Cover

---
name: cover
license: MIT
compatibility: "Claude Code 2.1.251+. Requires network access."
description: "Generate tests that do not exist yet. Analyzes coverage gaps, then writes and runs new test files across three tiers (unit, integration via testcontainers, Playwright E2E), one test-generator agent per tier, healing failures for up to 3 iterations. Use when code has no tests or when raising coverage after implementation. Do NOT use to grade tests that already exist (use /ork:verify) or to run a suite without writing anything new."
argument-hint: "[scope-or-feature]"
context: fork
# user-typed commands stay interactive; CC >= 2.1.218 backgrounds forks by default (#3093)
background: false
version: 1.2.0
author: OrchestKit
tags: [testing, coverage, unit, integration, e2e, test-generation, real-services, testcontainers]
user-invocable: true
allowed-tools: [SendMessage, AskUserQuestion, Bash, Read, Write, Edit, Grep, Glob, Agent, TaskCreate, TaskUpdate, TaskList, TaskStop, ToolSearch, Workflow, CronCreate, CronDelete, Monitor, PushNotification, mcp__memory__search_nodes, mcp__context7__resolve-library-id, mcp__context7__query-docs]
skills: [testing-unit, testing-integration, testing-e2e, testing-perf, testing-llm, chain-patterns, memory, quality-gates]
complexity: high
persuasion-type: discipline
effort: high
model: sonnet
hooks:
  PreToolUse:
    - matcher: "Bash"
      command: "${CLAUDE_PLUGIN_ROOT}/hooks/bin/run-hook.mjs skill/test-framework-detector"
      once: true
metadata:
  category: workflow-automation
  mcp-server: memory, context7
triggers:
  keywords: [cover, "generate tests", "test suite", "test coverage", "write tests for", "add tests", "need tests"]
  examples:
    - "generate tests for the authentication service"
    - "cover the payment module with unit and integration tests"
    - "I just finished implementing checkout, now write tests"
  anti-triggers: [verify, run tests, npm test, fix, implement, review]
paths: ["src/**/*.test.{ts,tsx,js}", "**/.coveragerc", "vitest.config.*", "jest.config.*"]
invocation_hooks:
  - "command -v vitest >/dev/null 2>&1 || command -v jest >/dev/null 2>&1 || echo 'Warning: no test runner found — run npm install first'"
---

# Cover — Test Suite Generator

Generate comprehensive test suites for existing code with real-service integration testing and automated failure healing.

> **Note:** If `disableSkillShellExecution` is enabled (CC 2.1.91), the precondition check for vitest/jest won't run. Verify a test runner is installed before proceeding: `npx vitest --version` or `npx jest --version`.

## Quick Start

```bash
/ork:cover authentication flow
/ork:cover --model=opus payment processing
/ork:cover --tier=unit,integration user service
/ork:cover --real-services checkout pipeline
```

## Argument Resolution

```python
SCOPE = "$ARGUMENTS"  # e.g., "authentication flow"

# Flag parsing
MODEL_OVERRIDE = None
TIERS = ["unit", "integration", "e2e"]  # default: all three
REAL_SERVICES = False

for token in "$ARGUMENTS".split():
    if token.startswith("--model="):
        MODEL_OVERRIDE = token.split("=", 1)[1]
        SCOPE = SCOPE.replace(token, "").strip()
    elif token.startswith("--tier="):
        TIERS = token.split("=", 1)[1].split(",")
        SCOPE = SCOPE.replace(token, "").strip()
    elif token == "--real-services":
        REAL_SERVICES = True
        SCOPE = SCOPE.replace(token, "").strip()
```

