fix: namespace claude managed install paths

README.md

@@ -245,7 +245,7 @@ This is intentional. Anthropic marketplace/plugin installs are keyed by a canoni
 >
 > If you already installed ECC via `/plugin install`, **do not run `./install.sh --profile full`, `.\install.ps1 --profile full`, or `npx ecc-install --profile full` afterward**. The plugin already loads ECC skills, commands, and hooks. Running the full installer after a plugin install copies those same surfaces into your user directories and can create duplicate skills plus duplicate runtime behavior.
 >
-> For plugin installs, manually copy only the `rules/` directories you want. Start with `rules/common` plus one language or framework pack you actually use. Do not copy every rules directory unless you explicitly want all of that context in Claude.
+> For plugin installs, manually copy only the `rules/` directories you want under `~/.claude/rules/ecc/`. Start with `rules/common` plus one language or framework pack you actually use. Do not copy every rules directory unless you explicitly want all of that context in Claude.
 >
 > Use the full installer only when you are doing a fully manual ECC install instead of the plugin path.
 >
@@ -259,10 +259,10 @@ cd everything-claude-code
 # Install dependencies (pick your package manager)
 npm install        # or: pnpm install | yarn install | bun install
 
-# Plugin install path: copy only rules
-mkdir -p ~/.claude/rules
-cp -R rules/common ~/.claude/rules/
-cp -R rules/typescript ~/.claude/rules/
+# Plugin install path: copy only ECC rules into an ECC-owned namespace
+mkdir -p ~/.claude/rules/ecc
+cp -R rules/common ~/.claude/rules/ecc/
+cp -R rules/typescript ~/.claude/rules/ecc/
 
 # Fully manual ECC install path (use this instead of /plugin install)
 # ./install.sh --profile full
@@ -271,10 +271,10 @@ cp -R rules/typescript ~/.claude/rules/
 ```powershell
 # Windows PowerShell
 
-# Plugin install path: copy only rules
-New-Item -ItemType Directory -Force -Path "$HOME/.claude/rules" | Out-Null
-Copy-Item -Recurse rules/common "$HOME/.claude/rules/"
-Copy-Item -Recurse rules/typescript "$HOME/.claude/rules/"
+# Plugin install path: copy only ECC rules into an ECC-owned namespace
+New-Item -ItemType Directory -Force -Path "$HOME/.claude/rules/ecc" | Out-Null
+Copy-Item -Recurse rules/common "$HOME/.claude/rules/ecc/"
+Copy-Item -Recurse rules/typescript "$HOME/.claude/rules/ecc/"
 
 # Fully manual ECC install path (use this instead of /plugin install)
 # .\install.ps1 --profile full
@@ -303,7 +303,7 @@ If you choose this path, stop there. Do not also run `/plugin install`.
 
 If ECC feels duplicated, intrusive, or broken, do not keep reinstalling it on top of itself.
 
-- **Plugin path:** remove the plugin from Claude Code, then delete the specific rule folders you manually copied under `~/.claude/rules/`.
+- **Plugin path:** remove the plugin from Claude Code, then delete the specific rule folders you manually copied under `~/.claude/rules/ecc/`.
 - **Manual installer / CLI path:** from the repo root, preview removal first:
 
 ```bash
@@ -574,7 +574,7 @@ everything-claude-code/
 |   |-- verify.md           # /verify - Prefer the verification-loop skill
 |   |-- orchestrate.md      # /orchestrate - Prefer dmux-workflows or multi-workflow
 |
-|-- rules/            # Always-follow guidelines (copy to ~/.claude/rules/)
+|-- rules/            # Always-follow guidelines (copy to ~/.claude/rules/ecc/)
 |   |-- README.md            # Structure overview and installation guide
 |   |-- common/              # Language-agnostic principles
 |   |   |-- coding-style.md    # Immutability, file organization
@@ -791,17 +791,17 @@ This gives you instant access to all commands, agents, skills, and hooks.
