Validate readiness to advance between development phases. Produces a PASS/CONCERNS/FAIL verdict with specific blockers and required artifacts. Use when user says 'are we ready to move to X', 'can we advance to production', 'check if we can start the next phase', 'pass the gate'.
Installation
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Validate readiness to advance between development phases. Produces a PASS/CONCERNS/FAIL verdict with specific blockers and required artifacts. Use when user says 'are we ready to move to X', 'can we advance to production', 'check if we can start the next phase', 'pass the gate'.
This skill validates whether the project is ready to advance to the next development
phase. It checks for required artifacts, quality standards, and blockers.
Distinct from /project-stage-detect: That skill is diagnostic ("where are we?").
This skill is prescriptive ("are we ready to advance?" with a formal verdict).
Production — Feature development (Epic/Feature/Task tracking active)
Polish — Performance, playtesting, bug fixing
Release — Launch prep, certification
When a gate passes, write the new stage name to production/stage.txt
(single line, e.g. Production). This updates the status line immediately.
1. Parse Arguments
Target phase:$ARGUMENTS[0] (blank = auto-detect current stage, then validate next transition)
Also resolve the review mode (once, store for all gate spawns this run):
If --review [full|lean|solo] was passed → use that
Else read production/review-mode.txt → use that value
Else → default to lean
Note: in solo mode, director spawns (CD-PHASE-GATE, TD-PHASE-GATE, PR-PHASE-GATE, AD-PHASE-GATE) are skipped — gate-check becomes artifact-existence checks only. In lean mode, all four directors still run (phase gates are the purpose of lean mode).
With argument: /gate-check production — validate readiness for that specific phase
No argument: Auto-detect current stage using the same heuristics as
/project-stage-detect, then confirm with the user before running:
Use AskUserQuestion:
Prompt: "Detected stage: [current stage]. Running gate for [Current] → [Next] transition. Is this correct?"
Options:
[A] Yes — run this gate
[B] No — pick a different gate (if selected, show a second widget listing all gate options: Concept → Systems Design, Systems Design → Technical Setup, Technical Setup → Pre-Production, Pre-Production → Production, Production → Polish, Polish → Release)
Do not skip this confirmation step when no argument is provided.
2. Phase Gate Definitions
Gate: Concept → Systems Design
Required Artifacts:
design/gdd/game-concept.md exists and has content
Game pillars defined (in concept doc or design/gdd/game-pillars.md)
Concept prototype exists in prototypes/ with a REPORT.md showing PROCEED verdict
(/prototype [core-mechanic]) — skipping this means GDDs may be written for an
idea that hasn't been played. Acceptable if the concept is proven by other means.
Quality Checks:
Game concept has been reviewed (/design-review verdict not MAJOR REVISION NEEDED)
Core loop is described and understood
Target audience is identified
Visual Identity Anchor contains a one-line visual rule and at least 2 supporting visual principles
Gate: Systems Design → Technical Setup
Required Artifacts:
Systems index exists at design/gdd/systems-index.md with at least MVP systems enumerated
All MVP-tier GDDs exist in design/gdd/ and individually pass /design-review
A cross-GDD review report exists in design/gdd/ (from /review-all-gdds)
Quality Checks:
All MVP GDDs pass individual design review (8 required sections, no MAJOR REVISION NEEDED verdict)
/review-all-gdds verdict is not FAIL (cross-GDD consistency and design theory checks pass)
All cross-GDD consistency issues flagged by /review-all-gdds are resolved or explicitly accepted
System dependencies are mapped in the systems index and are bidirectionally consistent
MVP priority tier is defined
No stale GDD references flagged (older GDDs updated to reflect decisions made in later GDDs)
Gate: Technical Setup → Pre-Production
Required Artifacts:
Engine chosen (CLAUDE.md Technology Stack is not [CHOOSE])
Art bible exists at design/art/art-bible.md with at least Sections 1–4 (Visual Identity Foundation)
At least 3 Architecture Decision Records in docs/architecture/ covering