---

## Step -0.5: Effort-Aware Coverage Scaling (CC 2.1.76, env var since 2.1.120)

Read `$CLAUDE_EFFORT` (CC 2.1.120+) first; explicit `--effort=` token wins as override. Default `high` when CC < 2.1.120 and no flag. Pattern matches assess + explore (#1540). Scale test generation depth:

| Effort Level | Tiers Generated | Agents | `maxIterations` to pass Phase 5 |
|-------------|----------------|--------|-----------------|
| **low** | Unit only | 1 agent | 2 (1 repair + 1 verify) |
| **medium** | Unit + Integration | 2 agents | 2 (1 repair + 1 verify) |
| **high** (default) | Unit + Integration + E2E | 3 agents | 3 (2 repairs + 1 verify) |
| **xhigh** (Opus 4.8, CC 2.1.111+) | Unit + Integration + E2E | 3 agents | 3 (the ceiling; xhigh adds agents, not heal passes) |

Values are what you pass as `maxIterations` in Phase 5. The script clamps to `[2, 3]`
(`heal-loop.js`), so anything outside that range is coerced, and the final iteration always
verifies rather than repairing. There is no 4-iteration mode.

> **Override:** Explicit `--tier=` flag or user selection overrides `/effort` downscaling.

## Step -1: MCP Probe + Resume Check

```python
# Probe MCPs (parallel):
# memory is alwaysLoad in .mcp.json (CC 2.1.121+, #1541) — probe below kept as fallback for older CC:
ToolSearch(query="select:mcp__memory__search_nodes")
ToolSearch(query="select:mcp__context7__resolve-library-id")

Write(".claude/chain/capabilities.json", {
  "memory": <true if found>,
  "context7": <true if found>,
  "skill": "cover",
  "timestamp": now()
})

# Resume check:
Read(".claude/chain/state.json")
# If exists and skill == "cover": resume from current_phase
# Otherwise: initialize state
```

---

## Step 0: Scope & Tier Selection

```python
AskUserQuestion(
  questions=[
    {
      "question": "What test tiers should I generate?",
      "header": "Test Tiers",
      "options": [
        {"label": "Full coverage (Recommended)", "description": "Unit + Integration (real services) + E2E"},
        {"label": "Unit + Integration", "description": "Skip E2E, focus on logic and service boundaries"},
        {"label": "Unit only", "description": "Fast isolated tests for business logic"},
        {"label": "E2E only", "description": "Playwright browser tests"}
      ],
      "multiSelect": false
    },
    {
      "question": "Healing strategy for failing tests?",
      "header": "Failure Handling",
      "options": [
        {"label": "Auto-heal (Recommended)", "description": "Fix failing tests up to 3 iterations"},
        {"label": "Generate only", "description": "Write tests, report failures, don't fix"},
        {"label": "Strict", "description": "All tests must pass or abort"}
      ],
      "multiSelect": false
    }
  ]
)
```

Override TIERS based on selection. Skip this step if `--tier=` flag was provided.

---

## Task Management (MANDATORY)

```python
# 1. Create main task IMMEDIATELY
TaskCreate(subject=f"Cover: {SCOPE}", description="Generate comprehensive test suite with real-service testing", activeForm=f"Generating tests for {SCOPE}")

# 2. Create subtasks for each phase
TaskCreate(subject="Discover scope and detect frameworks", activeForm="Discovering test scope")    # id=2
TaskCreate(subject="Analyze coverage gaps", activeForm="Analyzing coverage gaps")                  # id=3
TaskCreate(subject="Generate tests (parallel per tier)", activeForm="Generating tests")            # id=4
TaskCreate(subject="Execute generated tests", activeForm="Running tests")                          # id=5
TaskCreate(subject="Heal failing tests", activeForm="Healing test failures")                       # id=6
TaskCreate(subject="Generate coverage report", activeForm="Generating report")                     # id=7

# 3. Set dependencies for sequential phases
TaskUpdate(taskId="3", addBlockedBy=["2"])  # Analysis needs discovery first
TaskUpdate(taskId="4", addBlockedBy=["3"])  # Generation needs gap map
TaskUpdate(taskId="5", addBlockedBy=["4"])  # Execution needs generated tests
TaskUpdate(taskId="6", addBlockedBy=["5"])  # Healing needs test results
TaskUpdate(taskId="7", addBlockedBy=["6"])  # Report needs healed suite

# 4. Update status as you progress
TaskUpdate(taskId="2", status="in_progress")  # When starting
TaskUpdate(taskId="2", status="completed")    # When done — repeat for each subtask
```