 > git clone https://github.com/affaan-m/everything-claude-code.git
 >
 > # Option A: User-level rules (applies to all projects)
-> mkdir -p ~/.claude/rules
-> cp -r everything-claude-code/rules/common ~/.claude/rules/
-> cp -r everything-claude-code/rules/typescript ~/.claude/rules/   # pick your stack
-> cp -r everything-claude-code/rules/python ~/.claude/rules/
-> cp -r everything-claude-code/rules/golang ~/.claude/rules/
-> cp -r everything-claude-code/rules/php ~/.claude/rules/
+> mkdir -p ~/.claude/rules/ecc
+> cp -r everything-claude-code/rules/common ~/.claude/rules/ecc/
+> cp -r everything-claude-code/rules/typescript ~/.claude/rules/ecc/   # pick your stack
+> cp -r everything-claude-code/rules/python ~/.claude/rules/ecc/
+> cp -r everything-claude-code/rules/golang ~/.claude/rules/ecc/
+> cp -r everything-claude-code/rules/php ~/.claude/rules/ecc/
 >
 > # Option B: Project-level rules (applies to current project only)
-> mkdir -p .claude/rules
-> cp -r everything-claude-code/rules/common .claude/rules/
-> cp -r everything-claude-code/rules/typescript .claude/rules/     # pick your stack
+> mkdir -p .claude/rules/ecc
+> cp -r everything-claude-code/rules/common .claude/rules/ecc/
+> cp -r everything-claude-code/rules/typescript .claude/rules/ecc/     # pick your stack
 > ```
 
 ---
@@ -818,21 +818,22 @@ git clone https://github.com/affaan-m/everything-claude-code.git
 cp everything-claude-code/agents/*.md ~/.claude/agents/
 
 # Copy rules directories (common + language-specific)
-mkdir -p ~/.claude/rules
-cp -r everything-claude-code/rules/common ~/.claude/rules/
-cp -r everything-claude-code/rules/typescript ~/.claude/rules/   # pick your stack
-cp -r everything-claude-code/rules/python ~/.claude/rules/
-cp -r everything-claude-code/rules/golang ~/.claude/rules/
-cp -r everything-claude-code/rules/php ~/.claude/rules/
+mkdir -p ~/.claude/rules/ecc
+cp -r everything-claude-code/rules/common ~/.claude/rules/ecc/
+cp -r everything-claude-code/rules/typescript ~/.claude/rules/ecc/   # pick your stack
+cp -r everything-claude-code/rules/python ~/.claude/rules/ecc/
+cp -r everything-claude-code/rules/golang ~/.claude/rules/ecc/
+cp -r everything-claude-code/rules/php ~/.claude/rules/ecc/
 
 # Copy skills first (primary workflow surface)
 # Recommended (new users): core/general skills only
-cp -r everything-claude-code/.agents/skills/* ~/.claude/skills/
-cp -r everything-claude-code/skills/search-first ~/.claude/skills/
+mkdir -p ~/.claude/skills/ecc
+cp -r everything-claude-code/.agents/skills/* ~/.claude/skills/ecc/
+cp -r everything-claude-code/skills/search-first ~/.claude/skills/ecc/
 
 # Optional: add niche/framework-specific skills only when needed
 # for s in django-patterns django-tdd laravel-patterns springboot-patterns; do
-# cp -r everything-claude-code/skills/$s ~/.claude/skills/
+# cp -r everything-claude-code/skills/$s ~/.claude/skills/ecc/
 # done
 
 # Optional: keep maintained slash-command compatibility during migration
@@ -1059,8 +1060,8 @@ Yes. Use Option 2 (manual installation) and copy only what you need:
 cp everything-claude-code/agents/*.md ~/.claude/agents/
 
 # Just rules
-mkdir -p ~/.claude/rules/
-cp -r everything-claude-code/rules/common ~/.claude/rules/
+mkdir -p ~/.claude/rules/ecc/
+cp -r everything-claude-code/rules/common ~/.claude/rules/ecc/
 ```
 
 Each component is fully independent.

