# Dev Test Gaps

> This skill should be used when validating test coverage against requirements, after implementation tasks complete (Phase 5.5 of /dev workflow). Invoked automatically by dev-implement before review phase.

- Skill: `majiayu000/dev-test-gaps` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds add majiayu000/dev-test-gaps`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/dev-test-gaps/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Productivity
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/majiayu000/dev-test-gaps

---


Announce: "Using dev-test-gaps (Phase 5.5) to validate test coverage against requirements."

**Load shared enforcement:**

Read `${CLAUDE_PLUGIN_ROOT}/references/dev-common-constraints.md`.

## Contents

- [The Iron Law of Test-Only](#the-iron-law-of-test-only)
- [Red Flags - STOP Immediately](#red-flags---stop-immediately)
- [The Process](#the-process)
- [Phase 1: Read Requirements and Plan](#phase-1-read-requirements-and-plan)
- [Phase 2: Scan Test Infrastructure](#phase-2-scan-test-infrastructure)
- [Phase 3: Map Coverage](#phase-3-map-coverage)
- [Phase 4: Classify Coverage](#phase-4-classify-coverage)
- [Phase 5: Fill Gaps](#phase-5-fill-gaps)
- [Phase 6: Produce VALIDATION.md](#phase-6-produce-validationmd)
- [Exit Criteria](#exit-criteria)

# Test Gap Validation

<EXTREMELY-IMPORTANT>
## The Iron Law of Test-Only

**NEVER MODIFY IMPLEMENTATION CODE. TESTS ONLY OR ESCALATE. This is not negotiable.**

Your job is to validate that tests exist for every requirement, and fill gaps by writing NEW tests. You do NOT fix bugs, refactor code, or touch implementation files.

| Allowed | NOT Allowed |
|---------|-------------|
| Read implementation code (for understanding) | Edit implementation code |
| Write new test files | Modify existing implementation files |
| Update existing test files (add cases) | "Quick fix" to make a test pass |
| Create test fixtures/helpers | Change production code to be "more testable" |
| Escalate implementation bugs | Silently work around implementation bugs |

**If a test fails because the implementation is wrong, ESCALATE. Do not fix the implementation.**
</EXTREMELY-IMPORTANT>

<EXTREMELY-IMPORTANT>
## Red Flags - STOP Immediately If You Catch Yourself Thinking:

| Thought | Why It's Wrong | Do Instead |
|---------|----------------|------------|
| "The implementation has a small bug, let me fix it" | You are a test auditor, not an implementer | Escalate: mark requirement as FAIL in VALIDATION.md |
| "This requirement doesn't need a test" | Every requirement needs coverage evidence | Write the test. If truly untestable, document why. |
| "The existing test sort of covers this" | "Sort of" = PARTIAL, not COVERED | Write the specific test or classify as PARTIAL |
| "I'll adjust the implementation to match the test" | Implementation is immutable to you | Write the test to match the spec, escalate if it fails |
| "This is a trivial requirement" | Trivial requirements have trivial tests. Write them. | Write the test anyway |
| "Tests are passing so coverage must be fine" | Passing tests prove what IS tested, not what ISN'T | Map every requirement explicitly |
| "I need to refactor the code to test it" | Refactoring = modifying implementation = violation | Escalate as "untestable without refactor" |
</EXTREMELY-IMPORTANT>

## The Process

```
1. READ requirements from .planning/SPEC.md
2. READ tasks from .planning/PLAN.md
3. SCAN test infrastructure (framework, config, patterns)
4. MAP each requirement → test coverage
5. CLASSIFY: COVERED / PARTIAL / MISSING
6. FILL gaps by spawning test-gap-auditor agent for MISSING requirements
7. PRODUCE .planning/VALIDATION.md with full coverage map
```

## Phase 1: Read Requirements and Plan

Read `.planning/SPEC.md` and extract every testable requirement:

```
For each requirement in SPEC.md:
  - Extract the requirement ID (e.g., AUTH-01, UI-02) from the Requirements table
  - Note the requirement description
  - Note the scope (v1/v2/out-of-scope) — only v1 requirements need coverage
  - Note the acceptance criteria from Success Criteria (mapped by ID)
```