---

## 6-Phase Workflow

| Phase | Activities | Output |
|-------|------------|--------|
| **1. Discovery** | Detect frameworks, scan scope, find untested code | Framework map, file list |
| **2. Coverage Analysis** | Run existing tests, map gaps per tier | Coverage baseline, gap map |
| **3. Generation** | Parallel test-generator agents per tier | Test files created |
| **4. Execution** | Run all generated tests | Pass/fail results |
| **5. Heal** | Fix failures, re-run (max 3 iterations) | Green test suite |
| **6. Report** | Coverage delta, test count, summary | Coverage report |

### Phase Handoffs

| After Phase | Handoff File | Key Outputs |
|-------------|-------------|-------------|
| 1. Discovery | `01-cover-discovery.json` | Frameworks, scope files, tier plan |
| 2. Analysis | `02-cover-analysis.json` | Baseline coverage, gap map |
| 3. Generation | `03-cover-generation.json` | Files created, test count per tier |
| 5. Heal | `05-cover-healed.json` | Final pass/fail, iterations used |

---

### Phase 1: Discovery

Detect the project's test infrastructure and scope the work.

```python
# PARALLEL — all in ONE message:
# 1. Framework detection (hook handles this, but also scan manually)
Grep(pattern="vitest|jest|mocha|playwright|cypress", glob="package.json", output_mode="content")
Grep(pattern="pytest|unittest|hypothesis", glob="pyproject.toml", output_mode="content")
Grep(pattern="pytest|unittest|hypothesis", glob="requirements*.txt", output_mode="content")

# 2. Real-service infrastructure
Glob(pattern="**/docker-compose*.yml")
Glob(pattern="**/testcontainers*")
Grep(pattern="testcontainers", glob="**/package.json", output_mode="content")
Grep(pattern="testcontainers", glob="**/requirements*.txt", output_mode="content")

# 3. Existing test structure
Glob(pattern="**/tests/**/*.test.*")
Glob(pattern="**/tests/**/*.spec.*")
Glob(pattern="**/__tests__/**/*")
Glob(pattern="**/test_*.py")

# 4. Scope files (what to test)
# If SCOPE specified, find matching source files
Grep(pattern=SCOPE, output_mode="files_with_matches")
```

**Real-service decision:**
- `docker-compose*.yml` found → integration tests use real services
- `testcontainers` in deps → use testcontainers for isolated service instances
- Neither found + `--real-services` flag → error: "No docker-compose or testcontainers found. Install testcontainers or remove --real-services flag."
- Neither found, no flag → integration tests use mocks (MSW/VCR)

Load real-service detection details: `Read("${CLAUDE_PLUGIN_ROOT}/skills/cover/references/real-service-detection.md")`

### Phase 2: Coverage Analysis

Run existing tests and identify gaps.

```python
# Detect and run coverage command
# TypeScript: npx vitest run --coverage --reporter=json
# Python: pytest --cov=<scope> --cov-report=json
# Go: go test -coverprofile=coverage.out ./...

# Parse coverage output to identify:
# 1. Files with 0% coverage (priority targets)
# 2. Files below threshold (default 70%)
# 3. Uncovered functions/methods
# 4. Untested edge cases (error paths, boundary conditions)
```

Output coverage baseline to user immediately (progressive output).

### Phase 3: Generation (Parallel Agents)

Spawn test-generator agents per tier. Launch ALL in ONE message with `run_in_background=true`.