docs/SELECTIVE-INSTALL-ARCHITECTURE.md

@@ -640,7 +640,7 @@ Suggested operation shape:
   "kind": "copy",
   "moduleId": "rules-core",
   "source": "rules/common/coding-style.md",
-  "destination": "/Users/example/.claude/rules/common/coding-style.md",
+  "destination": "/Users/example/.claude/rules/ecc/common/coding-style.md",
   "ownership": "managed",
   "overwritePolicy": "replace"
 }
@@ -711,7 +711,7 @@ Suggested payload:
     {
       "kind": "copy",
       "moduleId": "rules-core",
-      "destination": "/Users/example/.claude/rules/common/coding-style.md",
+      "destination": "/Users/example/.claude/rules/ecc/common/coding-style.md",
       "digest": "sha256:..."
     }
   ]

scripts/install-apply.js

@@ -27,7 +27,7 @@ Usage: install.sh [--target <${LEGACY_INSTALL_TARGETS.join('|')}>] [--dry-run] [
        install.sh [--dry-run] [--json] --config <path>
 
 Targets:
-  claude       (default) - Install ECC into ~/.claude/ (hooks, commands, agents, rules, skills)
+  claude       (default) - Install ECC into ~/.claude/ with managed rules/skills under rules/ecc and skills/ecc
   cursor       - Install rules, hooks, and bundled Cursor configs to ./.cursor/
   antigravity  - Install rules, workflows, skills, and agents to ./.agent/
 

scripts/lib/install-executor.js

@@ -14,6 +14,7 @@ const {
 const { getInstallTargetAdapter } = require('./install-targets/registry');
 
 const LANGUAGE_NAME_PATTERN = /^[a-zA-Z0-9_-]+$/;
+const CLAUDE_ECC_NAMESPACE = 'ecc';
 const EXCLUDED_GENERATED_SOURCE_SUFFIXES = [
   '/ecc-install-state.json',
   '/ecc/install-state.json',
@@ -264,7 +265,7 @@ function isDirectoryNonEmpty(dirPath) {
 function planClaudeLegacyInstall(context) {
   const adapter = getInstallTargetAdapter('claude');
   const targetRoot = adapter.resolveRoot({ homeDir: context.homeDir });
-  const rulesDir = context.claudeRulesDir || path.join(targetRoot, 'rules');
+  const rulesDir = context.claudeRulesDir || path.join(targetRoot, 'rules', CLAUDE_ECC_NAMESPACE);
   const installStatePath = adapter.getInstallStatePath({ homeDir: context.homeDir });
   const operations = [];
   const warnings = [];

scripts/lib/install-targets/claude-home.js

@@ -1,4 +1,46 @@
-const { createInstallTargetAdapter } = require('./helpers');
+const path = require('path');
+
+const {
+  createInstallTargetAdapter,
+  createRemappedOperation,
+  isForeignPlatformPath,
+  normalizeRelativePath,
+} = require('./helpers');
+
+const CLAUDE_ECC_NAMESPACE = 'ecc';
+
+function getClaudeManagedDestinationPath(adapter, sourceRelativePath, input) {
+  const normalizedSourcePath = normalizeRelativePath(sourceRelativePath);
+  const targetRoot = adapter.resolveRoot(input);
+
+  if (normalizedSourcePath === 'rules') {
+    return path.join(targetRoot, 'rules', CLAUDE_ECC_NAMESPACE);
+  }
+
+  if (normalizedSourcePath.startsWith('rules/')) {
+    return path.join(
+      targetRoot,
+      'rules',
+      CLAUDE_ECC_NAMESPACE,
+      normalizedSourcePath.slice('rules/'.length)
+    );
+  }
+
+  if (normalizedSourcePath === 'skills') {
+    return path.join(targetRoot, 'skills', CLAUDE_ECC_NAMESPACE);
+  }
+
+  if (normalizedSourcePath.startsWith('skills/')) {
+    return path.join(
+      targetRoot,
+      'skills',
+      CLAUDE_ECC_NAMESPACE,
+      normalizedSourcePath.slice('skills/'.length)
+    );
+  }
+
+  return null;
+}
 
 module.exports = createInstallTargetAdapter({
   id: 'claude-home',
@@ -7,4 +49,39 @@ module.exports = createInstallTargetAdapter({
   rootSegments: ['.claude'],
   installStatePathSegments: ['ecc', 'install-state.json'],
   nativeRootRelativePath: '.claude-plugin',
+  planOperations(input, adapter) {
+    const modules = Array.isArray(input.modules)
+      ? input.modules
+      : (input.module ? [input.module] : []);
+    const planningInput = {
+      repoRoot: input.repoRoot,
+      projectRoot: input.projectRoot,
+      homeDir: input.homeDir,
+    };
+
+    return modules.flatMap(module => {
