diff --git a/app/api.py b/app/api.py
index 49288a1..0a087f7 100644
--- a/app/api.py
+++ b/app/api.py
@@ -75,6 +75,7 @@
 _readme_summary_cache: dict[str, tuple[str, float]] = {}
 README_SUMMARY_CACHE_TTL_SEC = 86400.0
 from core.orchestrator import ScoutOrchestrator, MAX_QA_RETRIES
+from core.audit import audit_repository
 from core.agents.pathfinder import PathfinderAgent
 from core.terminal_manager import (
     SessionNotFoundError,
@@ -238,6 +239,12 @@ class ExportPdfRequest(BaseModel):
     content: str
 
 
+class AuditRepoRequest(BaseModel):
+    """Request body for a repository health audit."""
+
+    repo_url: str
+
+
 class ReAnalyzeRequest(BaseModel):
     """Request body for re-running phases 2+3 for a specific issue."""
 
@@ -1269,6 +1276,44 @@ def admin_memory_graph(
     return payload
 
 
+@app.post("/api/audit-repo")
+def audit_repo(
+    body: AuditRepoRequest,
+    request: Request,
+    user_ctx: UserContext = Depends(get_current_user),
+):
+    """
+    Run a deterministic health audit over an entire repository.
+
+    Clones the repo, scans for technical-debt markers and debug artifacts, and
+    returns a readiness score, pass/fail gate, severity breakdown, and findings.
+    No LLM calls are made.
+    """
+    repo_url = (body.repo_url or "").strip()
+    if not repo_url:
+        raise HTTPException(status_code=400, detail="repo_url is required")
+
+    try:
+        github_client = GitHubClient(token=_get_github_token_for_user(request))
+        owner, repo = github_client.parse_repo_url(repo_url)
+        repo_path = github_client.clone_repo(repo_url)
+        file_tree = github_client.get_file_tree(repo_path)
+        report = audit_repository(
+            repo_url=repo_url,
+            repo_full_name=f"{owner}/{repo}",
+            repo_path=repo_path,
+            file_tree=file_tree,
+        )
+        return _to_jsonable(report)
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=f"Invalid repository URL: {e}")
+    except RuntimeError as e:
+        raise HTTPException(status_code=502, detail=str(e))
+    except Exception as e:
+        logger.exception("Repository audit failed")
+        raise HTTPException(status_code=500, detail=str(e))
+
+
 @app.post("/api/export/pdf")
 def export_pdf(body: ExportPdfRequest):
     """Generate PDF from markdown content."""
diff --git a/core/audit/__init__.py b/core/audit/__init__.py
new file mode 100644
index 0000000..d35fd4e
--- /dev/null
+++ b/core/audit/__init__.py
@@ -0,0 +1,4 @@
+"""Repository health audit package."""
+from core.audit.repo_auditor import READINESS_THRESHOLD, audit_repository
+
+__all__ = ["audit_repository", "READINESS_THRESHOLD"]
diff --git a/core/audit/repo_auditor.py b/core/audit/repo_auditor.py
new file mode 100644
index 0000000..bd58c0f
--- /dev/null
+++ b/core/audit/repo_auditor.py
@@ -0,0 +1,257 @@
+"""
+Deterministic repository health audit.
+
+Scans a cloned repository for technical-debt markers and debug artifacts,
+then derives a readiness score (0-100) and a pass/fail gate. No LLM calls are
+made, so the audit is fast, reproducible, and free of API cost.
