diff --git a/plugins/llm-security/tests/scanners/ide-extension-scanner.test.mjs b/plugins/llm-security/tests/scanners/ide-extension-scanner.test.mjs
index 985043f..7439a56 100644
--- a/plugins/llm-security/tests/scanners/ide-extension-scanner.test.mjs
+++ b/plugins/llm-security/tests/scanners/ide-extension-scanner.test.mjs
@@ -3,7 +3,7 @@
 // Uses fixture trees under tests/fixtures/ide-extensions/ to simulate
 // real ~/.vscode/extensions/ layouts via rootsOverride injection.
 
-import { describe, it, beforeEach } from 'node:test';
+import { describe, it, before, beforeEach } from 'node:test';
 import assert from 'node:assert/strict';
 import { resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
@@ -490,3 +490,135 @@ describe('scanOneExtension JetBrains dispatch', () => {
     }
   });
 });
+
+// ---------------------------------------------------------------------------
+// JetBrains discovery + scan — full integration over root-jetbrains fixture
+// ---------------------------------------------------------------------------
+
+describe('JetBrains discovery + scan', () => {
+  const ROOT_JB = resolve(FIXTURES, 'root-jetbrains');
+  let env;
+  let allFindings;
+  const findingsById = new Map();
+
+  // Build jars from source/ trees once before the suite. The builder is
+  // idempotent + race-safe (atomic temp-then-rename, SHA-256 skip-if-match)
+  // so it is safe to run under node:test's parallel file execution.
+  before(async () => {
+    const { buildJetBrainsFixtures } = await import('../helpers/build-jetbrains-fixtures.mjs');
+    await buildJetBrainsFixtures({ fixtureRoot: ROOT_JB });
+
+    resetCounter();
+    env = await scan('all', { rootsOverride: [ROOT_JB], intellijOnly: true });
+    allFindings = env.extensions.flatMap(e => e.scanner_results.IDE?.findings || []);
+    for (const ext of env.extensions) {
+      findingsById.set(ext.id, ext.scanner_results.IDE?.findings || []);
+    }
+  });
+
+  it('discovers >= 8 JetBrains plugins (Fleet excluded)', () => {
+    assert.ok(
+      env.meta.extensions_discovered.jetbrains >= 8,
+      `expected >= 8 JB plugins, got ${env.meta.extensions_discovered.jetbrains}`,
+    );
+  });
+
+  it('includes every benign and adversarial IntelliJ fixture', () => {
+    for (const id of [
+      'com.example.benign',
+      'com.example.theme-with-code',
+      'com.example.broad-activation',
+      'com.example.premain',
+      'com.example.native-binary',
+      'com.example.depends-chain',
+      'com.intellij.jaba',
+    ]) {
+      assert.ok(
+        env.extensions.some(e => e.id === id),
+        `expected extension ${id} in discovery, got: ${env.extensions.map(e => e.id).join(', ')}`,
+      );
+    }
+  });
+
+  it('includes the Android Studio fixture (path divergence test)', () => {
+    assert.ok(
+      env.extensions.some(e => e.id === 'com.google.example'),
+      `expected com.google.example under AndroidStudio base, got: ${env.extensions.map(e => e.id).join(', ')}`,
+    );
+  });
+
+  it('excludes Fleet plugins (different plugin model)', () => {
+    assert.ok(
+      env.extensions.every(e => !e.location.includes('Fleet')),
+      `Fleet plugin leaked in: ${env.extensions.filter(e => e.location.includes('Fleet')).map(e => e.id).join(', ')}`,
+    );
+  });
+
+  it('all JB extensions routed through JetBrains path (type=jetbrains)', () => {
+    for (const ext of env.extensions) {
+      assert.equal(ext.type, 'jetbrains', `${ext.id} had type=${ext.type}`);
+    }
+  });
+
+  it('theme-with-code fixture triggers checkThemeWithCodeJB', () => {
+    const findings = findingsById.get('com.example.theme-with-code') || [];
+    assert.ok(
+      findings.some(f => f.title.includes('checkThemeWithCodeJB')),
+      `expected theme-with-code finding; got: ${findings.map(f => f.title).join(' | ')}`,
+    );
+  });
+
+  it('broad-activation fixture triggers checkBroadActivationJB', () => {
+    const findings = findingsById.get('com.example.broad-activation') || [];
+    assert.ok(
+      findings.some(f => f.title.includes('checkBroadActivationJB')),
+      `expected broad-activation finding; got: ${findings.map(f => f.title).join(' | ')}`,
+    );
+  });
+
+  it('premain fixture triggers checkPremainClassJB (HIGH)', () => {
+    const findings = findingsById.get('com.example.premain') || [];
+    const premain = findings.filter(f => f.title.includes('checkPremainClassJB'));
+    assert.ok(premain.length >= 1, `expected premain finding; got: ${findings.map(f => f.title).join(' | ')}`);
+    assert.equal(premain[0].severity, 'high');
+  });
+
+  it('native-binary fixture triggers checkNativeBinariesJB', () => {
+    const findings = findingsById.get('com.example.native-binary') || [];
+    assert.ok(
+      findings.some(f => f.title.includes('checkNativeBinariesJB')),
+      `expected native-binary finding; got: ${findings.map(f => f.title).join(' | ')}`,
+    );
+  });
+
+  it('depends-chain fixture triggers checkDependsChainJB', () => {
+    const findings = findingsById.get('com.example.depends-chain') || [];
+    assert.ok(
+      findings.some(f => f.title.includes('checkDependsChainJB')),
+      `expected depends-chain finding; got: ${findings.map(f => f.title).join(' | ')}`,
+    );
+  });
+
+  it('typosquat fixture (com.intellij.jaba) triggers checkTyposquatJB', () => {
+    const findings = findingsById.get('com.intellij.jaba') || [];
+    assert.ok(
+      findings.some(f => f.title.includes('checkTyposquatJB')),
+      `expected typosquat finding; got: ${findings.map(f => f.title).join(' | ')}`,
+    );
+  });
+
+  it('benign fixture produces no HIGH/CRITICAL JB findings', () => {
+    const findings = findingsById.get('com.example.benign') || [];
+    const highs = findings.filter(f => f.severity === 'high' || f.severity === 'critical');
+    assert.equal(
+      highs.length, 0,
+      `expected benign plugin to be clean; got: ${highs.map(f => f.title).join(' | ')}`,
+    );
+  });
+
+  it('all JB findings carry DS-IDE- prefix', () => {
+    for (const f of allFindings) {
+      assert.ok(f.id.startsWith('DS-IDE-'), `expected DS-IDE- prefix, got ${f.id}`);
+    }
+  });
+});