ECS Core Test

Run 8 test suites covering ECS system registration, component schemas, Transform sync, pause/step/resume, system toggle, entity discovery, snapshot/diff, and stability.

All tool calls go through npx iwsdk from the example workspace. The helper below keeps the existing MCP-style tool names, but it resolves them through iwsdk mcp inspect and then executes the matching CLI command directly.

Configuration:

• EXAMPLE_DIR: /Users/felixz/Projects/immersive-web-sdk/examples/poke
• ROOT: /Users/felixz/Projects/immersive-web-sdk

SHORTHAND: Throughout this document, MCPCALL means this shell function:

MCPCALL() {
  local tool=""
  local args=""
  local timeout=""
  while [ "$#" -gt 0 ]; do
    case "$1" in
      --tool) tool="$2"; shift 2 ;;
      --args) args="$2"; shift 2 ;;
      --timeout) timeout="$2"; shift 2 ;;
      *) echo "Unknown argument: $1" >&2; return 1 ;;
    esac
  done

  node --input-type=module - "$tool" "${args:-}" "${timeout:-}" <<'EOF'
import { spawnSync } from 'node:child_process';

const [toolName, rawArgs, timeout] = process.argv.slice(2);
const inspect = spawnSync('npx', ['iwsdk', 'mcp', 'inspect'], {
  cwd: process.cwd(),
  encoding: 'utf8',
});
if (inspect.status !== 0) {
  if (inspect.stderr) process.stderr.write(inspect.stderr);
  process.exit(inspect.status ?? 1);
}

const parsed = JSON.parse(inspect.stdout);
const tool = parsed.data.tools.find((entry) => entry.mcpName === toolName);
if (!tool) {
  console.error(`Unknown tool: ${toolName}`);
  process.exit(1);
}

const cliArgs = ['iwsdk', ...tool.cliPath.split(' ')];
if (rawArgs) cliArgs.push('--input-json', rawArgs);
if (timeout) cliArgs.push('--timeout', timeout);

const result = spawnSync('npx', cliArgs, {
  cwd: process.cwd(),
  encoding: 'utf8',
});
if (result.stdout) process.stdout.write(result.stdout);
if (result.stderr) process.stderr.write(result.stderr);
process.exit(result.status ?? 1);
EOF
}

Tool calling pattern: Every tool call is a Bash command using the MCPCALL shorthand:

MCPCALL --tool <TOOL_NAME> --args '<JSON_ARGS>' 2>/dev/null

• <TOOL_NAME> uses MCP-style names (e.g. browser_reload_page, xr_accept_session). The shell helper resolves them to direct CLI commands.
• <JSON_ARGS> is a JSON object string. Omit --args if no arguments needed.
• Output is JSON on stdout. Parse it to check assertions.
• Use --timeout 20000 for operations that may take longer (reload, accept_session, screenshot).
• Running from the example workspace (or a child directory within it) is required so npx iwsdk can resolve the nearest IWSDK app root.

IMPORTANT: Run each Bash command one at a time. Parse the JSON output and verify assertions before moving to the next command. Do NOT chain multiple MCPCALL commands together.

IMPORTANT: When the instructions say "wait N seconds", use sleep N as a separate Bash command.

Step 1: Install Dependencies

cd /Users/felixz/Projects/immersive-web-sdk/examples/poke && npm run fresh:install

Wait for this to complete before proceeding.

Step 2: Start Dev Server

Start the dev server as a background task using the Bash tool's run_in_background: true parameter:

cd /Users/felixz/Projects/immersive-web-sdk/examples/poke && npm run dev

IMPORTANT: This command MUST be run with run_in_background: true on the Bash tool — do NOT append & to the command itself.

Once the background task is launched, poll the output for Vite's ready message (up to 60s). You can also run npx iwsdk dev status from the example directory until state.running becomes true. You do not need to extract or manage the port yourself; all subsequent MCPCALL commands resolve the active runtime through the CLI.