+"""
+from __future__ import annotations
+
+import re
+from datetime import datetime, timezone
+from pathlib import Path
+from typing import List, Optional, Tuple
+
+from core.schemas import (
+    AuditFinding,
+    AuditFileSummary,
+    AuditSeverityCounts,
+    RepoAuditReport,
+)
+
+READINESS_THRESHOLD = 70
+
+MAX_FILES = 4000
+MAX_FILE_BYTES = 1_500_000
+MAX_LINE_SCAN_LENGTH = 500
+MAX_FINDINGS = 400
+MAX_TOP_FILES = 10
+SNIPPET_LENGTH = 200
+
+SEVERITY_HIGH = "high"
+SEVERITY_MEDIUM = "medium"
+SEVERITY_LOW = "low"
+
+_SEVERITY_WEIGHTS = {SEVERITY_HIGH: 3.0, SEVERITY_MEDIUM: 1.0, SEVERITY_LOW: 0.4}
+_SCORE_SENSITIVITY = 6.0
+
+_HIGH_PATTERNS: List[Tuple[re.Pattern, str]] = [
+    (re.compile(r"\bFIXME\b", re.IGNORECASE), "FIXME"),
+    (re.compile(r"\bHACK\b", re.IGNORECASE), "HACK"),
+    (re.compile(r"\bXXX\b"), "XXX"),
+    (re.compile(r"\bBUG\b"), "BUG"),
+    (re.compile(r"\bSECURITY\b", re.IGNORECASE), "SECURITY"),
+]
+
+_MEDIUM_PATTERNS: List[Tuple[re.Pattern, str]] = [
+    (re.compile(r"\bTODO\b", re.IGNORECASE), "TODO"),
+    (re.compile(r"\bTBD\b", re.IGNORECASE), "TBD"),
+    (re.compile(r"\bWIP\b"), "WIP"),
+    (re.compile(r"\bDEPRECATED\b", re.IGNORECASE), "DEPRECATED"),
+]
+
+_LOW_PATTERNS: List[Tuple[re.Pattern, str]] = [
+    (re.compile(r"console\.(?:log|debug|trace)\s*\("), "console-log"),
+    (re.compile(r"\bdebugger\b\s*;?"), "debugger"),
+    (re.compile(r"\bpdb\.set_trace\s*\("), "pdb-set-trace"),
+    (re.compile(r"\bbreakpoint\s*\(\s*\)"), "breakpoint"),
+    (re.compile(r"\bbinding\.pry\b"), "binding-pry"),
+    (re.compile(r"\bvar_dump\s*\("), "var-dump"),
+]
+
+
+def _classify_line(line: str) -> Optional[Tuple[str, str, str]]:
+    """Return (severity, category, marker) for the highest-severity match, or None."""
+    for pattern, marker in _HIGH_PATTERNS:
+        if pattern.search(line):
+            return SEVERITY_HIGH, marker, marker
+    for pattern, marker in _MEDIUM_PATTERNS:
+        if pattern.search(line):
+            return SEVERITY_MEDIUM, marker, marker
+    for pattern, marker in _LOW_PATTERNS:
+        if pattern.search(line):
+            return SEVERITY_LOW, "debug-artifact", marker
+    return None
+
+
+def _compute_readiness(counts: AuditSeverityCounts, lines_scanned: int) -> int:
+    """Derive a 0-100 readiness score from weighted finding density per 1000 lines."""
+    weighted = (
+        counts.high * _SEVERITY_WEIGHTS[SEVERITY_HIGH]
+        + counts.medium * _SEVERITY_WEIGHTS[SEVERITY_MEDIUM]
+        + counts.low * _SEVERITY_WEIGHTS[SEVERITY_LOW]
+    )
+    per_kloc = (weighted / max(lines_scanned, 1)) * 1000
+    score = round(100 - per_kloc * _SCORE_SENSITIVITY)
+    return max(0, min(100, score))
+
+
+def _build_summary(report: RepoAuditReport) -> str:
+    gate = "PASSED" if report.gate_passed else "FAILED"
+    counts = report.severity_counts
+    return (
+        f"Gate {gate} — readiness {report.readiness_score}/100. "
+        f"Scanned {report.files_scanned} files ({report.lines_scanned} lines) and found "
+        f"{report.technical_debt} issues "
+        f"({counts.high} high, {counts.medium} medium, {counts.low} low)."
+    )
+
+
+def _build_markdown(report: RepoAuditReport) -> str:
+    counts = report.severity_counts
+    gate = "PASSED" if report.gate_passed else "FAILED"
+    lines: List[str] = [
+        f"# Repository Health Audit: {report.repo_full_name}",
+        "",
+        f"- **Readiness score:** {report.readiness_score}/100 (threshold {report.readiness_threshold})",
+        f"- **Gate:** {gate}",
+        f"- **Technical debt (total findings):** {report.technical_debt}",
+        f"- **Files scanned:** {report.files_scanned}",
+        f"- **Lines scanned:** {report.lines_scanned}",
+        f"- **Scanned at:** {report.scanned_at}",
+        "",
+        "## Severity breakdown",
+        "",
+        f"- High: {counts.high}",
+        f"- Medium: {counts.medium}",
+        f"- Low: {counts.low}",
+        "",
+    ]
+
+    if report.top_files:
+        lines.append("## Files with the most findings")
+        lines.append("")
+        lines.append("| File | Issues | High | Medium | Low |")
+        lines.append("| --- | ---: | ---: | ---: | ---: |")
+        for f in report.top_files:
+            lines.append(
+                f"| {f.file_path} | {f.issue_count} | {f.high} | {f.medium} | {f.low} |"
+            )
+        lines.append("")
+
+    if report.findings:
+        shown = report.findings[:50]
+        lines.append("## Sample findings")
+        lines.append("")
+        lines.append("| Severity | Category | Location | Snippet |")
+        lines.append("| --- | --- | --- | --- |")
+        for finding in shown:
+            snippet = finding.snippet.replace("|", "\\|")
+            location = f"{finding.file_path}:{finding.line_number}"
+            lines.append(
+                f"| {finding.severity} | {finding.category} | {location} | `{snippet}` |"
+            )
+        if report.findings_truncated or len(report.findings) > len(shown):
+            lines.append("")
+            lines.append(
+                f"_Showing {len(shown)} of {report.technical_debt} findings._"
+            )
+        lines.append("")
+
+    return "\n".join(lines)
+
+
+def audit_repository(
+    repo_url: str,
+    repo_full_name: str,
+    repo_path: Path,
+    file_tree: List[str],
+) -> RepoAuditReport:
+    """
+    Scan a cloned repository and produce a health audit report.
