Claude-Code-Game-Studios/.claude/skills/soak-test/SKILL.md

---
name: soak-test
description: "Soak test protocol for extended play — what to observe and log for slow leaks, fatigue, late-appearing edge cases."
argument-hint: "[duration: 30m | 1h | 2h | 4h] [focus: memory | stability | balance | all]"
user-invocable: true
allowed-tools: Read, Glob, Grep, Write
model: sonnet
---

!`source "${CLAUDE_PROJECT_DIR:-.}/.claude/hooks/yaml-helper.sh" 2>/dev/null && resolve_config --keys automation`

**Automation mode**: Resolve `modes.automation` (`project.local.yaml` →
`project.yaml` → default `collaborative`). Every `AskUserQuestion` call and
every file write follows `.claude/docs/automation-modes.md`
(collaborative asks always · guided major-only · autonomous logs and proceeds;
`automation_always_ask` categories always prompt).

# Soak Test

A soak test (also called an endurance test) is an extended play session run
with specific observation goals. Unlike a smoke check (broad critical path,
~10 min) or a single-feature playtest (~30 min), a soak test runs for **30
minutes to several hours** to surface:

- **Memory leaks** — gradual heap growth that only appears after scene transitions
- **Performance drift** — frame time degradation that worsens over time
- **State accumulation bugs** — issues that only appear after N repetitions
  of a mechanic (inventory full, score overflow, AI state corruption)
- **Fun fatigue** — mechanics that feel good in a first session but grow
  repetitive over extended play
- **Content exhaustion** — the point where players run out of novel content

**This skill generates the observation protocol and analysis harness — the
human does the actual playing.**

**Output:** `production/qa/soak-test-[date]-[duration].md`

**When to run:**
- Polish phase — before `/gate-check release`
- After fixing a memory or stability issue (regression soak)
- When extended play has not been formally tracked

---

## 1. Parse Arguments

**Duration** (default: `1h`):
- `30m` — short soak; suitable for testing a single mechanic or scene
- `1h` — standard soak; covers most common leak categories
- `2h` — extended soak; recommended for first full Polish soak
- `4h` — deep soak; required for games with long session design (RPGs, sims)

**Focus** (default: `all`):
- `memory` — focus on heap size, object count, leak patterns
- `stability` — focus on crash/freeze/hang detection
- `balance` — focus on fun fatigue, content exhaustion, difficulty perception
- `all` — all of the above

---

## 2. Load Context

Read:
- `project.yaml` — `engine.name` (for engine-specific memory monitoring
  guidance) and `performance.*` budgets (memory ceiling, target FPS); for any
  key absent or empty (including when `project.yaml` has no `performance` or
  `engine` block), fall back to `.claude/docs/technical-preferences.md`
- `design/gdd/game-concept.md` — intended session length (for comparison against
  soak duration), core loop description
- Most recent file in `production/qa/playtests/` — prior playtest findings
  (to avoid re-documenting known issues)
- Most recent file in `production/qa/qa-plan-*.md` — current sprint test coverage
  (to understand what has been formally tested vs. what the soak covers)

Note any performance budget targets (`performance.*` from `project.yaml`, else `.claude/docs/technical-preferences.md`):
- Memory ceiling: [N MB, or "not set"]
- Target FPS: [N, or "not set"]
- Frame budget: [N ms, or "not set"]

---

## 3. Define Observation Checkpoints

Based on duration, generate timed checkpoints:

**30m soak**: T+0, T+10, T+20, T+30
**1h soak**: T+0, T+15, T+30, T+45, T+60
**2h soak**: T+0, T+20, T+40, T+60, T+80, T+100, T+120
**4h soak**: T+0, T+30, T+60, T+90, T+120, T+180, T+240

At each checkpoint, the observer records the observation items defined in
Phase 4.

---

## 4. Generate the Soak Test Protocol

### Memory / Stability observation items (if focus = memory or all)

Engine-specific monitoring guidance.