Read `.planning/PLAN.md` and extract:
- Testing strategy (framework, commands)
- Task-to-requirement mapping
- Test file locations mentioned

**Output:** A list of requirements to validate, each with acceptance criteria.

## Phase 2: Scan Test Infrastructure

Detect the project's test setup:

```bash
# Detect test framework and config
ls package.json pyproject.toml Cargo.toml pixi.toml setup.cfg 2>/dev/null
```

Then read the relevant config to identify:
- **Framework:** pytest, jest, vitest, cargo test, etc.
- **Config file:** jest.config.*, pytest.ini, pyproject.toml [tool.pytest], etc.
- **Test directories:** tests/, __tests__/, spec/, test/
- **Run command:** npm test, pytest, cargo test, etc.
- **Existing test patterns:** How are tests structured? (describe/it, test functions, test classes)

```bash
# Find test files
fd -e test.ts -e test.js -e spec.ts -e spec.js -e _test.py -e _test.go -e _test.rs . 2>/dev/null || fd test . tests/ __tests__/ spec/ test/ 2>/dev/null | head -30
```

Read 2-3 existing test files to understand patterns (naming, imports, assertions, fixtures).

**Output:** Test infrastructure summary table.

## Phase 3: Map Coverage

For each requirement extracted in Phase 1:

1. **Search for test coverage:**
   - Grep test files for keywords from the requirement
   - Look for test names that reference the requirement
   - Check if acceptance criteria are asserted

2. **Read candidate test files** to confirm they actually exercise the requirement (not just mention it)

3. **Record the mapping:** requirement ID -> test file -> specific test(s)

## Phase 4: Classify Coverage

For each requirement, assign a classification:

| Classification | Criteria |
|---------------|----------|
| **COVERED** | Test exists, exercises the requirement, asserts correct behavior |
| **PARTIAL** | Test exists but: missing edge cases, incomplete assertions, or only tests happy path |
| **MISSING** | No test exercises this requirement |

### Classification Red Flags

These do NOT count as COVERED:

- Test file exists but test is `.skip()`'d or `@pytest.mark.skip`
- Test imports the module but never calls the function
- Test checks type/existence but not behavior
- Test only uses mocks (no integration with real code)
- Test name references requirement but assertions are trivial

## Phase 5: Fill Gaps

For each MISSING requirement, spawn a test-gap-auditor agent using `subagent_type="workflows:test-gap-auditor"`:

**Tool Restrictions:** The auditor can Write/Edit test files ONLY. It MUST NOT modify implementation source code. If it discovers an implementation bug, it escalates — it does not fix.

**Agent prompt template:**

```
You are a test auditor. Your ONLY job is to write tests.

REQUIREMENT: [requirement description from SPEC.md]
ACCEPTANCE CRITERIA: [from SPEC.md]
TEST FRAMEWORK: [detected framework]
TEST PATTERNS: [patterns from existing tests]
TEST DIRECTORY: [where tests live]

RULES:
1. Write a test that exercises this requirement
2. Follow the existing test patterns in the project
3. Run the test and confirm it passes
4. If the test FAILS because the implementation is buggy, DO NOT fix the implementation
   - Report the failure
   - Include the error output
   - Mark as FAIL (escalated)
5. You have max 3 debug iterations to get the test working
   - Iteration 1: Write and run test
   - Iteration 2: Fix test issues (imports, setup, fixtures)
   - Iteration 3: Final attempt
   - After 3 failures: report FAIL (escalated)

OUTPUT: Report back with:
- Test file path
- Test name(s)
- PASS or FAIL (escalated)
- If FAIL: error output and whether it's a test issue or implementation bug
```

### Auditor Constraints

<EXTREMELY-IMPORTANT>
**The test-gap-auditor agent MUST NOT modify implementation code.**

