDE.md rules) |
+| `observability-gaps` | Sink routing gaps, correlation ID propagation drops, missing event constant modules |
+
+#### Frontend Agents (scope includes `web/`)
+
+| Agent | What It Searches For |
+|-------|---------------------|
+| `vue-dashboard` | Broken API refs, missing error handling, console.log in prod, TypeScript gaps, a11y |
+
+#### Go CLI Agents (scope includes `cli/`)
+
+| Agent | What It Searches For |
+|-------|---------------------|
+| `go-cli` | Ignored errors, resource leaks, missing error wrapping, cross-platform issues |
+
+#### Infrastructure Agents
+
+| Agent | What It Searches For |
+|-------|---------------------|
+| `docker-infra` | Dockerfile issues, compose config, port security, healthchecks (run when scope includes `docker/`) |
+| `ci-workflows` | Missing timeouts, script injection, permissions gaps, silent failures (run when scope includes `.github/` or `ci`) |
+
+#### Documentation Agents (scope includes `docs/` or `site/`)
+
+| Agent | What It Searches For |
+|-------|---------------------|
+| `docs-consistency` | Broken links, outdated info, wrong commands, inconsistent terminology |
+| `landing-site` | SEO gaps, broken links, a11y issues, missing error pages |
+
+#### Cross-Cutting Agents (always included)
+
+| Agent | What It Searches For |
+|-------|---------------------|
+| `security-gaps` | Cross-stack security issues: SSRF, XSS, injection vectors, hardcoded secrets across all languages |
+| `dependency-issues` | Unused deps, missing deps, version conflicts across all package managers |
+| `docstring-gaps` | Public classes/functions missing Google-style docstrings |
+
+### Agent Prompt Template
+
+Every agent receives this structure:
+
+```text
+## Task
+You are searching the codebase for ONE specific type of issue: {ISSUE_TYPE}.
+
+## Architecture Context
+{ARCHITECTURE_BRIEF from Phase 1b}
+
+## Existing Open Issues (do NOT report these)
+{ISSUE_LIST from Phase 1a}
+
+## Scope
+Search: {SCOPE_DIRECTORIES}
+
+## Rules
+1. For each finding, report: file path, line number, what's wrong, operational impact
+2. Cross-reference against the existing issues list -- only report what's NOT already tracked
+3. BE SKEPTICAL of your own findings -- verify each one by reading the actual code
+4. If you find ZERO issues, state that clearly but also explain what you checked
+5. Do NOT flag things that are intentional design decisions (check comments, docstrings)
+6. Rate each finding: CONFIRMED (verified in code) or LIKELY (needs validation)
+
+## What to Search For
+{CATEGORY-SPECIFIC INSTRUCTIONS}
+```
+
+### Launch
+
+Launch ALL selected agents in parallel using the Agent tool with `run_in_background: true`. Give each a descriptive `name` for tracking.
+
+Track agent count and report to user: "Launched N audit agents in parallel. Waiting for results..."
+
+---
+
+## Phase 3: Collect & Deduplicate
+
+As agents complete, collect their findings. Once ALL agents have reported:
+
+### Step 3a: Check for suspicious clean results
+
+If any agent reported zero findings, flag it:
+- "Agent `{name}` found zero issues. This may be accurate or the agent may have been too shallow."
+- These categories are candidates for Phase 5 (deep dive).