If the server fails to start within 60 seconds, report FAIL for all suites and skip to Step 5.

Step 3: Verify Connectivity

MCPCALL --tool ecs_list_systems 2>/dev/null

This must return JSON with a list of systems. If it fails:

1. Check the dev server output for errors
2. Try killing and restarting the server (Step 2)
3. If it still fails, report FAIL for all suites and skip to Step 5

Step 4: Run Test Suites

Pre-test Setup

Run these commands in order:

1. MCPCALL --tool browser_reload_page --timeout 20000 2>/dev/null Then: sleep 3

2. MCPCALL --tool xr_accept_session --timeout 20000 2>/dev/null Then: sleep 2

3. MCPCALL --tool browser_get_console_logs --args '{"level":["error","warn"]}' 2>/dev/null Assert: result should be empty or have no errors/warnings

Suite 1: System Registration

Test 1.1: List All Systems

MCPCALL --tool ecs_list_systems 2>/dev/null

Assert these framework systems are present with correct priorities:

Also verify entity counts:

• InputSystem: rayInteractables >= 1, pokeInteractables >= 1
• TransformSystem: transform >= 5
• LevelSystem: levelEntities >= 4

Suite 2: Component Registration

Test 2.1: List All Components

MCPCALL --tool ecs_list_components 2>/dev/null

Assert these components are present:

• Transform with fields: position (Vec3), orientation (Vec4), scale (Vec3), parent (Entity)
• Visibility with field: isVisible (Boolean, default: true)
• LevelRoot (no fields — marker)
• LevelTag with field: id (String)
• PanelUI with fields: config (String), maxWidth (Float32), maxHeight (Float32)
• AudioSource with fields: src (FilePath), volume (Float32)

Test 2.2: Transform Default Values From the ecs_list_components output, verify Transform field defaults:

• position default: [NaN, NaN, NaN]
• orientation default: [NaN, NaN, NaN, NaN]
• scale default: [NaN, NaN, NaN]

Suite 3: Transform Sync (ECS <-> Object3D)

Test 3.1: Modify Transform Position

1. Find an entity with LevelTag:

   MCPCALL --tool ecs_find_entities --args '{"withComponents":["LevelTag"]}' 2>/dev/null

   Pick the first entity's entityIndex.

2. Get the scene hierarchy to find the entity's Object3D UUID:

   MCPCALL --tool scene_get_hierarchy --args '{"maxDepth":3}' 2>/dev/null

   Find the node matching the entity index.

3. Get initial transform:

   MCPCALL --tool scene_get_object_transform --args '{"uuid":"<UUID>"}' 2>/dev/null

4. Set position via ECS:

   MCPCALL --tool ecs_set_component --args '{"entityIndex":<N>,"componentId":"Transform","field":"position","value":"[0, 2, -1]"}' 2>/dev/null

5. Verify Object3D moved:

   MCPCALL --tool scene_get_object_transform --args '{"uuid":"<UUID>"}' 2>/dev/null

   Assert: localPosition matches [0, 2, -1] (within tolerance of 0.01).

Suite 4: ECS Pause / Step / Resume

Test 4.1: Pause

MCPCALL --tool ecs_pause 2>/dev/null

Assert: paused === true, systemCount >= 12

Test 4.2: Step

MCPCALL --tool ecs_step --args '{"count":5}' 2>/dev/null

Assert: framesAdvanced === 5

Test 4.3: Resume

MCPCALL --tool ecs_resume 2>/dev/null

Assert: paused === false

Suite 5: System Toggle

Test 5.1: Pause a System

MCPCALL --tool ecs_toggle_system --args '{"name":"GrabSystem","paused":true}' 2>/dev/null

Assert: isPaused === true

Test 5.2: Resume a System

MCPCALL --tool ecs_toggle_system --args '{"name":"GrabSystem","paused":false}' 2>/dev/null

Assert: isPaused === false

Suite 6: Entity Discovery

Test 6.1: Find by Component

MCPCALL --tool ecs_find_entities --args '{"withComponents":["LevelRoot"]}' 2>/dev/null