+
+    Args:
+        repo_url: Original repository URL.
+        repo_full_name: owner/repo identifier.
+        repo_path: Path to the locally cloned repository.
+        file_tree: Repo-relative file paths to scan (already filtered of binaries).
+
+    Returns:
+        A populated RepoAuditReport.
+    """
+    repo_path = Path(repo_path)
+    counts = AuditSeverityCounts()
+    findings: List[AuditFinding] = []
+    file_stats: dict[str, dict[str, int]] = {}
+    files_scanned = 0
+    lines_scanned = 0
+    findings_truncated = False
+
+    for rel_path in file_tree[:MAX_FILES]:
+        full_path = repo_path / rel_path
+        try:
+            if not full_path.is_file() or full_path.stat().st_size > MAX_FILE_BYTES:
+                continue
+        except OSError:
+            continue
+
+        try:
+            with open(full_path, "r", encoding="utf-8", errors="ignore") as handle:
+                files_scanned += 1
+                for line_number, raw_line in enumerate(handle, 1):
+                    lines_scanned += 1
+                    line = raw_line[:MAX_LINE_SCAN_LENGTH]
+                    classified = _classify_line(line)
+                    if classified is None:
+                        continue
+
+                    severity, category, marker = classified
+                    setattr(counts, severity, getattr(counts, severity) + 1)
+
+                    stats = file_stats.setdefault(
+                        rel_path, {SEVERITY_HIGH: 0, SEVERITY_MEDIUM: 0, SEVERITY_LOW: 0}
+                    )
+                    stats[severity] += 1
+
+                    if len(findings) < MAX_FINDINGS:
+                        findings.append(
+                            AuditFinding(
+                                file_path=rel_path,
+                                line_number=line_number,
+                                severity=severity,
+                                category=category,
+                                marker=marker,
+                                snippet=raw_line.strip()[:SNIPPET_LENGTH],
+                            )
+                        )
+                    else:
+                        findings_truncated = True
+        except OSError:
+            continue
+
+    technical_debt = counts.high + counts.medium + counts.low
+    readiness_score = _compute_readiness(counts, lines_scanned)
+
+    top_files = [
+        AuditFileSummary(
+            file_path=path,
+            issue_count=stats[SEVERITY_HIGH] + stats[SEVERITY_MEDIUM] + stats[SEVERITY_LOW],
+            high=stats[SEVERITY_HIGH],
+            medium=stats[SEVERITY_MEDIUM],
+            low=stats[SEVERITY_LOW],
+        )
+        for path, stats in file_stats.items()
+    ]
+    top_files.sort(key=lambda f: (f.issue_count, f.high, f.medium), reverse=True)
+    top_files = top_files[:MAX_TOP_FILES]
+
+    report = RepoAuditReport(
+        repo_url=repo_url,
+        repo_full_name=repo_full_name,
+        readiness_score=readiness_score,
+        gate_passed=readiness_score >= READINESS_THRESHOLD,
+        readiness_threshold=READINESS_THRESHOLD,
+        technical_debt=technical_debt,
+        files_scanned=files_scanned,
+        lines_scanned=lines_scanned,
+        severity_counts=counts,
+        top_files=top_files,
+        findings=findings,
+        findings_truncated=findings_truncated,
+        summary="",
+        report_markdown="",
+        scanned_at=datetime.now(timezone.utc).isoformat(),
+    )
+    report.summary = _build_summary(report)
+    report.report_markdown = _build_markdown(report)
+    return report
diff --git a/core/schemas.py b/core/schemas.py
index 3e3f3fa..3fa9b27 100644
--- a/core/schemas.py
+++ b/core/schemas.py
@@ -192,6 +192,53 @@ class TestingAgentOutput(BaseModel):
     iterations_used: int = Field(default=1, description="Number of QA iterations completed")
 
 
+# ==================== Repository Health Audit ====================
+
+class AuditFinding(BaseModel):
+    """A single technical-debt or debug-artifact finding in the codebase."""