> **Isolation:** spawn each tier agent with `Agent(isolation="worktree")`, one
> worktree per tier (unit / integration / e2e) so they don't conflict. The
> subagent bypass of the worktree-isolation guard was fixed in CC 2.1.154 and
> completed in 2.1.203; ork's floor is >= 2.1.220, so every supported session
> gets real isolation. Do not create worktrees by hand before spawning.
>
> The new branch's base comes from the `worktree.baseRef` setting, never from a
> hardcoded branch name. **ork does not set it** — a plugin cannot, and no ork
> settings file carries it. Unless the operator put `"baseRef": "head"` in
> `.claude/settings.json` or `~/.claude/settings.json`, CC's default `"fresh"`
> applies: every tier agent branches from `origin/<default>`, unpushed local
> commits are invisible to it, and `tsc` fails with "cannot find module" for
> code you just wrote. Verify the setting before spawning. Full pattern:
> `Read("${CLAUDE_PLUGIN_ROOT}/skills/chain-patterns/references/worktree-agent-pattern.md")`

```python
# Unit tests agent (worktree-isolated)
if "unit" in TIERS:
    Agent(
        subagent_type="ork:test-generator",
        isolation="worktree",
        prompt=f"""Generate unit tests for: {SCOPE}
        Coverage gaps: {gap_map.unit_gaps}
        Framework: {detected_framework}
        Existing tests: {existing_test_files}

        Focus on:
        - AAA pattern (Arrange-Act-Assert)
        - Parametrized tests for multiple inputs
        - MSW/VCR for HTTP mocking (never mock fetch directly)
        - Factory-based test data (FactoryBoy/faker-js)
        - Edge cases: empty input, errors, timeouts, boundary values
        - Target: 90%+ business logic coverage""",
        run_in_background=True,
        max_turns=50,
        model=MODEL_OVERRIDE
    )

# Integration + E2E agents follow the same pattern:
# - subagent_type="ork:test-generator", isolation="worktree", run_in_background=True
# - Integration focus: API endpoints (Supertest/httpx), real DB, contract tests (Pact), Zod schema validation
# - E2E focus: Playwright, semantic locators, Page Object Model, axe-core a11y, visual regression
#
# Special case — emulate (Vercel Labs stateful API emulation):
# When integration tests need GitHub/Stripe/Resend/Okta/etc. emulated
# (HMAC webhooks, parallel port isolation, full config from scratch),
# spawn emulate-engineer instead of test-generator for that tier:
# - subagent_type="ork:emulate-engineer" (same isolation="worktree" form)
# - Pairs with emulate-seed skill for seed YAML patterns
```

Output each agent's results **as soon as it returns** — don't wait for all agents.

> **Focus mode (CC 2.1.101):** In focus mode, include the full coverage report (before/after delta, test count per tier, files created) in your final message.

### Phase 4: Execution

Run all generated tests and collect results.

```python
# Run test commands per tier (PARALLEL if independent):
# Unit: npx vitest run tests/unit/ OR pytest tests/unit/
# Integration: npx vitest run tests/integration/ OR pytest tests/integration/
# E2E: npx playwright test

# Collect: pass count, fail count, error details, coverage delta
```

### Phase 5: Heal Loop

Do NOT hand-roll the loop. Run the real executor:

```python
Workflow(
  scriptPath="${CLAUDE_PLUGIN_ROOT}/skills/cover/workflows/heal-loop.js",
  args={"testCommand": "<tier test command>", "tier": "unit", "testGlob": "tests/unit/",
        "maxIterations": 3}   # from the effort table above; omitted defaults to 3
)
# One invocation per tier that has failures.
```

**The iteration bound is enforced by the script, not by instruction.** `heal-loop.js`
runs a real counted loop clamped to `[2, 3]`: each iteration spawns a diagnose agent that
actually executes the test command and returns structured pass/fail plus the verbatim
failure output, then a repair agent that receives *that failure text* and edits test files
only. It exits early the moment the suite is green.