+
+### Step 3b: Merge all findings into a single list
+
+Combine findings from all agents into one flat list with columns:
+- Source agent
+- File path : line number
+- Category
+- Description
+- Agent's self-assessed confidence (CONFIRMED / LIKELY)
+
+### Step 3c: Deduplicate
+
+- Multiple agents may flag the same line/issue (e.g., security + validation both flag missing input checks)
+- Merge duplicates, keep the most detailed description
+- Remove findings that match existing open GitHub issues (by file path + description similarity)
+
+---
+
+## Phase 4: Validate Findings
+
+**MANDATORY. Never skip this phase.**
+
+Launch validation agents in parallel. Each validation agent gets a batch of 8-12 findings and is instructed to:
+
+1. Read the actual source file at the reported line number
+2. Verify the issue exists as described
+3. Check if the "issue" is actually intentional (read comments, docstrings, related code)
+4. Check if CI/build/tests handle it in a way the audit agent missed
+5. Classify each finding:
+   - **CONFIRMED** -- verified in code, real issue
+   - **LIKELY CONFIRMED** -- code suggests the issue but edge case unclear
+   - **LIKELY FALSE** -- probably not a real issue (explain why)
+   - **FALSE POSITIVE** -- definitely not an issue (explain why)
+6. For intentional patterns (e.g., graceful shutdown error swallowing), mark as "CONFIRMED but INTENTIONAL" -- these are excluded from work packages
+
+### Validation Agent Prompt Template
+
+```text
+Validate these audit findings by reading the ACTUAL SOURCE CODE.
+For each finding, determine: CONFIRMED, LIKELY CONFIRMED, LIKELY FALSE, or FALSE POSITIVE.
+
+For each:
+1. Read the file at the reported line number
+2. Quote the actual code
+3. Check if it's intentional (read surrounding comments, docstrings)
+4. Check if CI, tests, or build pipelines handle it
+5. Give a clear verdict with evidence
+
+{BATCH OF FINDINGS}
+```
+
+### After validation
+
+- Remove all FALSE POSITIVE and LIKELY FALSE findings
+- Keep CONFIRMED and LIKELY CONFIRMED
+- Mark CONFIRMED-but-INTENTIONAL as excluded (note in report but don't create issues)
+- Calculate false positive rate: `removed / total`
+- Report: "Validated N findings. Removed M false positives (X%). N remaining confirmed findings."
+
+---
+
+## Phase 5: Deep Dive on Suspicious Clean Results
+
+For each audit category that found ZERO issues in Phase 2:
+
+1. **Research the relevant architecture first** -- read the actual implementation files to understand how the system works
+2. **Craft a targeted, informed prompt** -- include specific architectural details (e.g., "the observability stack uses structlog with 8 sinks routed by logger name prefix via _SINK_ROUTING in sinks.py")
+3. **Launch a second agent** with the enriched prompt and explicit instructions: "The first audit found nothing. Dig deeper. Check specific functions, look for subtle gaps, verify edge cases."
+4. **Validate any new findings** (same as Phase 4)
+5. Add validated findings to the main list
+
+Skip this phase if the user passed `--quick` or if the zero-finding categories are genuinely well-covered (e.g., dependencies audit finding nothing is believable).
+
+---
+
+## Phase 6: Present Validated Findings
+
+Present the validated, deduplicated findings to the user. Format:
+
+### Summary Table
+
+```text
+| # | Finding | File:Line | Category | Verdict |
+|---|---------|-----------|----------|---------|
+| 1 | Description | path:123 | category | CONFIRMED |
+| ... | ... | ... | ... | ... |
+```
+
+### Statistics
+
+- Total findings: N
+- False positives removed: M (X%)
+- Confirmed: N1, Likely confirmed: N2
+- Intentional (excluded): N3
+- Categories with zero findings: list
+
+### User Gate
+
+If `--report-only` was passed, skip this gate and go directly to the markdown report (option 3 below).
+
+Otherwise, ask the user:
+1. **"Proceed to group into work packages and create issues" (Recommended)**
+2. "Show me the full detail for each finding first"
+3. "Export as markdown report only (no issues)"
+
+---
+
+## Phase 7: Group into Work Packages
+
+**Group by code proximity, NOT by severity.**
+
+### Grouping Rules
+
+1. **Same directory/module** -- findings touching the same `src/synthorg/<module>/` go together
+2. **Same file** -- multiple findings in one file always go in the same package
+3. **Dependency chain** -- if fixing A requires fixing B first, bundle them
+4. **Same developer context** -- what would a developer naturally fix in one sitting?