+    file_path: str = Field(description="File path relative to repo root")
+    line_number: int = Field(ge=1, description="1-indexed line number of the finding")
+    severity: str = Field(description="Severity level: high, medium, or low")
+    category: str = Field(description="Finding category, e.g. FIXME, TODO, debug-artifact")
+    marker: str = Field(description="The matched marker keyword")
+    snippet: str = Field(description="Trimmed line content where the finding occurred")
+
+
+class AuditSeverityCounts(BaseModel):
+    """Aggregate finding counts grouped by severity."""
+    high: int = Field(default=0, ge=0, description="High severity count")
+    medium: int = Field(default=0, ge=0, description="Medium severity count")
+    low: int = Field(default=0, ge=0, description="Low severity count")
+
+
+class AuditFileSummary(BaseModel):
+    """Per-file rollup of findings, used to surface the noisiest files."""
+    file_path: str = Field(description="File path relative to repo root")
+    issue_count: int = Field(ge=0, description="Total findings in the file")
+    high: int = Field(default=0, ge=0, description="High severity count in file")
+    medium: int = Field(default=0, ge=0, description="Medium severity count in file")
+    low: int = Field(default=0, ge=0, description="Low severity count in file")
+
+
+class RepoAuditReport(BaseModel):
+    """Deterministic repository health audit report."""
+    repo_url: str = Field(description="Audited repository URL")
+    repo_full_name: str = Field(description="Repository full name (owner/repo)")
+    readiness_score: int = Field(ge=0, le=100, description="Overall readiness score (0-100)")
+    gate_passed: bool = Field(description="Whether the repo passes the readiness gate")
+    readiness_threshold: int = Field(ge=0, le=100, description="Score required to pass the gate")
+    technical_debt: int = Field(ge=0, description="Total number of findings across all severities")
+    files_scanned: int = Field(ge=0, description="Number of files scanned")
+    lines_scanned: int = Field(ge=0, description="Number of lines scanned")
+    severity_counts: AuditSeverityCounts = Field(description="Findings grouped by severity")
+    top_files: List[AuditFileSummary] = Field(default_factory=list, description="Files with the most findings")
+    findings: List[AuditFinding] = Field(default_factory=list, description="Individual findings (capped)")
+    findings_truncated: bool = Field(default=False, description="True when findings list was capped")
+    summary: str = Field(description="Human-readable summary of the audit")
+    report_markdown: str = Field(description="Full audit report rendered as Markdown")
+    scanned_at: str = Field(description="ISO-8601 UTC timestamp when the audit completed")
+
+
 # ==================== GitHub API Models ====================
 
 class GitHubIssue(BaseModel):
diff --git a/frontend/src/api.js b/frontend/src/api.js
index 360fbf8..d0d90f3 100644
--- a/frontend/src/api.js
+++ b/frontend/src/api.js
@@ -256,6 +256,17 @@ export async function reviewAndPushCode(owner, repo, payload) {
   return res.json();
 }
 
+export async function auditRepo(repoUrl) {
+  const res = await apiFetch(`/audit-repo`, {
+    method: 'POST',
+    body: JSON.stringify({ repo_url: repoUrl }),
+  }, TIMEOUTS.analysis)
+  if (!res.ok) {
+    throw new Error((await responseErrorDetail(res)) || 'Repository audit failed')
+  }
+  return res.json()
+}
+
 export async function exportPdf(content) {
   const res = await apiFetch(`/export/pdf`, {
     method: 'POST',
diff --git a/frontend/src/components/Dashboard.jsx b/frontend/src/components/Dashboard.jsx
index 573f850..efc2c6b 100644
--- a/frontend/src/components/Dashboard.jsx
+++ b/frontend/src/components/Dashboard.jsx
@@ -1,6 +1,6 @@
 import { useState, useEffect } from 'react'
 import { useSearchParams, useNavigate, Link } from 'react-router-dom'
-import { Search, Rocket, User, Github, ExternalLink, FolderKanban, Gauge, Brain } from 'lucide-react'
+import { Search, Rocket, User, Github, ExternalLink, FolderKanban, Gauge, Brain, ShieldCheck } from 'lucide-react'