Foundation-layer systems (scene management, event architecture, save/load)
Engine reference docs exist in docs/engine-reference/[engine]/
Test framework initialized: tests/unit/ and tests/integration/ directories exist
CI/CD test workflow exists at .github/workflows/tests.yml (or equivalent)
At least one example test file exists to confirm the framework is functional
Master architecture document exists at docs/architecture/architecture.md
Architecture traceability index exists at docs/architecture/requirements-traceability.md
/architecture-review has been run (a review report file exists in docs/architecture/)
design/accessibility-requirements.md exists with accessibility tier committed
design/ux/interaction-patterns.md exists (pattern library initialized, even if minimal)
Quality Checks:
Architecture decisions cover core systems (rendering, input, state management)
Technical preferences have naming conventions and performance budgets set
Accessibility tier is defined and documented (even "Basic" is acceptable — undefined is not)
At least one screen's UX spec started (often the main menu or core HUD is designed during Technical Setup)
All ADRs have an Engine Compatibility section with engine version stamped
All ADRs have a GDD Requirements Addressed section with explicit GDD linkage
No ADR references APIs listed in docs/engine-reference/[engine]/deprecated-apis.md
All HIGH RISK engine domains (per VERSION.md) have been explicitly addressed
in the architecture document or flagged as open questions
Architecture traceability matrix has zero Foundation layer gaps
(all Foundation requirements must have ADR coverage before Pre-Production)
ADR Circular Dependency Check: For all ADRs in docs/architecture/, read each ADR's
"ADR Dependencies" / "Depends On" section. Build a dependency graph (ADR-A → ADR-B means
A depends on B). If any cycle is detected (e.g. A→B→A, or A→B→C→A):
Flag as FAIL: "Circular ADR dependency: [ADR-X] → [ADR-Y] → [ADR-X].
Neither can reach Accepted while the cycle exists. Remove one 'Depends On' edge to
break the cycle."
ADRs that touch post-cutoff engine APIs are flagged with Knowledge Risk: HIGH/MEDIUM
/architecture-review engine audit shows no deprecated API usage
All ADRs agree on the same engine version (no stale version references)
Gate: Pre-Production → Production
Required Artifacts:
Vertical slice exists in prototypes/ with a REPORT.md (run /vertical-slice) — recommended, not blocking; if absent, surface as CONCERNS
First sprint plan exists in production/sprints/
Art bible is complete (all 9 sections) and AD-ART-BIBLE sign-off verdict is recorded in design/art/art-bible.md
Entity inventory exists at design/assets/entity-inventory.md (recommended — run /asset-spec with no arguments to generate collaboratively from GDDs + art bible)
All MVP-tier GDDs from systems index are complete
Master architecture document exists at docs/architecture/architecture.md
At least 3 ADRs covering Foundation-layer decisions exist in docs/architecture/
All Foundation and Core layer ADRs have status Accepted (not Proposed) — stories cannot be unblocked until their governing ADR is accepted
Control manifest exists at docs/architecture/control-manifest.md
(generated by /create-control-manifest from Accepted ADRs)
Epics defined in production/epics/ with at least Foundation and Core
layer epics present (use /create-epics layer: foundation and
/create-epics layer: core to create them, then /create-stories [epic-slug]
for each epic)
Vertical Slice build exists and is playable (not just scope-defined) — recommended, not blocking; if absent, surface as CONCERNS
Vertical Slice has been playtested with at least 1 documented session — recommended, not blocking; if absent, surface as CONCERNS
Vertical Slice playtest report exists at production/playtests/ or equivalent — recommended, not blocking; if absent, surface as CONCERNS
UX specs exist for key screens: main menu, core gameplay HUD (at design/ux/), pause menu
HUD design document exists at design/ux/hud.md (if game has in-game HUD)
All key screen UX specs have passed /ux-review (verdict APPROVED or NEEDS REVISION accepted)
Quality Checks:
Core loop fun is validated — playtest data confirms the central mechanic is enjoyable, not just functional. Explicitly check the Vertical Slice playtest report.