If the auditor reports that a test fails due to an implementation bug:
1. Record it as FAIL (escalated) in VALIDATION.md
2. Do NOT spawn another agent to fix it
3. Do NOT fix it yourself
4. The escalation will be addressed in the review phase

**Fixing implementation bugs is dev-implement's job, not dev-test-gaps'.**
</EXTREMELY-IMPORTANT>

### Auditor Iteration Rules

```
Attempt 1: Write test → Run
  PASS → Done (record as gap filled)
  FAIL (test bug) → Fix test → Attempt 2
  FAIL (impl bug) → Escalate immediately

Attempt 2: Fixed test → Run
  PASS → Done (record as gap filled)
  FAIL (test bug) → Fix test → Attempt 3
  FAIL (impl bug) → Escalate immediately

Attempt 3: Fixed test → Run
  PASS → Done (record as gap filled)
  FAIL → Escalate (max iterations)
```

## Phase 6: Produce VALIDATION.md

After all requirements are mapped and gaps addressed, create `.planning/VALIDATION.md`:

```markdown
---
status: [draft | validated | gaps_found]
coverage: [N/M requirements covered]
---
# Test Coverage Validation

## Test Infrastructure
| Property | Value |
|----------|-------|
| Framework | [detected] |
| Config | [path] |
| Run command | [command] |

## Coverage Map
| Req ID | Requirement | Test File | Status | Notes |
|--------|-------------|-----------|--------|-------|
| CAT-01 | [description] | [test path] | COVERED/PARTIAL/MISSING | [details] |

## Gaps Filled
| Req ID | Requirement | Test File | Result |
|--------|-------------|-----------|--------|
| CAT-01 | [description] | [new test path] | PASS/FAIL (escalated) |

## Summary
- Requirements: N total
- Covered: X
- Partial: Y
- Missing: Z (W filled, V escalated)
```

### Status Rules

| Condition | Status |
|-----------|--------|
| All requirements COVERED, no escalations | `validated` |
| All requirements COVERED after gap-filling, no escalations | `validated` |
| Any PARTIAL or MISSING remain, or any escalations | `gaps_found` |
| Validation in progress | `draft` |

## Exit Criteria

**Checkpoint type:** human-verify (VALIDATION.md status is machine-verifiable)

**Validation passes (proceed to review):**
- `.planning/VALIDATION.md` exists with status `validated`
- All requirements classified as COVERED
- All gap-filling tests pass
- No escalations

**Validation fails (gaps found):**
- `.planning/VALIDATION.md` exists with status `gaps_found`
- Report to dev-implement orchestrator:
  - Which requirements have gaps
  - Which tests failed due to implementation bugs (escalations)
  - Recommendation: re-run specific implementation tasks or escalate to user

## Run Final Test Suite

Before setting status to `validated`, run the FULL test suite one final time:

```bash
# Run whatever test command was detected in Phase 2
[detected test command]
```

- ALL tests must pass (including newly written ones)
- If any test fails, investigate: is it a test issue or implementation bug?
- Test issues: fix the test (within the 3-iteration limit)
- Implementation bugs: escalate

**Only set status to `validated` after the full suite passes.**

## Drive-Aligned Framing

<EXTREMELY-IMPORTANT>
**Skipping test gap validation is NOT HELPFUL -- you're shipping code with unknown coverage holes the user will discover in production.**

| Your Drive | Why You Skip | What Actually Happens | The Drive You Failed |
|------------|-------------|----------------------|---------------------|
| **Helpfulness** | "Tests passed, coverage must be fine" | Passing tests prove what IS tested, not what ISN'T. User finds untested bugs. | **Anti-helpful** |
| **Competence** | "I wrote good tests during implementation" | Good tests per task != full requirement coverage. Gaps hide between tasks. | **Incompetent** |
| **Efficiency** | "Validation is redundant after TDD" | TDD ensures task-level coverage. Test gap validation ensures requirement-level coverage. Different. | **Inefficient** |

**The protocol is not overhead you pay. It is the safety net you provide.**
</EXTREMELY-IMPORTANT>