 import { searchReposByTechStack, runAnalyze, createProject, getMe, feedbackRepoSelection } from '../api'
 import ScoutLogo from './ScoutLogo'
 import PathfinderSearchLoader from './PathfinderSearchLoader'
@@ -558,6 +558,17 @@ export default function Dashboard() {
           </div>
         )}
 
+        <div className="p-4 border-t border-app-border bg-app-surface/40 shrink-0">
+          <p className="text-[11px] uppercase tracking-wide text-app-muted mb-2">Tools</p>
+          <Link
+            to="/audit"
+            className="flex items-center gap-2 rounded-lg border border-app-border px-3 py-2 text-sm text-app-muted hover:text-app-text hover:border-primary-500/40 hover:bg-app-elevated transition-colors"
+          >
+            <ShieldCheck className="w-4 h-4" />
+            Repository Health Audit
+          </Link>
+        </div>
+
         {/* Profile Sidebar Footer */}
         <div className="p-4 border-t border-app-border bg-app-surface/50 shrink-0">
           <Link
diff --git a/frontend/src/main.jsx b/frontend/src/main.jsx
index f3128c7..d1c393f 100644
--- a/frontend/src/main.jsx
+++ b/frontend/src/main.jsx
@@ -16,6 +16,7 @@ import QaReport from './pages/QaReport.jsx'
 import EditorWindow from './pages/EditorWindow.jsx'
 import Profile from './pages/Profile.jsx'
 import Projects from './pages/Projects.jsx'
+import RepoAudit from './pages/RepoAudit.jsx'
 import AnalysisDashboard from './pages/AnalysisDashboard.jsx'
 import AdminDecisionTrace from './pages/AdminDecisionTrace.jsx'
 import AdminAgentMemory from './pages/AdminAgentMemory.jsx'
@@ -218,6 +219,7 @@ ReactDOM.createRoot(document.getElementById('root')).render(
         <Route path="/editor" element={<RequireAuth><EditorWindow /></RequireAuth>} />
         <Route path="/profile" element={<RequireAuth><Profile /></RequireAuth>} />
         <Route path="/projects" element={<RequireAuth><Projects /></RequireAuth>} />
+        <Route path="/audit" element={<RequireAuth><RepoAudit /></RequireAuth>} />
         <Route path="/admin/decision-trace" element={<RequireAdmin><AdminDecisionTrace /></RequireAdmin>} />
         <Route path="/admin/agent-memory" element={<RequireAdmin><AdminAgentMemory /></RequireAdmin>} />
       </Routes>
diff --git a/frontend/src/pages/RepoAudit.jsx b/frontend/src/pages/RepoAudit.jsx
new file mode 100644
index 0000000..78c1f88
--- /dev/null
+++ b/frontend/src/pages/RepoAudit.jsx
@@ -0,0 +1,288 @@
+import { useState } from 'react'
+import { Link } from 'react-router-dom'
+import {
+  ShieldCheck,
+  ShieldAlert,
+  ArrowLeft,
+  Search,
+  Download,
+  FileWarning,
+  FileCode2,
+  AlertTriangle,
+} from 'lucide-react'
+import { auditRepo, exportPdf } from '../api'
+import ScoutLogo from '../components/ScoutLogo'
+
+const SEVERITY_STYLES = {
+  high: 'bg-red-500/15 text-red-400 border-red-500/30',
+  medium: 'bg-amber-500/15 text-amber-400 border-amber-500/30',
+  low: 'bg-sky-500/15 text-sky-400 border-sky-500/30',
+}
+
+function scoreColor(score) {
+  if (score >= 70) return 'text-emerald-400'
+  if (score >= 40) return 'text-amber-400'
+  return 'text-red-400'
+}
+
+function StatCard({ label, value }) {
+  return (
+    <div className="rounded-xl border border-app-border bg-app-surface p-4">
+      <div className="text-[11px] font-semibold uppercase tracking-wide text-app-muted">{label}</div>
+      <div className="mt-1 text-2xl font-bold text-app-text">{value}</div>
+    </div>
+  )
+}
+
+export default function RepoAudit() {
+  const [repoUrl, setRepoUrl] = useState('')
+  const [loading, setLoading] = useState(false)
+  const [error, setError] = useState(null)
+  const [report, setReport] = useState(null)
+  const [downloading, setDownloading] = useState(false)
+
+  const handleScan = async () => {
+    const url = repoUrl.trim()
+    if (!url) return
+    setLoading(true)
+    setError(null)
+    setReport(null)
+    try {
+      const result = await auditRepo(url)
+      setReport(result)
+    } catch (err) {
+      setError(err.message || 'Audit failed. Please try again.')
