diff --git a/README.md b/README.md
index 3ef6fa5..00e3bcf 100644
--- a/README.md
+++ b/README.md
@@ -51,6 +51,11 @@ scripts from the existing `Seg/` workspace are mapped to web jobs. MMSeg
 vendored internals, docs, build outputs, converters, and config templates are
 classified as supporting artifacts rather than direct web actions.
 
+The same panel can run `POST /api/acceptance/smoke`, a lightweight live smoke
+that creates an upload dataset, uploads a label, downloads it through the
+artifact API, runs a mock job, checks SSE log streaming, and executes one
+legacy image/label overlay job on tiny generated PNGs.
+
 ## Weight Sync
 
 The current workspace contains tens of GB of pretrained and trained weights.
@@ -107,4 +112,5 @@ PYTHONPATH=backend conda run -n seg_smp python scripts/run_agents.py --build
 
 The validation agent checks catalog coverage, the new `seg_smp` env, GPU
 visibility, no-weight Git safety, backend tests, frontend build, and live
-backend/frontend endpoints when the services are running.
+backend/frontend endpoints when the services are running. With live validation
+enabled it also runs the lightweight acceptance smoke above.
diff --git a/backend/app/acceptance.py b/backend/app/acceptance.py
new file mode 100644
index 0000000..b600589
--- /dev/null
+++ b/backend/app/acceptance.py
@@ -0,0 +1,201 @@
+from __future__ import annotations
+
+import json
+import time
+import uuid
+import urllib.error
+import urllib.request
+from pathlib import Path
+from typing import Any
+
+from .config import settings
+
+
+def _request_json(method: str, url: str, payload: dict[str, Any] | None = None, timeout: int = 10) -> dict[str, Any]:
+    data = None
+    headers = {"Accept": "application/json"}
+    if payload is not None:
+        data = json.dumps(payload, ensure_ascii=False).encode("utf-8")
+        headers["Content-Type"] = "application/json"
+    request = urllib.request.Request(url, data=data, headers=headers, method=method)
+    try:
+        with urllib.request.urlopen(request, timeout=timeout) as response:
+            body = response.read().decode("utf-8", errors="replace")
+            return {"passed": 200 <= response.status < 300, "status": response.status, "body": body, "json": json.loads(body) if body else None}
+    except urllib.error.HTTPError as exc:
+        body = exc.read().decode("utf-8", errors="replace")
+        return {"passed": False, "status": exc.code, "body": body}
+    except Exception as exc:
+        return {"passed": False, "error": str(exc)}
+
+
+def _request_text(url: str, timeout: int = 10) -> dict[str, Any]:
+    try:
+        with urllib.request.urlopen(url, timeout=timeout) as response:
+            body = response.read().decode("utf-8", errors="replace")
+            return {"passed": 200 <= response.status < 300, "status": response.status, "body": body}
+    except Exception as exc:
+        return {"passed": False, "error": str(exc)}
+
+
+def _post_multipart(url: str, field: str, filename: str, content: bytes, content_type: str = "text/plain", timeout: int = 10) -> dict[str, Any]:
+    boundary = f"----SegAcceptance{uuid.uuid4().hex}"
+    body = b"".join(
+        [
+            f"--{boundary}\r\n".encode(),
+            f'Content-Disposition: form-data; name="{field}"; filename="{filename}"\r\n'.encode(),
+            f"Content-Type: {content_type}\r\n\r\n".encode(),
+            content,
+            f"\r\n--{boundary}--\r\n".encode(),
+        ]
+    )
+    request = urllib.request.Request(
+        url,
+        data=body,
+        method="POST",
+        headers={"Content-Type": f"multipart/form-data; boundary={boundary}", "Accept": "application/json"},
+    )
+    try:
+        with urllib.request.urlopen(request, timeout=timeout) as response:
+            text = response.read().decode("utf-8", errors="replace")
+            return {"passed": 200 <= response.status < 300, "status": response.status, "body": text, "json": json.loads(text) if text else None}
+    except urllib.error.HTTPError as exc:
+        text = exc.read().decode("utf-8", errors="replace")
+        return {"passed": False, "status": exc.code, "body": text}
+    except Exception as exc:
+        return {"passed": False, "error": str(exc)}
+
+