+5. **Target medium scope** -- each package should be a meaningful PR, not too small (1 finding) or too large (15+ findings)
+6. **Never group by severity** -- a HIGH and LOW in the same file go together; a HIGH and HIGH in different modules do NOT
+
+### Common Groupings
+
+These patterns recur across audits:
+- **API controller sweep** -- validation, response patterns, auth hardening (all in `api/controllers/`)
+- **Observability fixes** -- sink routing, correlation, event constants (all in `observability/`)
+- **Test quality** -- flaky fixes + missing coverage (all in `tests/`)
+- **CI hardening** -- timeouts, permissions, script safety (all in `.github/`)
+- **Documentation** -- content fixes across `docs/` and `site/`
+- **Language-specific** -- Go fixes together, Vue fixes together
+
+### Standalone features
+
+If a finding is a "feature not yet implemented" (spec drift with TODO/stub), it can be its own issue if medium+ scope. Do NOT create meta/tracking issues -- each issue must be implementable on its own.
+
+### Present to User
+
+Show the proposed work packages:
+
+```text
+## Proposed Work Packages (N total)
+
+### WP1: Name
+| # | Finding |
+|---|---------|
+| 1 | ... |
+| 2 | ... |
+```
+
+**Rationale:** Why these go together.
+
+```text
+### WP2: Name
+...
+```
+
+Ask: "Create issues for all N work packages? Or adjust groupings first?"
+
+---
+
+## Phase 8: Final Issue Dedup & Creation
+
+### Step 8a: Final dedup against existing issues
+
+Before creating, do one final check:
+
+```bash
+gh issue list --repo OWNER/REPO --state open --limit 200 --json number,title,labels
+```
+
+For each work package, search for title/description overlap with existing issues. If a finding is already covered by an existing issue, either:
+- Remove it from the work package
+- Note "extends #NNN" in the new issue body
+
+### Step 8b: Create issues
+
+For each work package, create a GitHub issue with:
+
+- **Title**: `<type>: <concise description>` (matching commit convention: fix, feat, chore, docs, test)
+- **Body**:
+  - `## Summary` -- 1-2 sentences
+  - `## Findings` -- table of findings with file:line, description
+  - `## Files to Modify` -- list of files that need changes
+  - Design spec references if applicable
+- **Labels**: appropriate type/scope/spec labels
+
+Use the `mcp__github__issue_write` tool or `gh issue create` via Bash.
+
+**IMPORTANT**: Never use em-dashes or non-ASCII punctuation in issue bodies (project convention).
+
+### Step 8c: Report
+
+Present the complete list of created issues:
+
+```text
+| WP | Issue | Title |
+|----|-------|-------|
+| 1 | #NNN | ... |
+| ... | ... | ... |
+```
+
+---
+
+## Rules
+
+1. **NEVER present unvalidated findings to the user.** Validation (Phase 4) is mandatory.
+2. **ALWAYS research architecture before auditing.** Phase 1b is not optional.
+3. **Be skeptical of clean results.** Zero findings triggers Phase 5 deep dive.
+4. **Group by code proximity, NEVER by severity.** What files does a developer touch together?
+5. **No meta/tracking issues.** Every issue must be directly implementable.
+6. **Dedup twice.** Once in agent prompts (Phase 2), once before issue creation (Phase 8a).
+7. **All agents run in parallel.** Never launch agents sequentially when they're independent.
+8. **Agent prompts include architecture context.** Never launch a "blind" agent.
+9. **Intentional patterns are not bugs.** Graceful shutdown error swallowing, defensive cleanup, etc. are valid patterns -- exclude from issues but note in report.
+10. **Respect project conventions.** Read CLAUDE.md, use correct commands (`uv run python -m pytest`, not `uv run pytest`), no vendor names, etc.
+11. **Default to creating issues.** Unless user passes `--report-only`, the skill creates issues.
+12. **Never push code.** This skill audits and creates issues -- it does not fix code.