UX specs cover all UI Requirements sections from MVP-tier GDDs
Interaction pattern library documents patterns used in key screens
Accessibility tier from design/accessibility-requirements.md is addressed in all key screen UX specs
Sprint plan references real story file paths from production/epics/
(not just GDDs — stories must embed GDD req ID + ADR reference)
Vertical Slice is COMPLETE, not just scoped — the build demonstrates the full core loop end-to-end. At least one complete [start → challenge → resolution] cycle works.
Architecture document has no unresolved open questions in Foundation or Core layers
All ADRs have Engine Compatibility sections stamped with the engine version
All ADRs have ADR Dependencies sections (even if all fields are "None")
Manual validation confirms GDDs + architecture + epics are coherent
(run /review-all-gdds and /architecture-review if not done recently)
Core fantasy is delivered — at least one playtester independently described an experience that matches the Player Fantasy section of the core system GDDs (without being prompted).
Vertical Slice Validation (only run these checks if a Vertical Slice was built):
A human has played through the core loop without developer guidance
The game communicates what to do within the first 2 minutes of play
No critical "fun blocker" bugs exist in the Vertical Slice build
The core mechanic feels good to interact with (this is a subjective check — ask the user)
Verdict rules for Vertical Slice:
Slice was built AND any validation item is NO → verdict is automatically FAIL. A broken
or unfun vertical slice should not advance to Production.
Slice was not built (skipped) → downgrade to CONCERNS only, not FAIL. Surface the risk
clearly: "Advancing without a validated Vertical Slice increases the risk of late-stage design
pivots. Recommended before committing full production scope." The user decides.
Skipping is a valid solo dev or time-constrained call. Shipping a broken one is not.
Gate: Production → Polish
Required Artifacts:
src/ has active code organized into subsystems
All core mechanics from GDD are implemented (cross-reference design/gdd/ with src/)
Main gameplay path is playable end-to-end
Test files exist in tests/unit/ and tests/integration/ covering Logic and Integration stories
All Logic stories from this sprint have corresponding unit test files in tests/unit/
Smoke check has been run with a PASS or PASS WITH WARNINGS verdict — report exists in production/qa/
QA plan exists in production/qa/ (generated by /qa-plan) covering this sprint or final production sprint
At least one QA plan exists in production/qa/ covering this production phase — run /qa-plan if missing (CONCERNS — advisory, not blocking)
QA sign-off report exists in production/qa/ (generated by /team-qa) with verdict APPROVED or APPROVED WITH CONDITIONS
At least 3 distinct playtest sessions documented in production/playtests/
Playtest reports cover: new player experience, mid-game systems, and difficulty curve
Fun hypothesis from Game Concept has been explicitly validated or revised
Quality Checks:
Tests are passing (run test suite via Bash)
No critical/blocker bugs in any bug tracker or known issues
Core loop plays as designed (compare to GDD acceptance criteria)
Performance is within budget (check technical-preferences.md targets)
Playtest findings have been reviewed and critical fun issues addressed (not just documented)
No "confusion loops" identified — no point in the game where >50% of playtesters got stuck without knowing why
Difficulty curve matches the Difficulty Curve design doc (if one exists at design/difficulty-curve.md)
All implemented screens have corresponding UX specs (no "designed in-code" screens)
Interaction pattern library is up-to-date with all patterns used in implementation
Accessibility compliance verified against committed tier in design/accessibility-requirements.md
Gate: Polish → Release
Required Artifacts:
All features from milestone plan are implemented
Content is complete (all levels, assets, dialogue referenced in design docs exist)
Localization strings are externalized (no hardcoded player-facing text in src/)
QA test plan exists (/qa-plan output in production/qa/)
QA sign-off report exists (/team-qa output — APPROVED or APPROVED WITH CONDITIONS)
All Must Have story test evidence is present (Logic/Integration: test files pass; Visual/Feel/UI: sign-off docs in production/qa/evidence/)
Smoke check passes cleanly (PASS verdict) on the release candidate build
No test regressions from previous sprint (test suite passes fully)
Balance data has been reviewed (/balance-check run)
Release checklist completed (/release-checklist or /launch-checklist run)
Store metadata prepared (if applicable)
Changelog / patch notes drafted
Quality Checks:
Full QA pass signed off by qa-lead
All tests passing
Performance targets met across all target platforms
No known critical, high, or medium-severity bugs
Accessibility basics covered (remapping, text scaling if applicable)
Localization verified for all target languages
Legal requirements met (EULA, privacy policy, age ratings if applicable)
Build compiles and packages cleanly
3. Run the Gate Check
Before running artifact checks, read docs/consistency-failures.md if it exists.