The **final iteration diagnoses but does not repair** - there would be no run left to verify
that repair. So `maxIterations: N` means N diagnose runs and N-1 repair passes, and the
default 3 means 2 repairs. A ceiling of 1 is coerced to 2, since 1 would mean zero repairs.

Every failure is classified into the taxonomy (`assertion`, `import`, `setup`, `timeout`,
`stale-selector`, `type`, `flaky`, plus `source-bug`), which selects the fix strategy.

The workflow returns `status: "healed"` or a **structured failure** (`status: "failed"`,
`healed: false`) carrying `remaining_failures`, `failure_categories`, and the per-iteration
ledger. Never report a `"failed"` result as a success: surface the still-failing tests in
the Phase 6 report.

Strategy detail (taxonomy table, fix rules, flaky prevention): `Read("${CLAUDE_PLUGIN_ROOT}/skills/cover/references/heal-loop-strategy.md")`

**Boundary: heal fixes TESTS, not source code.** If a test fails because the source code has a bug, report it — don't silently fix production code.

### Phase 6: Report

Generate coverage report with before/after comparison.

Full report layout (baseline→after table, tests-generated counts, heal iterations, files created, remaining gaps, next-steps commands): `Read("${CLAUDE_PLUGIN_ROOT}/skills/cover/references/coverage-report-template.md")`.

### PushNotification on Completion (CC 2.1.110+)

Full `/ork:cover` runs (unit + integration + E2E with heal loop) take 15–45 min. After the Phase 6 report is assembled, call `PushNotification(message=f"ork:cover complete — {SCOPE}: {coverage_pct}% coverage · {tests_generated} tests · {heal_loops} heal iters", status="proactive")`. Full rule: `Read("${CLAUDE_PLUGIN_ROOT}/skills/chain-patterns/rules/push-notification-on-completion.md")`.

### Coverage Drift Monitor (CC 2.1.71)

Optionally schedule weekly coverage drift detection:

```python
# Guard: Skip cron in headless/CI (CLAUDE_CODE_DISABLE_CRON)
# if env CLAUDE_CODE_DISABLE_CRON is set, run a single check instead
CronCreate(
  schedule="0 2 * * 0",
  prompt="Weekly coverage drift check for {SCOPE}: npm test -- --coverage.
    If coverage >= baseline → CronDelete.
    If coverage drops > 5% → alert with regression details and recommendation."
)
```

---

## Key Principles

- **Output limits (CC 2.1.77+):** Opus 4.8 defaults to 64k output tokens (128k upper bound). For large test suites, chunk generation across multiple agent turns if output approaches the limit.
- **Partial reads (CC 2.1.144+):** Read returns a `[PARTIAL view]` first page (not an error) on oversized files — re-read with explicit `offset`/`limit` so coverage analysis sees the whole file.
- **Tests only** — never modify production source code, only generate test files
- **Real services when available** — prefer testcontainers/docker-compose over mocks for integration tests because mock/prod divergence causes silent failures in production
- **Parallel generation** — spawn one test-generator agent per tier in ONE message
- **Heal, don't loop forever** — max 3 iterations, then report remaining failures
- **Progressive output** — show results as each agent completes
- **Factory over fixtures** — use FactoryBoy/faker-js for test data, not hardcoded values
- **Mock at network level** — MSW/VCR, never mock fetch/axios directly

---

## Agent Coordination

### Context Passing

Each test-generator agent receives: coverage gaps for its tier, test framework config, real-service infrastructure (testcontainers, docker-compose), and fixture patterns from the project.

### Monitor + Partial Results (CC 2.1.98)

Use `Monitor` for streaming test execution output from background agents:

```python
# Stream test suite output in real-time
Bash(command="npm test -- --coverage 2>&1", run_in_background=true)
Monitor(pid=test_task_id)  # Each line → notification
```

Full pattern reference (until-condition gates, partial-result salvage, `TaskOutput` vs `Monitor` decision): `Read("${CLAUDE_PLUGIN_ROOT}/skills/chain-patterns/references/monitor-patterns.md")`.