+    } finally {
+      setLoading(false)
+    }
+  }
+
+  const handleDownloadPdf = async () => {
+    if (!report?.report_markdown) return
+    setDownloading(true)
+    try {
+      const blob = await exportPdf(report.report_markdown)
+      const objectUrl = URL.createObjectURL(blob)
+      const link = document.createElement('a')
+      link.href = objectUrl
+      const safeName = report.repo_full_name.replace(/[^a-z0-9]+/gi, '_')
+      link.download = `audit_${safeName}.pdf`
+      document.body.appendChild(link)
+      link.click()
+      link.remove()
+      URL.revokeObjectURL(objectUrl)
+    } catch (err) {
+      setError(err.message || 'PDF export failed.')
+    } finally {
+      setDownloading(false)
+    }
+  }
+
+  const counts = report?.severity_counts || { high: 0, medium: 0, low: 0 }
+
+  return (
+    <div className="min-h-screen bg-app-bg text-app-text">
+      <header className="sticky top-0 z-10 border-b border-app-border bg-app-bg/95 px-4 sm:px-8 py-4 backdrop-blur">
+        <div className="mx-auto flex max-w-5xl items-center justify-between gap-4">
+          <div className="flex items-center gap-3">
+            <ScoutLogo className="h-8 w-8 rounded-lg" />
+            <div>
+              <h1 className="text-lg font-semibold">Repository Health Audit</h1>
+              <p className="text-xs text-app-muted">Scan an entire codebase for technical debt and debug artifacts</p>
+            </div>
+          </div>
+          <Link
+            to="/dashboard"
+            className="inline-flex items-center gap-2 rounded-lg border border-app-border px-3 py-2 text-sm text-app-muted transition-colors hover:border-primary-500/40 hover:text-app-text"
+          >
+            <ArrowLeft className="h-4 w-4" />
+            Dashboard
+          </Link>
+        </div>
+      </header>
+
+      <main className="mx-auto max-w-5xl px-4 sm:px-8 py-8">
+        <div className="rounded-2xl border border-app-border bg-app-surface p-5">
+          <label htmlFor="repo-url" className="mb-2 block text-sm font-medium text-app-text">
+            GitHub repository URL
+          </label>
+          <div className="flex flex-col gap-3 sm:flex-row">
+            <input
+              id="repo-url"
+              type="text"
+              value={repoUrl}
+              onChange={(e) => setRepoUrl(e.target.value)}
+              onKeyDown={(e) => e.key === 'Enter' && handleScan()}
+              placeholder="https://github.com/owner/repo"
+              className="flex-1 rounded-lg border border-app-border bg-app-bg px-4 py-3 text-sm text-app-text outline-none focus:border-primary-500/50"
+            />
+            <button
+              type="button"
+              onClick={handleScan}
+              disabled={loading || !repoUrl.trim()}
+              className="inline-flex items-center justify-center gap-2 rounded-lg bg-accent-500 px-6 py-3 text-sm font-semibold text-[#0b0f14] transition-colors hover:bg-accent-600 disabled:cursor-not-allowed disabled:opacity-50"
+            >
+              {loading ? (
+                <>
+                  <svg className="h-4 w-4 animate-spin" viewBox="0 0 24 24">
+                    <circle className="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" strokeWidth="4" fill="none" />
+                    <path className="opacity-75" fill="currentColor" d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4z" />
+                  </svg>
+                  Scanning...