> **Record the unit the tool shows; never convert, and never assume one.**
> A soak test looks for **growth**, so every threshold below is a *ratio or a
> delta against this session's own T+0 baseline* — which is unit-agnostic and
> stays correct however the editor reports the number. Write the unit down at
> T+0 exactly as displayed and use it consistently for the rest of the run.
>
> This replaces a note asserting the return units of
> `Performance.get_monitor` — **NOT SOURCEABLE from `docs/engine-reference/`**,
> the identifier appears nowhere in it — a claim that sat one line under a row asking
> the tester to record "Static Memory (**KB**)". A wrong units claim in a leak
> detector is off by 1024× in the one measurement the protocol exists to take,
> and it would read as a plausible instruction throughout. Deltas need no such
> claim, so the safest fix was to stop needing it.

**Godot 4:**
- Open Debugger → Monitors tab; track `Memory → Static Memory` and
  `Object Count → Objects` across checkpoints
- Record: Static Memory (**unit as displayed**), Object Count, Orphan Nodes count
- Alert threshold: Memory growth > 20% from T+0 after the first 15 minutes
  (some growth on load is expected; sustained growth indicates a leak)
- **Orphan Nodes is the one absolute number worth watching**: it should return to
  its T+0 value after a scene unload. A ratio hides that; a non-zero floor that
  keeps rising is a leak regardless of units

**Unity:**
- Open Memory Profiler (Window → Analysis → Memory Profiler)
- Record: Total Reserved Memory, GC Allocated, Object Count at each checkpoint
  (**units as displayed**)
- Alert threshold: GC Allocated growing monotonically across 3+ checkpoints —
  a monotonicity check, deliberately unit-free

**Unreal Engine:**
- Use `stat memory` console command at each checkpoint
- Record: Physical Memory Used, Physical Memory Available (**units as displayed**)
- Alert threshold: Physical Memory Used growth **> 20% over the full soak**,
  measured against this run's T+0. The previous threshold was an absolute
  "> 50MB", which silently assumes both the unit *and* a project scale — 50MB is
  a rounding error for one game and a catastrophe for another

### Stability observation items (if focus = stability or all)

At each checkpoint, note:
- [ ] No crash, hang, or freeze occurred since last checkpoint
- [ ] Frame rate still within target budget ([target FPS] fps)
- [ ] Audio still playing correctly (no desync or silence)
- [ ] All HUD elements still rendering correctly
- [ ] Input responding as expected (no input loss or lag spike)

### Balance / fatigue observation items (if focus = balance or all)

Collect subjective observations at each checkpoint:
- [ ] Core mechanic still feels rewarding (Y/N)
- [ ] Perceived difficulty level: [too easy / appropriate / too hard]
- [ ] Any "I've seen this before" moments since last checkpoint? (novel content exhaustion)
- [ ] Any moment of frustration since last checkpoint? Note cause.
- [ ] Any moment of peak engagement since last checkpoint? Note cause.