Extract entries whose Domain matches the target phase (e.g., if checking
Systems Design → Technical Setup, pull entries in Economy, Combat, or any GDD domain;
if checking Technical Setup → Pre-Production, pull entries in Architecture, Engine).
Carry these as context — recurring conflict patterns in the target domain warrant
increased scrutiny on those specific checks.
For each item in the target gate:
Artifact Checks
Use Glob and Read to verify files exist and have meaningful content
Don't just check existence — verify the file has real content (not just a template header)
For code checks, verify directory structure and file counts
Systems Design → Technical Setup gate — cross-GDD review check:
Use Glob('design/gdd/gdd-cross-review-*.md') to find the /review-all-gdds report.
If no file matches, mark the "cross-GDD review report exists" artifact as FAIL and
surface it prominently: "No /review-all-gdds report found in design/gdd/. Run
/review-all-gdds before advancing to Technical Setup."
If a file is found, read it and check the verdict line: a FAIL verdict means the
cross-GDD consistency check failed and must be resolved before advancing.
Quality Checks
For test checks: Run the test suite via Bash if a test runner is configured
For design review checks: Read the GDD and check for the 8 required sections
For performance checks: Read technical-preferences.md and compare against any
profiling data in tests/performance/ or recent /perf-profile output
For localization checks: Grep for hardcoded strings in src/
Cross-Reference Checks
Compare design/gdd/ documents against src/ implementations
Check that every system referenced in architecture docs has corresponding code
Verify sprint plans reference real work items
4. Collaborative Assessment
For items that can't be automatically verified, ask the user:
"I can't automatically verify that the core loop plays well. Has it been playtested?"
"No playtest report found. Has informal testing been done?"
"Performance profiling data isn't available. Would you like to run /perf-profile?"
Never assume PASS for unverifiable items. Mark them as MANUAL CHECK NEEDED.
4b. Director Panel Assessment
Apply review mode before spawning any director:
solo → skip all four directors. Note in output: "Director Panel skipped — Solo mode. Gate verdict based on artifact and quality checks only." Proceed to Phase 5.
lean → spawn all four directors (phase gates always run in lean mode — this is their purpose).
full → spawn all four directors as normal.
(Review mode was resolved in Phase 1. Use that stored value here.)
Before generating the final verdict, spawn all four directors as parallel subagents via Task using the parallel gate protocol from .claude/docs/director-gates.md. Issue all four Task calls simultaneously — do not wait for one before starting the next.
Pass to each: target phase name, list of artifacts present, and the context fields listed in that gate's definition.
Collect all four responses, then present the Director Panel summary:
## Director Panel Assessment
Creative Director: [READY / CONCERNS / NOT READY]
[feedback]
Technical Director: [READY / CONCERNS / NOT READY]
[feedback]
Producer: [READY / CONCERNS / NOT READY]
[feedback]
Art Director: [READY / CONCERNS / NOT READY]
[feedback]
Apply to the verdict:
Any director returns NOT READY → verdict is minimum FAIL (user may override with explicit acknowledgement)
Any director returns CONCERNS → verdict is minimum CONCERNS
All four READY → eligible for PASS (still subject to artifact and quality checks from Section 3)
5. Output the Verdict
## Gate Check: [Current Phase] → [Target Phase]
**Date**: [date]
**Checked by**: gate-check skill
### Required Artifacts: [X/Y present]
- [x] design/gdd/game-concept.md — exists, 2.4KB
- [ ] docs/architecture/ — MISSING (no ADRs found)
- [x] production/sprints/ — exists, 1 sprint plan
### Quality Checks: [X/Y passing]
- [x] GDD has 8/8 required sections
- [ ] Tests — FAILED (3 failures in tests/unit/)
- [?] Core loop playtested — MANUAL CHECK NEEDED
### Blockers
1. **No Architecture Decision Records** — Run `/architecture-decision` to create one
covering core system architecture before entering production.