+      const paths = Array.isArray(module.paths) ? module.paths : [];
+      return paths
+        .filter(p => !isForeignPlatformPath(p, adapter.target))
+        .map(sourceRelativePath => {
+          const managedDestinationPath = getClaudeManagedDestinationPath(
+            adapter,
+            sourceRelativePath,
+            planningInput
+          );
+
+          if (managedDestinationPath) {
+            return createRemappedOperation(
+              adapter,
+              module.id,
+              sourceRelativePath,
+              managedDestinationPath,
+              { strategy: 'preserve-relative-path' }
+            );
+          }
+
+          return adapter.createScaffoldOperation(module.id, sourceRelativePath, planningInput);
+        });
+    });
+  },
 });

tests/lib/install-executor.test.js

@@ -79,9 +79,11 @@ function writeManifestSourceFixture(root) {
         kind: 'fixture',
         description: 'Fixture module',
         paths: [
+          'rules',
           'src',
           'standalone.txt',
           'missing.txt',
+          'skills/demo',
           path.join('runtime', 'ecc', 'install-state.json'),
           '.claude-plugin',
         ],
@@ -107,6 +109,8 @@ function writeManifestSourceFixture(root) {
   writeFile(root, path.join('src', 'node_modules', 'ignored.js'), 'console.log("ignored");\n');
   writeFile(root, path.join('src', '.git', 'ignored.js'), 'console.log("ignored");\n');
   writeFile(root, path.join('src', 'nested', 'ecc-install-state.json'), '{}\n');
+  writeFile(root, path.join('rules', 'common', 'coding-style.md'), '# Common\n');
+  writeFile(root, path.join('skills', 'demo', 'SKILL.md'), '# Demo\n');
   writeFile(root, 'standalone.txt', 'standalone\n');
   writeFile(root, path.join('runtime', 'ecc', 'install-state.json'), '{}\n');
   writeJson(root, path.join('.claude-plugin', 'plugin.json'), { name: 'fixture' });
@@ -194,6 +198,35 @@ function runTests() {
     }
   })) passed++; else failed++;
 
+  if (test('plans Claude legacy rules under the default ECC-managed rules directory', () => {
+    const sourceRoot = createTempDir('install-executor-source-');
+    const homeDir = createTempDir('install-executor-home-');
+    const projectRoot = createTempDir('install-executor-project-');
+    try {
+      writeLegacySourceFixture(sourceRoot);
+      writeFile(homeDir, path.join('.claude', 'rules', 'common', 'coding-style.md'), '# User custom rule\n');
+
+      const plan = createLegacyInstallPlan({
+        sourceRoot,
+        homeDir,
+        projectRoot,
+        target: 'claude',
+        languages: ['typescript'],
+      });
+
+      const managedRulesDir = path.join(homeDir, '.claude', 'rules', 'ecc');
+      assert.strictEqual(plan.installRoot, managedRulesDir);
+      assert.ok(operationFor(plan, path.join('.claude', 'rules', 'ecc', 'common', 'coding-style.md')));
+      assert.ok(operationFor(plan, path.join('.claude', 'rules', 'ecc', 'typescript', 'testing.md')));
+      assert.ok(!operationFor(plan, path.join('.claude', 'rules', 'common', 'coding-style.md')));
+      assert.ok(!plan.warnings.some(warning => warning.includes('files may be overwritten')));
+    } finally {
+      cleanup(sourceRoot);
+      cleanup(homeDir);
+      cleanup(projectRoot);
+    }
+  })) passed++; else failed++;
+
   if (test('plans Cursor legacy assets and JSON merge payloads', () => {
     const sourceRoot = createTempDir('install-executor-source-');
     const projectRoot = createTempDir('install-executor-project-');
@@ -307,6 +340,8 @@ function runTests() {
       ));
       assert.ok(normalizedSources.includes('src/app.js'));
       assert.ok(normalizedSources.includes('src/nested/feature.js'));
+      assert.ok(normalizedSources.includes('rules/common/coding-style.md'));
+      assert.ok(normalizedSources.includes('skills/demo/SKILL.md'));
       assert.ok(normalizedSources.includes('standalone.txt'));
       assert.ok(normalizedSources.includes('.claude-plugin/plugin.json'));
