diff --git a/test/helpers/touchfiles.ts b/test/helpers/touchfiles.ts
index 995648a1..41436d6a 100644
--- a/test/helpers/touchfiles.ts
+++ b/test/helpers/touchfiles.ts
@@ -90,6 +90,10 @@ export const E2E_TOUCHFILES: Record<string, string[]> = {
 
   // gstack-upgrade
   'gstack-upgrade-happy-path': ['gstack-upgrade/**'],
+
+  // Debug escalation
+  'qa-debug-prompt-logic': ['qa/**', 'debug/**'],
+  'qa-debug-escalation':   ['qa/**', 'debug/**', 'browse/src/**'],
 };
 
 /**
@@ -123,6 +127,9 @@ export const LLM_JUDGE_TOUCHFILES: Record<string, string[]> = {
   'retro/SKILL.md instructions':          ['retro/SKILL.md', 'retro/SKILL.md.tmpl'],
   'qa-only/SKILL.md workflow':            ['qa-only/SKILL.md', 'qa-only/SKILL.md.tmpl'],
   'gstack-upgrade/SKILL.md upgrade flow': ['gstack-upgrade/SKILL.md', 'gstack-upgrade/SKILL.md.tmpl'],
+
+  // Debug escalation
+  'qa/SKILL.md debug escalation': ['qa/SKILL.md', 'qa/SKILL.md.tmpl', 'debug/SKILL.md', 'debug/SKILL.md.tmpl'],
 };
 
 /**
diff --git a/test/skill-e2e.test.ts b/test/skill-e2e.test.ts
index 13539278..f02b6b6f 100644
--- a/test/skill-e2e.test.ts
+++ b/test/skill-e2e.test.ts
@@ -2841,6 +2841,67 @@ Output the diagram directly.`,
   }, 180_000);
 });
 
+// --- Debug escalation E2E tests ---
+
+describeIfSelected('Debug escalation', ['qa-debug-prompt-logic', 'qa-debug-escalation'], () => {
+  // Test A: Prompt-level deterministic — verify the template produces correct escalation behavior
+  testIfSelected('qa-debug-prompt-logic', async () => {
+    const result = await runSkillTest({
+      prompt: `You are in Phase 8g of the /qa workflow. The following has happened:
+- ISSUE-007: "Submit button does nothing on checkout page"
+  - Severity: critical
+  - URL: http://localhost:3000/checkout
+  - Fix attempt 1: Added click handler to button → caused JS error on payment page (reverted)
+  - Fix attempt 2: Fixed form action attribute → broke form validation (reverted)
+  - Files investigated: src/components/Checkout.tsx, src/pages/checkout.ts
+  - Console errors: "TypeError: Cannot read property 'submit' of null"
+
+Read qa/SKILL.md and follow Phase 8g exactly. Show the Agent prompt you would use to spawn the debug sub-agent. Do NOT actually spawn the agent — just output the prompt you would use.`,
+      maxTurns: 10,
+    });
+
+    recordE2E('qa-debug-prompt-logic', 'Debug escalation', result);
+
+    // Verify the output contains a well-formed structured brief
+    const output = result.output ?? '';
+    const hasIssueId = /ISSUE-007/i.test(output);
+    const hasSymptom = /submit.*button|does nothing|checkout/i.test(output);
+    const hasRepro = /localhost.*3000|checkout/i.test(output);
+    const hasFailedAttempts = /fix attempt|click handler|form action/i.test(output);
+    const hasFiles = /Checkout\.tsx|checkout\.ts/i.test(output);
+    const hasDebugSkillRef = /debug\/SKILL\.md/i.test(output);
+
+    console.log(`Has Issue ID: ${hasIssueId}`);
+    console.log(`Has Symptom: ${hasSymptom}`);
+    console.log(`Has Repro: ${hasRepro}`);
+    console.log(`Has Failed Attempts: ${hasFailedAttempts}`);
+    console.log(`Has Files: ${hasFiles}`);
+    console.log(`Has Debug Skill Ref: ${hasDebugSkillRef}`);
+
+    // The output should contain all the structured handoff fields
+    expect(hasIssueId).toBe(true);
+    expect(hasSymptom).toBe(true);
+    expect(hasFailedAttempts).toBe(true);
+    expect(hasDebugSkillRef).toBe(true);
+  }, 120_000);
+
+  // Test B: Full E2E with planted regression
+  // This test requires a fixture app with a deliberately hard-to-fix bug.
+  // The bug should resist at least 2 fix attempts to trigger escalation.
+  // TODO: Create fixture at browse/test/fixtures/qa-eval-debug-escalation/
+  testIfSelected('qa-debug-escalation', async () => {
+    // Skip until fixture is created — this is a placeholder for the full flow
+    console.log('SKIP: qa-debug-escalation — fixture not yet created');
+    console.log('TODO: Create browse/test/fixtures/qa-eval-debug-escalation/ with a deliberately hard-to-fix bug');
+    // When implemented, this test should:
+    // 1. Start test server serving the fixture
+    // 2. Run /qa against it
+    // 3. Verify fix attempts are made and reverted
+    // 4. Verify Phase 8g triggers (Agent tool call appears in transcript)
+    // 5. Verify debug report appears in QA output
+  }, 300_000);
+});
+
 // Module-level afterAll — finalize eval collector after all tests complete
 afterAll(async () => {
   if (evalCollector) {
diff --git a/test/skill-llm-eval.test.ts b/test/skill-llm-eval.test.ts
index 528d5115..058f52a0 100644
--- a/test/skill-llm-eval.test.ts
+++ b/test/skill-llm-eval.test.ts
@@ -668,6 +668,23 @@ describeIfSelected('Other skill evals', [
   }, 30_000);
 });
 