Assert: exactly 1 entity

MCPCALL --tool ecs_find_entities --args '{"withComponents":["Transform"]}' 2>/dev/null

Assert: returns entities (count >= 5)

MCPCALL --tool ecs_find_entities --args '{"withComponents":["LevelTag"]}' 2>/dev/null

Assert: returns entities (count >= 4)

Test 6.2: Find by Name Pattern

MCPCALL --tool ecs_find_entities --args '{"namePattern":"LevelRoot"}' 2>/dev/null

Assert: matches entity named "LevelRoot"

Test 6.3: Exclude Components

MCPCALL --tool ecs_find_entities --args '{"withComponents":["Transform"],"withoutComponents":["LevelTag"]}' 2>/dev/null

Assert: returns only persistent entities (fewer than the full Transform set)

Suite 7: Snapshot & Diff

Test 7.1: Snapshot

MCPCALL --tool ecs_snapshot --args '{"label":"baseline"}' 2>/dev/null

Assert: entityCount >= 5, componentCount >= 20

Test 7.2: Modify and Diff

1. Find an entity with LevelTag:

   MCPCALL --tool ecs_find_entities --args '{"withComponents":["LevelTag"]}' 2>/dev/null

2. Set its position:

   MCPCALL --tool ecs_set_component --args '{"entityIndex":<N>,"componentId":"Transform","field":"position","value":"[1, 1, 1]"}' 2>/dev/null

3. Take second snapshot:

   MCPCALL --tool ecs_snapshot --args '{"label":"modified"}' 2>/dev/null

4. Diff:

   MCPCALL --tool ecs_diff --args '{"from":"baseline","to":"modified"}' 2>/dev/null

   Assert: diff shows Transform.position changed to [1, 1, 1]

Suite 8: Stability

MCPCALL --tool browser_get_console_logs --args '{"count":30,"level":["error","warn"]}' 2>/dev/null

Assert: No application-level errors or warnings. Pre-existing 404 resource errors from page load are acceptable.

Step 5: Cleanup & Results

Kill the dev server:

cd /Users/felixz/Projects/immersive-web-sdk/examples/poke && npx iwsdk dev down

Output a summary table:

| Suite                    | Result    |
|--------------------------|-----------|
| 1. System Registration   | PASS/FAIL |
| 2. Component Registration| PASS/FAIL |
| 3. Transform Sync        | PASS/FAIL |
| 4. Pause/Step/Resume     | PASS/FAIL |
| 5. System Toggle         | PASS/FAIL |
| 6. Entity Discovery      | PASS/FAIL |
| 7. Snapshot & Diff       | PASS/FAIL |
| 8. Stability             | PASS/FAIL |

If any suite fails, include which assertion failed and actual vs expected values.

Recovery

If at any point a transient error occurs (server crash, WebSocket timeout, connection refused, etc.) that is NOT caused by a source code bug:

1. Stop the dev server: cd /Users/felixz/Projects/immersive-web-sdk/examples/poke && npx iwsdk dev down
2. Restart: re-run Step 2 to start a fresh dev server
3. Re-run the Pre-test Setup (reload, accept session)
4. Retry the failed suite

Only give up after one retry attempt per suite. If the same suite fails twice, mark it FAIL and continue to the next suite.

Known Issues & Workarounds

Transform NaN defaults

Transform fields default to [NaN, NaN, NaN] — by design. NaN sentinel means "don't overwrite existing Object3D value".

UUIDs change on reload

Three.js Object3D UUIDs regenerate on page reload. Always call scene_get_hierarchy after reload.

ecs_step timeout

ecs_step has a 5-second timeout per step. If render loop is inactive, steps may fail.

Entity indices change on reload

Never cache entity indices across reloads. Always re-discover via ecs_find_entities.

Console log noise

Some warnings (e.g., TLS self-signed cert) are expected and should be ignored. Only check for application-level errors/warnings.