       assert.ok(!normalizedSources.includes('missing.txt'));
@@ -318,6 +353,14 @@ function runTests() {
         operation.sourceRelativePath === path.join('.claude-plugin', 'plugin.json')
         && operation.destinationPath === path.join(homeDir, '.claude', 'plugin.json')
       )));
+      assert.ok(plan.operations.some(operation => (
+        operation.sourceRelativePath === path.join('rules', 'common', 'coding-style.md')
+        && operation.destinationPath === path.join(homeDir, '.claude', 'rules', 'ecc', 'common', 'coding-style.md')
+      )));
+      assert.ok(plan.operations.some(operation => (
+        operation.sourceRelativePath === path.join('skills', 'demo', 'SKILL.md')
+        && operation.destinationPath === path.join(homeDir, '.claude', 'skills', 'ecc', 'demo', 'SKILL.md')
+      )));
       assert.deepStrictEqual(plan.warnings, ['fixture warning']);
       assert.strictEqual(plan.statePreview.request.profile, 'minimal');
       assert.deepStrictEqual(plan.statePreview.request.includeComponents, ['capability:fixture']);
@@ -369,6 +412,8 @@ function runTests() {
       const applied = applyInstallPlan(plan);
 
       assert.strictEqual(applied.applied, true);
+      assert.ok(fs.existsSync(path.join(homeDir, '.claude', 'rules', 'ecc', 'common', 'coding-style.md')));
+      assert.ok(fs.existsSync(path.join(homeDir, '.claude', 'skills', 'ecc', 'demo', 'SKILL.md')));
       assert.ok(fs.existsSync(path.join(homeDir, '.claude', 'src', 'app.js')));
       assert.ok(fs.existsSync(path.join(homeDir, '.claude', 'standalone.txt')));
       assert.ok(fs.existsSync(path.join(homeDir, '.claude', 'plugin.json')));

tests/lib/install-targets.test.js

@@ -65,6 +65,42 @@ function runTests() {
     assert.strictEqual(statePath, path.join(homeDir, '.claude', 'ecc', 'install-state.json'));
   })) passed++; else failed++;
 
+  if (test('plans claude rules and skills under ECC-managed subdirectories', () => {
+    const repoRoot = path.join(__dirname, '..', '..');
+    const homeDir = '/Users/example';
+
+    const plan = planInstallTargetScaffold({
+      target: 'claude',
+      repoRoot,
+      homeDir,
+      modules: [
+        {
+          id: 'rules-core',
+          paths: ['rules'],
+        },
+        {
+          id: 'workflow-quality',
+          paths: ['skills/tdd-workflow'],
+        },
+      ],
+    });
+
+    assert.ok(
+      plan.operations.some(operation => (
+        normalizedRelativePath(operation.sourceRelativePath) === 'rules'
+        && operation.destinationPath === path.join(homeDir, '.claude', 'rules', 'ecc')
+      )),
+      'Should install bundled Claude rules under rules/ecc'
+    );
+    assert.ok(
+      plan.operations.some(operation => (
+        normalizedRelativePath(operation.sourceRelativePath) === 'skills/tdd-workflow'
+        && operation.destinationPath === path.join(homeDir, '.claude', 'skills', 'ecc', 'tdd-workflow')
+      )),
+      'Should install bundled Claude skills under skills/ecc'
+    );
+  })) passed++; else failed++;
+
   if (test('plans scaffold operations and flattens native target roots', () => {
     const repoRoot = path.join(__dirname, '..', '..');
     const projectRoot = '/workspace/app';

tests/lib/selective-install.test.js

@@ -576,10 +576,10 @@ function runTests() {
 
       const claudeRoot = path.join(homeDir, '.claude');
       // Security skill should be installed (from --with)
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'security-review', 'SKILL.md')),
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'ecc', 'security-review', 'SKILL.md')),
         'Should install security-review skill from --with');
       // Core profile modules should be installed
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'common', 'coding-style.md')),
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'ecc', 'common', 'coding-style.md')),
         'Should install core rules');
 