+// Block 5: Debug escalation
+describeIfSelected('Debug escalation evals', [
+  'qa/SKILL.md debug escalation',
+], () => {
+  testIfSelected('qa/SKILL.md debug escalation', async () => {
+    await runWorkflowJudge({
+      testName: 'qa/SKILL.md debug escalation',
+      suite: 'Debug escalation evals',
+      skillPath: 'qa/SKILL.md',
+      startMarker: '### 8g. Debug Escalation',
+      endMarker: '## Phase 9: Final QA',
+      judgeContext: 'a debug sub-agent escalation workflow within a QA fix loop',
+      judgeGoal: 'when and how to spawn a debug sub-agent for bugs that resisted multiple fix attempts, including structured bug brief format (issue ID, symptom, reproduction, failed fix attempts, files), result handling for all four statuses (DONE, DONE_WITH_CONCERNS, BLOCKED, agent failure), working tree cleanup, and sequential processing',
+    });
+  }, 30_000);
+});
+
 // Module-level afterAll — finalize eval collector after all tests complete
 afterAll(async () => {
   if (evalCollector) {
diff --git a/test/skill-validation.test.ts b/test/skill-validation.test.ts
index e63a4b67..f02c27b6 100644
--- a/test/skill-validation.test.ts
+++ b/test/skill-validation.test.ts
@@ -620,6 +620,74 @@ describe('debug skill structure', () => {
                           'DEBUG REPORT', '3-strike', 'BLOCKED']) {
     test(`contains ${section}`, () => expect(content).toContain(section));
   }
+
+  test('has browse setup for visual reproduction', () => {
+    expect(content).toContain('Visual reproduction');
+    expect(content).toContain('$B goto');
+    expect(content).toContain('$B screenshot');
+  });
+
+  test('has visual verification in Phase 5', () => {
+    expect(content).toContain('Visual verification');
+    expect(content).toContain('debug-ISSUE-NNN-fixed');
+  });
+});
+
+// --- Debug sub-agent escalation validation ---
+
+describe('Debug sub-agent escalation', () => {
+  test('qa/SKILL.md has Agent in allowed-tools', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'qa', 'SKILL.md'), 'utf-8');
+    // Check frontmatter allowed-tools section contains Agent
+    const frontmatter = content.split('---')[1];
+    expect(frontmatter).toContain('Agent');
+  });
+
+  test('qa/SKILL.md has Phase 8g Debug Escalation', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'qa', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('8g. Debug Escalation');
+    expect(content).toContain('reverted at least twice');
+    expect(content).toContain('Bug Brief');
+    expect(content).toContain('debug/SKILL.md');
+  });
+
+  test('qa/SKILL.md has structured handoff in debug prompt', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'qa', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('Issue ID');
+    expect(content).toContain('Symptom');
+    expect(content).toContain('Reproduction');
+    expect(content).toContain('Failed fix attempts');
+    expect(content).toContain('Files investigated');
+  });
+
+  test('qa/SKILL.md has all four agent result handlers', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'qa', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('DONE status');
+    expect(content).toContain('DONE_WITH_CONCERNS');
+    expect(content).toContain('git checkout .');
+    expect(content).toContain('deferred (debug unavailable)');
+  });
+
+  test('qa/SKILL.md has debug escalation summary in Phase 10', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'qa', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('DEBUG ESCALATION');
+    expect(content).toContain('Issues escalated');
+    expect(content).toContain('Per-issue details');
+  });
+
+  test('review/SKILL.md has Step 5.7 pre-existing bug detection', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'review', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('5.7: Pre-existing bug detection');
+    expect(content).toContain('/debug');
+    expect(content).toContain('pre-existing issue');
+  });
+
+  test('ship/SKILL.md has reverted QA commit detection', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'ship', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('Reverted QA fix detection');
+    expect(content).toContain('revert.*fix(qa)');
+    expect(content).toContain('/debug');
+  });
 });
 
 // --- Contributor mode preamble structure validation ---
diff --git a/test/touchfiles.test.ts b/test/touchfiles.test.ts
index 48613d64..84a4a5a8 100644
--- a/test/touchfiles.test.ts
+++ b/test/touchfiles.test.ts
@@ -122,7 +122,8 @@ describe('selectTests', () => {
     const result = selectTests(['qa/SKILL.md'], LLM_JUDGE_TOUCHFILES);
     expect(result.selected).toContain('qa/SKILL.md workflow');
     expect(result.selected).toContain('qa/SKILL.md health rubric');
-    expect(result.selected.length).toBe(2);
+    expect(result.selected).toContain('qa/SKILL.md debug escalation');
+    expect(result.selected.length).toBe(3);
   });
 
   test('SKILL.md.tmpl root template only selects root-dependent tests', () => {