---

## 5. Generate the Protocol Document

```markdown
# Soak Test Protocol

> **Date**: [date]
> **Duration**: [duration]
> **Focus**: [memory | stability | balance | all]
> **Engine**: [engine]
> **Generated by**: /soak-test

---

## Pre-Session Setup

Before starting the soak:

- [ ] Game is running from a **fresh launch** (not resumed from a prior session)
- [ ] All background applications closed (minimise OS memory interference)
- [ ] Performance monitoring tool open and recording:
  - **Godot**: Debugger → Monitors tab → Memory section visible
  - **Unity**: Memory Profiler window open
  - **Unreal**: `stat memory` ready in console
- [ ] Soak target confirmed: [session design intent from game concept]
- [ ] Prior known issues to watch for: [from most recent playtest / qa-plan]

---

## Baseline (T+0) — Record Before Playing

| Metric | Baseline Value |
|--------|---------------|
| Memory / Heap | [record before first frame of gameplay] |
| Object Count | [record] |
| FPS (first 30 seconds) | [record] |
| [Engine-specific metric] | [record] |

---

## Checkpoint Log

### T+[N] minutes

**Memory / Stability** *(if applicable)*:

| Metric | Value | Δ from Baseline | Alert? |
|--------|-------|-----------------|--------|
| Memory / Heap | | | |
| Object Count | | | |
| FPS | | | |
| Crashes / Hangs | | | |

**Stability checks**:
- [ ] No crash or hang since last checkpoint
- [ ] Frame rate within budget ([N] fps target)
- [ ] Audio correct
- [ ] HUD rendering correctly
- [ ] Input responding correctly

**Balance / Fatigue** *(if applicable)*:
- Core mechanic still rewarding: Y / N
- Difficulty perception: too easy / appropriate / too hard
- Notable moments: [note any peak engagement or frustration]
- Content exhaustion signs: Y / N — [describe]

**Free observations**:
*(Note anything unexpected observed since the last checkpoint)*

---

[Repeat Checkpoint Log section for each timed checkpoint]

---

## Post-Session Analysis

### Memory Trend

| Checkpoint | Memory | Δ/hr extrapolated |
|------------|--------|-------------------|
| T+0 | | |
| [T+N] | | |

**Leak detected?** Y / N
**Estimated time to OOM at current rate**: [N hours / not applicable]

### Stability Summary

Total crashes: [N]
Total hangs: [N]
Worst FPS observed: [N] fps at [checkpoint]
Performance degradation: stable / mild / severe

### Balance / Fatigue Summary

Fun curve: [engaged throughout / fatigue onset at T+N / repetitive from start]
Content exhaustion point: [never / at T+N / early]
Difficulty arc: [appropriate / too easy throughout / difficulty spike at T+N]

### Issues Found

| ID | Severity | Checkpoint | Description |
|----|----------|------------|-------------|
| SOAK-001 | S[1-4] | T+[N] | [description] |

---

## Verdict: PASS / PASS WITH CONCERNS / NOT ASSESSED / FAIL

**PASS**: No leaks detected, stability maintained, fun factor consistent
**PASS WITH CONCERNS**: Minor drift or fatigue noted; addressable in Polish
**NOT ASSESSED**: The soak did not run to a length that could show what it looks
for — say how far it got and which checkpoints were never reached
**FAIL**: Memory leak confirmed, stability breach, or severe fun fatigue

> **A short soak cannot return PASS.** Everything this protocol exists to detect
> — slow leaks, fatigue, late-appearing edge cases — is by definition invisible
> early, so a session that ended before the checkpoints it was built around has
> not shown stability; it has shown nothing yet. Record `NOT ASSESSED — reached
> T+[N] of [duration]; checkpoints [list] not reached`. Ranks **above both pass
> values** and **below FAIL**: a crash observed at T+20 is a real finding no
> matter how short the run, and must not be demoted behind the run's length.
> The same applies when the build crashed for reasons unrelated to the soak, when
> no memory instrumentation was available (nothing was measured, so "no leaks
> detected" means "no leaks could have been detected"), or when the protocol was
> written but never executed — a protocol document is not a result.

---

## Sign-Off

- **Tester**: [name] — [date]
- **QA Lead review**: [name] — [date]
```

---

## 6. Write Output

Present the protocol summary in conversation, then ask:

"May I write this soak test protocol to
`production/qa/soak-test-[date]-[duration].md`?"

Write only after approval.

After writing:

"Protocol written. To run the soak:
1. Open the file and follow the Pre-Session Setup checklist
2. Record each checkpoint as you play
3. Complete the Post-Session Analysis section when done
4. File bugs from 'Issues Found' to `production/qa/bugs/`
5. Run `/bug-triage sprint` after the session to integrate any S1/S2 issues

If the verdict is FAIL, run `/smoke-check` again after fixing the issues."

---

## Collaborative Protocol

- **This skill generates a protocol — humans run it** — never attempt to
  run a soak test automatically. The observations require a human observer.
- **Duration should match the game's session design** — a 5-minute game
  doesn't need a 4h soak; a city-builder might. Use judgment and ask if unclear.
- **First soak should be `all` focus** — narrow focus (memory-only) is for
  regression soaks after a specific fix, not the first pass
- **Ask before writing** — always confirm before creating the protocol file