+                </>
+              ) : (
+                <>
+                  <Search className="h-4 w-4" />
+                  Scan repository
+                </>
+              )}
+            </button>
+          </div>
+          {error && (
+            <div className="mt-3 flex items-center gap-2 rounded-lg border border-red-500/30 bg-red-500/10 px-3 py-2 text-sm text-red-400">
+              <AlertTriangle className="h-4 w-4 shrink-0" />
+              {error}
+            </div>
+          )}
+        </div>
+
+        {report && (
+          <div className="mt-8 space-y-6">
+            <div
+              className={`flex flex-col gap-4 rounded-2xl border-2 p-6 sm:flex-row sm:items-center sm:justify-between ${
+                report.gate_passed ? 'border-emerald-500/40 bg-emerald-500/10' : 'border-red-500/40 bg-red-500/10'
+              }`}
+            >
+              <div className="flex items-center gap-4">
+                {report.gate_passed ? (
+                  <ShieldCheck className="h-12 w-12 text-emerald-400" />
+                ) : (
+                  <ShieldAlert className="h-12 w-12 text-red-400" />
+                )}
+                <div>
+                  <div className="text-sm text-app-muted">{report.repo_full_name}</div>
+                  <h2 className={`text-2xl font-bold ${report.gate_passed ? 'text-emerald-300' : 'text-red-300'}`}>
+                    Gate {report.gate_passed ? 'PASSED' : 'FAILED'}
+                  </h2>
+                  <p className="text-sm text-app-muted">{report.summary}</p>
+                </div>
+              </div>
+              <div className="text-left sm:text-right">
+                <div className={`text-5xl font-bold ${scoreColor(report.readiness_score)}`}>
+                  {report.readiness_score}
+                </div>
+                <div className="text-sm text-app-muted">/ 100 readiness</div>
+              </div>
+            </div>
+
+            <div className="grid grid-cols-2 gap-4 lg:grid-cols-4">
+              <StatCard label="Technical debt" value={report.technical_debt} />
+              <StatCard label="Files scanned" value={report.files_scanned} />
+              <StatCard label="Lines scanned" value={report.lines_scanned} />
+              <StatCard label="Threshold" value={`${report.readiness_threshold}/100`} />
+            </div>
+
+            <div className="grid grid-cols-1 gap-4 sm:grid-cols-3">
+              <div className="rounded-xl border border-red-500/30 bg-red-500/5 p-4">
+                <div className="flex items-center gap-2 text-red-400">
+                  <FileWarning className="h-4 w-4" />
+                  <span className="text-sm font-semibold">High severity</span>
+                </div>
+                <div className="mt-2 text-3xl font-bold text-app-text">{counts.high}</div>
+              </div>
+              <div className="rounded-xl border border-amber-500/30 bg-amber-500/5 p-4">
+                <div className="flex items-center gap-2 text-amber-400">
+                  <FileWarning className="h-4 w-4" />
+                  <span className="text-sm font-semibold">Medium severity</span>
+                </div>
+                <div className="mt-2 text-3xl font-bold text-app-text">{counts.medium}</div>
+              </div>
+              <div className="rounded-xl border border-sky-500/30 bg-sky-500/5 p-4">
+                <div className="flex items-center gap-2 text-sky-400">
+                  <FileCode2 className="h-4 w-4" />
+                  <span className="text-sm font-semibold">Low severity</span>
+                </div>
+                <div className="mt-2 text-3xl font-bold text-app-text">{counts.low}</div>
+              </div>
+            </div>
+
+            <div className="flex justify-end">
+              <button
+                type="button"
+                onClick={handleDownloadPdf}
+                disabled={downloading}
+                className="inline-flex items-center gap-2 rounded-lg border border-app-border px-4 py-2 text-sm font-medium text-app-text transition-colors hover:border-primary-500/40 hover:bg-app-elevated disabled:opacity-50"
+              >
+                <Download className="h-4 w-4" />
+                {downloading ? 'Preparing PDF...' : 'Download PDF report'}
+              </button>
+            </div>
+
+            {report.top_files?.length > 0 && (
+              <section>
+                <h3 className="mb-3 text-lg font-semibold">Files with the most findings</h3>
+                <div className="overflow-hidden rounded-xl border border-app-border">
+                  <table className="w-full text-sm">
+                    <thead className="bg-app-elevated/60 text-app-muted">
+                      <tr>
+                        <th className="px-4 py-2 text-left font-medium">File</th>
+                        <th className="px-4 py-2 text-right font-medium">Issues</th>
+                        <th className="px-4 py-2 text-right font-medium">High</th>
+                        <th className="px-4 py-2 text-right font-medium">Medium</th>
+                        <th className="px-4 py-2 text-right font-medium">Low</th>
+                      </tr>
+                    </thead>
+                    <tbody>
+                      {report.top_files.map((file) => (
+                        <tr key={file.file_path} className="border-t border-app-border">
+                          <td className="px-4 py-2 font-mono text-xs text-app-text break-all">{file.file_path}</td>
+                          <td className="px-4 py-2 text-right text-app-text">{file.issue_count}</td>
+                          <td className="px-4 py-2 text-right text-red-400">{file.high}</td>
+                          <td className="px-4 py-2 text-right text-amber-400">{file.medium}</td>
+                          <td className="px-4 py-2 text-right text-sky-400">{file.low}</td>
+                        </tr>
+                      ))}
+                    </tbody>
+                  </table>
+                </div>
+              </section>
+            )}
+
+            {report.findings?.length > 0 && (
+              <section>
+                <h3 className="mb-3 text-lg font-semibold">
+                  Findings
+                  {report.findings_truncated && (
+                    <span className="ml-2 text-sm font-normal text-app-muted">
+                      (showing first {report.findings.length} of {report.technical_debt})
+                    </span>
+                  )}
+                </h3>
+                <div className="space-y-2">
+                  {report.findings.map((finding, idx) => (
+                    <div
+                      key={`${finding.file_path}-${finding.line_number}-${idx}`}
+                      className="flex flex-col gap-1 rounded-lg border border-app-border bg-app-surface p-3 sm:flex-row sm:items-center sm:gap-3"
+                    >
+                      <span
+                        className={`inline-flex w-fit items-center rounded-full border px-2 py-0.5 text-xs font-medium ${
+                          SEVERITY_STYLES[finding.severity] || SEVERITY_STYLES.low
+                        }`}
+                      >
+                        {finding.severity} · {finding.category}
+                      </span>
+                      <span className="font-mono text-xs text-app-muted break-all">
+                        {finding.file_path}:{finding.line_number}
+                      </span>
+                      <code className="flex-1 truncate font-mono text-xs text-app-text">{finding.snippet}</code>
+                    </div>
+                  ))}
+                </div>
+              </section>
+            )}
+          </div>
+        )}
+      </main>
+    </div>
+  )
+}
diff --git a/tests/test_repo_auditor.py b/tests/test_repo_auditor.py
new file mode 100644
index 0000000..a00dd68
--- /dev/null
+++ b/tests/test_repo_auditor.py
@@ -0,0 +1,101 @@
+"""Tests for the deterministic repository health audit."""
