Phaser Analyze

Phaser 4 Brownfield Project Analysis

Perform a comprehensive analysis of an existing Phaser 4 project to assess architecture quality, identify performance risks, flag API correctness issues, and produce a prioritized improvement roadmap.

Analysis Process

Follow all five phases in order. Do not skip phases — each builds on the previous.

Phase 1 — Discovery

Gather raw facts about the project before making any judgments.

• Read package.json for dependencies and Phaser version
• Glob for all .ts/.js files in src/
• Read main.ts for GameConfig
• Identify all scenes: grep "extends Phaser.Scene" across src/
• Map scene graph: grep for this.scene.start, this.scene.launch, this.scene.stop
• Identify all custom game objects: grep "extends Phaser.Physics" or grep "extends Phaser.GameObjects"
• Count total source files and lines of code

Phase 2 — Architecture Assessment

Evaluate the structural quality of the codebase.

• Scene count and organization — Are scenes in src/scenes/? Are there too many or too few for the game's complexity?
• State management pattern — Registry vs globals vs module state. Search for window., module-level let/var declarations.
• Asset loading strategy — Centralized PreloaderScene vs scattered preload() methods across scenes.
• Code organization — Does the project follow scenes/, objects/, managers/ conventions?
• Cross-scene coupling analysis — Direct references vs event bus vs Registry. Search for this.registry, this.events.emit, this.scene.get.

Rate the architecture A through F based on findings:

• A — Clean separation, centralized loading, event-driven communication
• B — Minor organizational gaps, mostly well-structured
• C — Some coupling issues, mixed patterns, functional but messy
• D — Significant structural problems, globals, scattered loading
• F — No discernible architecture, everything in one file or deeply entangled

Phase 3 — Performance Audit

Identify runtime performance risks.

• Object pooling: Search for classType/maxSize in group declarations. Flag physics groups created with this.physics.add.group() that lack maxSize — these leak objects.
• Particle emitter caps: Search for particle emitters missing maxParticles. Uncapped emitters can spike frame time.
• Static vs dynamic groups: Check if platforms, walls, and other immovable bodies use staticGroup() (correct) vs group() (wastes physics cycles).
• Update loop weight: Read each scene's update() method. Flag complex logic, object allocations (new), or heavy iteration inside update().
• Texture atlas usage: Count individual this.load.image() calls vs this.load.atlas() calls. More than 15 individual image loads is a red flag — should be packed into atlases.
• Physics body count: Estimate total active physics bodies from group declarations and individual this.physics.add.* calls.

Phase 4 — API Correctness

Check for deprecated, removed, or misused APIs.

• v3 API scan: Search for removed APIs — Geom.Point, Math.PI2, Phaser.Structs, Camera3D, Layer3D, FacebookInstant, Create.GenerateTexture, TileSprite.setCrop.
• TypeScript strictness: Grep for as any, @ts-ignore, untyped function parameters. These hide real bugs.
• Asset key consistency: Cross-reference this.load.* keys with this.add.*/this.physics.add.* keys. Mismatched keys cause silent texture-missing errors.
• Scene key registration: Verify all scene classes appear in the GameConfig scene array in main.ts.
• Physics body creation: Flag this.add.sprite() calls that should be this.physics.add.sprite() (sprites expected to have physics but created without a body).
• DynamicTexture/RenderTexture: Check for missing .render() calls after drawing operations.

Phase 5 — Best Practice Check

Verify the project follows Phaser 4 best practices.

• Lifecycle discipline: preload() should only load assets, create() should only build the scene, update() should be lean (no asset loading, no object creation).
• Cleanup on shutdown: Scenes should clean up — look for this.events.off, this.sound.stopAll(), timer destruction, this.events.on('shutdown', ...).
• Camera bounds: Camera bounds should match world or tilemap bounds. Search for this.cameras.main.setBounds and compare with world/map dimensions.
• Input keyboard null assertions: this.input.keyboard can be null in Phaser 4. Check for this.input.keyboard! or proper null guards.
• Physics debug flag: debug: true in physics config should be false for production. Flag if present.
• Console statements: Count console.log/console.warn/console.error calls. These should be gated behind import.meta.env.DEV or removed for production.

Output Format

Produce a structured report with these sections:

1. Project Summary — File count, scene count, lines of code, estimated complexity (small/medium/large).
2. Architecture Score — Letter grade (A/B/C/D/F) with rationale for the rating.
3. Performance Risks — Ordered by severity (critical/high/medium/low) with a concrete fix suggestion for each.
4. Code Quality Issues — With file:line references where possible.
5. Improvement Roadmap — Prioritized refactoring steps, ordered by impact vs effort.
6. Quick Wins — 3-5 changes that can be made immediately for noticeable improvement.

Related Skills

• Use /phaser-migrate to fix any Phaser v3 API issues found in Phase 4.
• Use /phaser-physics for implementing object pooling and fixing physics group issues from Phase 3.
• Use the phaser-debugger agent for investigating runtime performance issues flagged in Phase 3.

Reference Files

• references/analysis-checklist.md — Complete checklist with grep patterns, severity ratings, and fix references for all checks.
• references/performance-playbook.md — Nine-phase Phaser 4 performance playbook for mid-range mobile targets: measurement-first prompting, per-frame allocation elimination, registry throttling, audio lazy-load, VFX pooling, spatial grid, atlas packing, event throttling, AI tick-skip with real delta, tween cleanup. Read when FPS is below target or memory grows during gameplay.

Automated Pre-scan

Before starting the manual deep review, run the automated analysis script:

bash "${CLAUDE_PLUGIN_ROOT}/skills/phaser-analyze/scripts/analyze-project.sh"

This provides baseline metrics and flags obvious issues. Use the script output as a starting point, then perform the full 5-phase analysis by reading actual source files.