       // Install state should record include/exclude
@@ -615,12 +615,12 @@ function runTests() {
 
       const claudeRoot = path.join(homeDir, '.claude');
       // Orchestration skills should NOT be installed (from --without)
-      assert.ok(!fs.existsSync(path.join(claudeRoot, 'skills', 'dmux-workflows', 'SKILL.md')),
+      assert.ok(!fs.existsSync(path.join(claudeRoot, 'skills', 'ecc', 'dmux-workflows', 'SKILL.md')),
         'Should not install orchestration skills');
       // Developer profile base modules should be installed
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'common', 'coding-style.md')),
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'ecc', 'common', 'coding-style.md')),
         'Should install core rules');
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'tdd-workflow', 'SKILL.md')),
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'ecc', 'tdd-workflow', 'SKILL.md')),
         'Should install workflow skills');
 
       const statePath = path.join(claudeRoot, 'ecc', 'install-state.json');
@@ -653,10 +653,10 @@ function runTests() {
 
       const claudeRoot = path.join(homeDir, '.claude');
       // framework-language skill (from lang:typescript) should be installed
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'coding-standards', 'SKILL.md')),
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'ecc', 'coding-standards', 'SKILL.md')),
         'Should install framework-language skills');
       // Its dependencies should be installed
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'common', 'coding-style.md')),
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'ecc', 'common', 'coding-style.md')),
         'Should install dependency rules-core');
 
       const statePath = path.join(claudeRoot, 'ecc', 'install-state.json');

tests/scripts/install-apply.test.js

@@ -94,13 +94,13 @@ function runTests() {
       assert.strictEqual(result.code, 0, result.stderr);
 
       const claudeRoot = path.join(homeDir, '.claude');
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'common', 'coding-style.md')));
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'typescript', 'testing.md')));
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'ecc', 'common', 'coding-style.md')));
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'ecc', 'typescript', 'testing.md')));
       assert.ok(fs.existsSync(path.join(claudeRoot, 'commands', 'plan.md')));
       assert.ok(fs.existsSync(path.join(claudeRoot, 'scripts', 'hooks', 'session-end.js')));
       assert.ok(fs.existsSync(path.join(claudeRoot, 'scripts', 'lib', 'utils.js')));
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'tdd-workflow', 'SKILL.md')));
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'coding-standards', 'SKILL.md')));
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'ecc', 'tdd-workflow', 'SKILL.md')));
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'ecc', 'coding-standards', 'SKILL.md')));
       assert.ok(fs.existsSync(path.join(claudeRoot, 'plugin.json')));
 
       const statePath = path.join(homeDir, '.claude', 'ecc', 'install-state.json');
@@ -113,7 +113,7 @@ function runTests() {
       assert.ok(state.resolution.selectedModules.includes('framework-language'));
       assert.ok(
         state.operations.some(operation => (
-          operation.destinationPath === path.join(claudeRoot, 'rules', 'common', 'coding-style.md')
+          operation.destinationPath === path.join(claudeRoot, 'rules', 'ecc', 'common', 'coding-style.md')
         )),
         'Should record common rule file operation'
       );
@@ -299,7 +299,7 @@ function runTests() {
       assert.strictEqual(result.code, 0, result.stderr);
 
       const claudeRoot = path.join(homeDir, '.claude');
-      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'common', 'coding-style.md')));
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'ecc', 'common', 'coding-style.md')));