+from pathlib import Path
+
+from core.audit.repo_auditor import READINESS_THRESHOLD, audit_repository
+
+
+def _write(repo: Path, rel: str, content: str) -> None:
+    path = repo / rel
+    path.parent.mkdir(parents=True, exist_ok=True)
+    path.write_text(content, encoding="utf-8")
+
+
+def test_clean_repo_passes_gate(tmp_path: Path):
+    _write(tmp_path, "main.py", "def add(a, b):\n    return a + b\n")
+    _write(tmp_path, "util.js", "export const ok = () => 42\n")
+    file_tree = ["main.py", "util.js"]
+
+    report = audit_repository(
+        repo_url="https://github.com/o/clean",
+        repo_full_name="o/clean",
+        repo_path=tmp_path,
+        file_tree=file_tree,
+    )
+
+    assert report.technical_debt == 0
+    assert report.readiness_score == 100
+    assert report.gate_passed is True
+    assert report.files_scanned == 2
+
+
+def test_markers_are_classified_by_severity(tmp_path: Path):
+    _write(
+        tmp_path,
+        "app.py",
+        "# TODO: refactor\n"
+        "x = 1  # FIXME broken\n"
+        "console.log('debug')\n",
+    )
+    file_tree = ["app.py"]
+
+    report = audit_repository(
+        repo_url="https://github.com/o/debt",
+        repo_full_name="o/debt",
+        repo_path=tmp_path,
+        file_tree=file_tree,
+    )
+
+    assert report.severity_counts.high == 1
+    assert report.severity_counts.medium == 1
+    assert report.severity_counts.low == 1
+    assert report.technical_debt == 3
+    assert report.top_files[0].file_path == "app.py"
+    assert report.top_files[0].issue_count == 3
+
+
+def test_highest_severity_wins_per_line(tmp_path: Path):
+    _write(tmp_path, "mix.py", "y = 2  # TODO and FIXME on one line\n")
+
+    report = audit_repository(
+        repo_url="https://github.com/o/mix",
+        repo_full_name="o/mix",
+        repo_path=tmp_path,
+        file_tree=["mix.py"],
+    )
+
+    assert report.severity_counts.high == 1
+    assert report.severity_counts.medium == 0
+    assert report.technical_debt == 1
+
+
+def test_high_debt_density_fails_gate_and_builds_report(tmp_path: Path):
+    body = "".join(f"# FIXME issue {i}\n" for i in range(40))
+    _write(tmp_path, "legacy.py", body)
+
+    report = audit_repository(
+        repo_url="https://github.com/o/legacy",
+        repo_full_name="o/legacy",
+        repo_path=tmp_path,
+        file_tree=["legacy.py"],
+    )
+
+    assert report.severity_counts.high == 40
+    assert report.readiness_score < READINESS_THRESHOLD
+    assert report.gate_passed is False
+    assert "Repository Health Audit" in report.report_markdown
+    assert report.summary
+
+
+def test_missing_files_are_skipped(tmp_path: Path):
+    _write(tmp_path, "present.py", "# TODO only here\n")
+    file_tree = ["present.py", "does_not_exist.py"]
+
+    report = audit_repository(
+        repo_url="https://github.com/o/partial",
+        repo_full_name="o/partial",
+        repo_path=tmp_path,
+        file_tree=file_tree,
+    )
+
+    assert report.files_scanned == 1
+    assert report.severity_counts.medium == 1