2. **3 test failures** — Fix failing tests in tests/unit/ before advancing.
### Recommendations
- [Priority actions to resolve blockers]
- [Optional improvements that aren't blocking]
### Verdict: [PASS / CONCERNS / FAIL]
- **PASS**: All required artifacts present, all quality checks passing
- **CONCERNS**: Minor gaps exist but can be addressed during the next phase
- **FAIL**: Critical blockers must be resolved before advancing
5a. Chain-of-Verification
After drafting the verdict in Phase 5, challenge it before finalising.
Step 1 — Generate 5 challenge questions designed to disprove the verdict:
Tool-action requirement: At least 2 of the 5 challenge questions below must be answered by re-reading a specific file (Read tool) or re-running a specific check (Grep tool) — not by reflection alone. Mark these with [TOOL ACTION] to indicate a tool was used.
For a PASS draft:
"Which quality checks did I verify by actually reading a file, vs. inferring they passed?"
"Are there MANUAL CHECK NEEDED items I marked PASS without user confirmation? [TOOL ACTION] Re-scan the checklist for any [?] or MANUAL CHECK items."
"Did I confirm all listed artifacts have real content, not just empty headers? [TOOL ACTION] Re-read the file and check it has non-placeholder content."
"Could any blocker I dismissed as minor actually prevent the phase from succeeding?"
"Which single check am I least confident in, and why?"
For a CONCERNS draft:
"Could any listed CONCERN be elevated to a blocker given the project's current state?"
"Is the concern resolvable within the next phase, or does it compound over time?"
"Did I soften any FAIL condition into a CONCERN to avoid a harder verdict?"
"Are there artifacts I didn't check that could reveal additional blockers?"
"Do all the CONCERNS together create a blocking problem even if each is minor alone?"
For a FAIL draft:
"Have I accurately separated hard blockers from strong recommendations?"
"Are there any PASS items I was too lenient about?"
"Am I missing any additional blockers the user should know about?"
"Can I provide a minimal path to PASS — the specific 3 things that must change?"
"Is the fail condition resolvable, or does it indicate a deeper design problem?"
Step 2 — Answer each question independently.
Do NOT reference the draft verdict text — re-check specific files or ask the user.
Step 3 — Revise if needed:
If any answer reveals a missed blocker → upgrade verdict (PASS→CONCERNS or CONCERNS→FAIL)
If any answer reveals an over-stated blocker → downgrade only if citing specific evidence
If answers are consistent → confirm verdict unchanged
Step 4 — Note the verification in the final report output:
Chain-of-Verification: [N] questions checked — verdict [unchanged | revised from X to Y]
6. Update Stage on PASS
When the verdict is PASS and the user confirms they want to advance:
Write the new stage name to production/stage.txt (single line, no trailing newline)
This immediately updates the status line for all future sessions
Example: if passing the "Pre-Production → Production" gate:
echo -n "Production" > production/stage.txt
Always ask before writing: "Gate passed. May I update production/stage.txt to 'Production'?"
7. Closing Next-Step Widget
After the verdict is presented and any stage.txt update is complete, close with a structured next-step prompt using AskUserQuestion.
Tailor the options to the gate that just ran:
For systems-design PASS:
Gate passed. What would you like to do next?
[A] Run /create-architecture — produce your master architecture blueprint and ADR work plan (recommended next step)
[B] Design more GDDs first — return here when all MVP systems are complete
[C] Stop here for this session
Note for systems-design PASS: /create-architecture is the required next step before writing any ADRs. It produces the master architecture document and a prioritized list of ADRs to write. Running /architecture-decision without this step means writing ADRs without a blueprint — skip it at your own risk.
For technical-setup PASS:
Gate passed. What would you like to do next?