**Partial results (CC 2.1.98):** If a test-generator crashes mid-generation, synthesize what it produced:

```python
for agent_result in test_gen_results:
    if "[PARTIAL RESULT]" in agent_result.output: A `maxTurns` stop is also partial since CC 2.1.246 (summary: "stopped at its N-turn limit (partial result; continue it with SendMessage to the task-id)"); continue that agent with `SendMessage` instead of re-spawning it.
        # Agent crashed — check if it wrote any test files before dying
        partial_tests = Glob(pattern="**/tests/**/*.test.*", path=agent_result.worktree)
        if partial_tests:
            # 6 passing tests from a crashed agent > 0 tests
            # Copy partial tests to main worktree, run them in Phase 4
            for test_file in partial_tests:
                Bash(command=f"cp {test_file} {main_worktree}/{test_file}")
            # Flag as partial in report
```

### SendMessage (Test Healing)

> **Cross-session replies land in the parent (CC 2.1.248):** when a subagent sends `SendMessage` to another session, the reply is delivered to the parent session's conversation, never to the subagent; a subagent sends and moves on, the parent reads the answer. Cross-session `SendMessage` / `ListAgents` also work on Bedrock, Vertex and Foundry and with telemetry disabled (CC 2.1.248).

When a generated test fails, the healer agent can request context from the generator:

```python
SendMessage(to="test-generator-unit", message="Test user_service_test.py:42 fails — TypeError on mock return. What's the expected shape?")
```

### Skill Chain

Standard chain: `implement → cover → verify → commit`. Use `addBlockedBy` between each.

### Verification Gate

Before claiming coverage is complete, apply: `Read("${CLAUDE_PLUGIN_ROOT}/shared/rules/verification-gate.md")`. Run the coverage report fresh. "Should pass" is not evidence.

### Agent Status Protocol

All test-generator agents report using: `Read("${CLAUDE_PLUGIN_ROOT}/shared/status-protocol.md")`. BLOCKED if tests can't be written due to missing interfaces. NEEDS_CONTEXT if test expectations are unclear.

## Quality Bar

Done means all of these hold:
- coverage report shows the before→after delta from the actual coverage command output, not an estimate
- every generated test file was executed; final pass/fail counts pasted from the runner
- no production source modified — only test files created; a source bug is reported, never silently patched
- failures healed within the iteration budget (≤3, effort-scaled) or reported explicitly with the remaining-failure count
- each requested tier (unit/integration/e2e) either produced tests or has a stated reason it was skipped

## Related Skills

- `ork:implement` — generates tests during implementation (Phase 5); use `/ork:cover` after for deeper coverage
- `ork:verify` — grades existing tests 0-10; chain: `implement → cover → verify`
- `testing-unit` / `testing-integration` / `testing-e2e` — knowledge skills loaded by test-generator agents
- `ork:commit` — commit generated test files

> **Session recovery (CC 2.1.108+):** After idle periods or interruptions, use `/recap` to restore conversational context alongside checkpoint-resume state. Enabled by default since CC 2.1.110 (even with telemetry disabled).

## References

Load on demand with `Read("${CLAUDE_PLUGIN_ROOT}/skills/cover/references/<file>")`:

| File | Content |
|------|---------|
| `real-service-detection.md` | Docker-compose/testcontainers detection, service startup, teardown |
| `heal-loop-strategy.md` | Failure classification, fix patterns, iteration budget |
| `coverage-report-template.md` | Report format, delta calculation, gap analysis |
| `workflows/heal-loop.js` | Phase 5 executor — script-enforced 3-iteration repair loop (run via the Workflow tool) |

---

**Version:** 1.2.0 (April 2026) — `$CLAUDE_EFFORT` env var as primary effort signal (CC 2.1.120, #1540)