       assert.ok(fs.existsSync(path.join(claudeRoot, 'agents', 'architect.md')));
       assert.ok(fs.existsSync(path.join(claudeRoot, 'commands', 'plan.md')));
       assert.ok(fs.existsSync(path.join(claudeRoot, 'hooks', 'hooks.json')));
@@ -324,6 +324,32 @@ function runTests() {
     }
   })) passed++; else failed++;
 
+  if (test('preserves existing top-level Claude rules and skills during managed install', () => {
+    const homeDir = createTempDir('install-apply-home-');
+    const projectDir = createTempDir('install-apply-project-');
+
+    try {
+      const claudeRoot = path.join(homeDir, '.claude');
+      const userRulePath = path.join(claudeRoot, 'rules', 'common', 'coding-style.md');
+      const userSkillPath = path.join(claudeRoot, 'skills', 'tdd-workflow', 'SKILL.md');
+      fs.mkdirSync(path.dirname(userRulePath), { recursive: true });
+      fs.mkdirSync(path.dirname(userSkillPath), { recursive: true });
+      fs.writeFileSync(userRulePath, '# User custom rule\n');
+      fs.writeFileSync(userSkillPath, '# User custom skill\n');
+
+      const result = run(['--profile', 'core'], { cwd: projectDir, homeDir });
+      assert.strictEqual(result.code, 0, result.stderr);
+
+      assert.strictEqual(fs.readFileSync(userRulePath, 'utf8'), '# User custom rule\n');
+      assert.strictEqual(fs.readFileSync(userSkillPath, 'utf8'), '# User custom skill\n');
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'rules', 'ecc', 'common', 'coding-style.md')));
+      assert.ok(fs.existsSync(path.join(claudeRoot, 'skills', 'ecc', 'tdd-workflow', 'SKILL.md')));
+    } finally {
+      cleanup(homeDir);
+      cleanup(projectDir);
+    }
+  })) passed++; else failed++;
+
   if (test('installs antigravity manifest profiles while skipping only unsupported modules', () => {
     const homeDir = createTempDir('install-apply-home-');
     const projectDir = createTempDir('install-apply-project-');
@@ -727,8 +753,8 @@ function runTests() {
       const result = run(['--config', configPath], { cwd: projectDir, homeDir });
       assert.strictEqual(result.code, 0, result.stderr);
 
-      assert.ok(fs.existsSync(path.join(homeDir, '.claude', 'skills', 'security-review', 'SKILL.md')));
-      assert.ok(!fs.existsSync(path.join(homeDir, '.claude', 'skills', 'dmux-workflows', 'SKILL.md')));
+      assert.ok(fs.existsSync(path.join(homeDir, '.claude', 'skills', 'ecc', 'security-review', 'SKILL.md')));
+      assert.ok(!fs.existsSync(path.join(homeDir, '.claude', 'skills', 'ecc', 'dmux-workflows', 'SKILL.md')));
 
       const state = readJson(path.join(homeDir, '.claude', 'ecc', 'install-state.json'));
       assert.strictEqual(state.request.profile, 'developer');
@@ -759,8 +785,8 @@ function runTests() {
       const result = run([], { cwd: projectDir, homeDir });
       assert.strictEqual(result.code, 0, result.stderr);
 
-      assert.ok(fs.existsSync(path.join(homeDir, '.claude', 'skills', 'security-review', 'SKILL.md')));
-      assert.ok(!fs.existsSync(path.join(homeDir, '.claude', 'skills', 'dmux-workflows', 'SKILL.md')));
+      assert.ok(fs.existsSync(path.join(homeDir, '.claude', 'skills', 'ecc', 'security-review', 'SKILL.md')));
+      assert.ok(!fs.existsSync(path.join(homeDir, '.claude', 'skills', 'ecc', 'dmux-workflows', 'SKILL.md')));
 
       const state = readJson(path.join(homeDir, '.claude', 'ecc', 'install-state.json'));
       assert.strictEqual(state.request.profile, 'developer');

tests/scripts/install-readme-clarity.test.js

@@ -132,6 +132,10 @@ function runTests() {
       readme.includes('Start with `rules/common` plus one language or framework pack you actually use.'),
       'README should steer users away from copying every rules directory'
     );
+    assert.ok(
+      readme.includes('~/.claude/rules/ecc/'),
+      'README should steer plugin-path rules into an ECC-owned namespace'
+    );
   })) passed++; else failed++;
 
   console.log(`\nResults: Passed: ${passed}, Failed: ${failed}`);