[A] Run /create-control-manifest — generate the layer rules manifest from your Accepted ADRs (do this first)
[B] Run /vertical-slice — build the Vertical Slice (do this before writing epics — validate fun first)
[C] Write more ADRs first — run /architecture-decision [next-system]
[D] Stop here for this session
Note for technical-setup PASS: The Pre-Production sequence is deliberately ordered
to validate fun before committing to detailed planning:
/create-control-manifest — extract technical rules from Accepted ADRs (required before epics)
/vertical-slice — build the Vertical Slice FIRST, before writing epics or stories
Playtest → /playtest-report — at least 1 session required to pass the Pre-Production gate; 3+ recommended before committing the full team
/ux-design [screen] — UX specs for main menu, core HUD, pause menu (if not done)
/create-epics layer:foundation then /create-epics layer:core — plan after fun is validated
/create-stories [epic-slug] for each epic
/sprint-plan new
Why prototype before epics? If the prototype reveals the core loop needs to change,
epics written before that discovery will be partially wrong. Validate fun cheaply first,
then plan in detail. This is the #1 lesson from GDC postmortem data.
For all other gates, offer the two most logical next steps for that phase plus "Stop here".
8. Follow-Up Actions
Based on the verdict, suggest specific next steps:
No art bible? → /art-bible to create the visual identity specification
Art bible exists but no asset specs? → /asset-spec system:[name] to generate per-asset visual specs and generation prompts from approved GDDs
No game concept? → /brainstorm to create one
No systems index? → /map-systems to decompose the concept into systems
Missing design docs? → /reverse-document or delegate to game-designer
Small design change needed? → /quick-design for changes under ~4 hours (bypasses full GDD pipeline)
No UX specs? → /ux-design [screen name] to author specs, or /team-ui [feature] for full pipeline
UX specs not reviewed? → /ux-review [file] or /ux-review all to validate
No accessibility requirements doc? → run /ux-design which creates both design/accessibility-requirements.md and design/ux/interaction-patterns.md in one step
No interaction pattern library? → /ux-design patterns to initialize it
GDDs not cross-reviewed? → /review-all-gdds (run after all MVP GDDs are individually approved)
Cross-GDD consistency issues? → fix flagged GDDs, then re-run /review-all-gdds
No test framework? → /test-setup to scaffold the framework for your engine
No QA plan for current sprint? → /qa-plan sprint to generate one before implementation begins
Missing ADRs? → /architecture-decision for individual decisions
No master architecture doc? → /create-architecture for the full blueprint
ADRs missing engine compatibility sections? → Re-run /architecture-decision
or manually add Engine Compatibility sections to existing ADRs
Missing control manifest? → /create-control-manifest (requires Accepted ADRs)
Missing epics? → /create-epics layer: foundation then /create-epics layer: core (requires control manifest)
Missing stories for an epic? → /create-stories [epic-slug] (run after each epic is created)
Stories not implementation-ready? → /story-readiness to validate stories before developers pick them up
Tests failing? → delegate to lead-programmer or qa-tester
No playtest data? → /playtest-report
No playtest sessions beyond the minimum? → Additional sessions give more reliable signal. 3+ total is recommended before committing the full team. Use /playtest-report to structure findings.
No Difficulty Curve doc? → Create design/difficulty-curve.md from the template at .claude/docs/templates/difficulty-curve.md — or use /quick-design "difficulty curve" for a guided session.
No player journey map? → Create design/player-journey.md from the template at .claude/docs/templates/player-journey.md — or author it collaboratively using /ux-design Phase 2b.
Need a quick sprint check? → /sprint-status for current sprint progress snapshot
Performance unknown? → /perf-profile
Not localized? → /localize
Ready for release? → /launch-checklist
Collaborative Protocol
This skill follows the collaborative design principle:
Scan first: Check all artifacts and quality gates
Ask about unknowns: Don't assume PASS for things you can't verify
Present findings: Show the full checklist with status
User decides: The verdict is a recommendation — the user makes the final call
Get approval: "May I write this gate check report to production/gate-checks/?"
Never auto-fix: If required artifacts are missing, report the FAIL verdict and
name the skill to run (e.g. "run /test-setup"). Do NOT create missing files or
re-run the gate automatically. Creating files to manufacture a PASS defeats the
gate's purpose.
Never block a user from advancing — the verdict is advisory. Document the risks
and let the user decide whether to proceed despite concerns.
