Claude-Code-Game-Studios/.claude/docs/coding-standards.md

Coding Standards

• All game code must include doc comments on public APIs
• Architecture decisions are recorded as ADRs in docs/architecture/. How many is set by modes.workflow — all ADRs at full, critical ADRs only at standard, and none required at minimal, where the decision log and design/game-brief.md carry the rationale instead. See .claude/docs/workflow-modes.md.
• Gameplay values must be data-driven (external config), never hardcoded
• All public methods must be unit-testable (dependency injection over singletons)
• Commits must reference the relevant design document or task ID
• Commit messages: Use Conventional Commits format — feat:, fix:, chore:, docs:, test:, refactor:. Reference the story or task ID in the body (e.g., Story: EPIC-001-S02).
• Verification-driven development: Write tests first when adding gameplay systems. For UI changes, verify with screenshots. Compare expected output to actual output before marking work complete. Every implementation should have a way to prove it works.
• A parse check is not a run. Every story that changes something player-observable is launched and observed before it closes, and the observation is a retained screenshot in production/qa/evidence/. Procedure per engine: .claude/docs/run-and-observe.md. Not waived at qa.level: minimal — tests are, the look is not.

Design Document Standards

• All design docs use Markdown
• Each mechanic has a dedicated document in design/gdd/
• How many of the 8 sections are required depends on modes.workflow — all 8 at full, 5 (+ Formulas when the system defines numeric rules — rates, curves, thresholds, costs; the system's Category is a hint, not the test) at standard, and no GDD at all at minimal, where design/game-brief.md is the design record. See .claude/docs/workflow-modes.md. The 8 sections:
  1. Overview -- one-paragraph summary
  2. Player Fantasy -- intended feeling and experience
  3. Detailed Rules -- unambiguous mechanics
  4. Formulas -- all math defined with variables
  5. Edge Cases -- unusual situations handled
  6. Dependencies -- other systems listed
  7. Tuning Knobs -- configurable values identified
  8. Acceptance Criteria -- testable success conditions
• Balance values must link to their source formula or rationale

Testing Standards

Test Evidence by Story Type

All stories must have appropriate test evidence before they can be marked Done:

Story Type	Required Evidence	Location	Default Gate Level
Logic (formulas, AI, state machines)	Automated unit test — must pass	tests/unit/[system]/	BLOCKING
Integration (multi-system)	Integration test OR documented playtest	tests/integration/[system]/	BLOCKING
Visual/Feel (animation, VFX, feel)	Retained screenshot + lead sign-off	production/qa/evidence/	BLOCKING
UI (menus, HUD, screens)	Retained screenshot of each screen touched	production/qa/evidence/	BLOCKING
Config/Data (balance tuning)	Smoke check pass	production/qa/smoke-[date].md	ADVISORY

The Default Gate Level applies when testing.strict is not set in project.yaml. A project may override it per test type: testing.strict.logic, .integration, .visual, .ui, and .config each take true (BLOCKING) or false (ADVISORY). /story-done, /story-readiness, /dev-story, /gate-check, and /smoke-check resolve the effective level from that setting, falling back to the defaults above when it is absent.

Why Visual and UI block. "Retained" is load-bearing — the screenshot must still be on disk in production/qa/evidence/ when the story is closed. One that was captured and discarded is an assertion, not evidence. These two rows block because for a game the way it looks is the product: an advisory visual gate gets deferred in favour of whatever does block, and the result is a well-tested game that looks wrong.

Exception — /smoke-check. The ADVISORY default for Config/Data above applies to per-story evidence gates. /smoke-check is a build-health gate, not a per-story evidence gate, so its own unset default for testing.strict.config is BLOCKING. The two defaults differ on purpose.

Automated Test Rules

• Naming: per engine — .claude/rules/test-standards.md
• Determinism: Tests must produce the same result every run — no random seeds, no time-dependent assertions
• Isolation: Each test sets up and tears down its own state; tests must not depend on execution order
• No hardcoded data: Test fixtures use constant files or factory functions, not inline magic numbers (exception: boundary value tests where the exact number IS the point)
• Independence: Unit tests do not call external APIs, databases, or file I/O — use dependency injection

What NOT to Automate

• Visual fidelity (shader output, VFX appearance, animation curves)
• "Feel" qualities (input responsiveness, perceived weight, timing)
• Platform-specific rendering (test on target hardware, not headlessly)
• Full gameplay sessions (covered by playtesting, not automation)

CI/CD Rules

• Automated test suite runs on every push to main and every PR
• No merge if tests fail — tests are a blocking gate in CI
• Never disable or skip failing tests to make CI pass — fix the underlying issue
• Engine-specific CI commands:
  • Godot: godot --headless -s -d --remote-debug tcp://127.0.0.1:0 res://addons/gdUnit4/bin/GdUnitCmdTool.gd -a res://tests --ignoreHeadlessMode
  • Unity: game-ci/unity-test-runner@v4 (GitHub Actions)
  • Unreal: headless runner with -nullrhi flag