+def _poll_job(base_url: str, job_id: str, timeout: int = 90) -> dict[str, Any]:
+    deadline = time.time() + timeout
+    last = None
+    while time.time() < deadline:
+        result = _request_json("GET", f"{base_url}/api/jobs/{job_id}", timeout=10)
+        last = result
+        job = result.get("json") if result.get("passed") else None
+        if job and job.get("status") in {"success", "failed", "cancelled"}:
+            return {"passed": job.get("status") == "success", "job": job}
+        time.sleep(1)
+    return {"passed": False, "error": "job timed out", "last": last}
+
+
+def _create_job_and_wait(base_url: str, task_type: str, params: dict[str, Any], timeout: int = 90) -> dict[str, Any]:
+    created = _request_json("POST", f"{base_url}/api/jobs", {"type": task_type, "params": params}, timeout=10)
+    if not created.get("passed") or not created.get("json"):
+        return {"passed": False, "created": created}
+    job_id = created["json"]["id"]
+    polled = _poll_job(base_url, job_id, timeout=timeout)
+    events = _request_text(f"{base_url}/api/jobs/{job_id}/events", timeout=10)
+    return {"passed": polled["passed"], "created": created["json"], "polled": polled, "events": events}
+
+
+def _create_job_with_retry(base_url: str, task_type: str, params: dict[str, Any], attempts: int = 2, timeout: int = 90) -> dict[str, Any]:
+    results = []
+    for _ in range(attempts):
+        result = _create_job_and_wait(base_url, task_type, params, timeout=timeout)
+        results.append(result)
+        if result.get("passed"):
+            return {"passed": True, "attempts": results}
+        time.sleep(1)
+    return {"passed": False, "attempts": results}
+
+
+def _write_acceptance_images(root: Path) -> tuple[Path, Path, Path]:
+    import cv2
+    import numpy as np
+
+    image_dir = root / "images"
+    label_dir = root / "labels"
+    result_dir = root / "stacked"
+    image_dir.mkdir(parents=True, exist_ok=True)
+    label_dir.mkdir(parents=True, exist_ok=True)
+    result_dir.mkdir(parents=True, exist_ok=True)
+
+    image = np.zeros((16, 16, 3), dtype=np.uint8)
+    image[:, :, 1] = 180
+    label = np.zeros((16, 16, 3), dtype=np.uint8)
+    label[4:12, 4:12, 2] = 255
+    image_path = image_dir / "sample.png"
+    label_path = label_dir / "sample.png"
+    cv2.imwrite(str(image_path), image)
+    cv2.imwrite(str(label_path), label)
+    return image_path, label_path, result_dir
+
+
+def latest_acceptance_report() -> dict[str, Any]:
+    path = settings.project_root / "var" / "acceptance" / "latest.json"
+    if not path.exists():
+        return {"available": False, "path": str(path)}
+    return json.loads(path.read_text(encoding="utf-8"))
+
+
+def run_live_acceptance(base_url: str = "http://127.0.0.1:8010") -> dict[str, Any]:
+    """Run a lightweight end-to-end smoke against the live API and job runner."""
+    acceptance_root = settings.project_root / "var" / "acceptance"
+    run_id = uuid.uuid4().hex[:8]
+    fixture_root = acceptance_root / f"run_{run_id}"
+    fixture_root.mkdir(parents=True, exist_ok=True)
+
+    checks: list[dict[str, Any]] = []
+
+    dataset_name = f"acceptance_{run_id}"
+    created_dataset = _request_json("POST", f"{base_url}/api/datasets", {"name": dataset_name, "description": "acceptance smoke"}, timeout=10)
+    checks.append({"name": "create_dataset_api", "passed": created_dataset.get("passed", False), "detail": created_dataset})
+
+    upload = _post_multipart(
+        f"{base_url}/api/datasets/{dataset_name}/upload/labels",
+        "files",
+        "label 01.txt",
+        b"0 0.5 0.5 0.25 0.25\n",
+        "text/plain",
+        timeout=10,
+    )
+    checks.append({"name": "upload_label_api", "passed": upload.get("passed", False), "detail": upload})
+
+    artifact_ok = False
+    artifact_detail: dict[str, Any] = {"skipped": True}
+    try:
+        relative_path = upload["json"]["saved"][0]["relative_path"]
+        artifact_detail = _request_text(f"{base_url}/api/artifacts/{relative_path}", timeout=10)
+        artifact_ok = artifact_detail.get("passed", False) and "0 0.5" in artifact_detail.get("body", "")
+    except Exception as exc:
+        artifact_detail = {"error": str(exc)}
+    checks.append({"name": "artifact_api_for_uploaded_label", "passed": artifact_ok, "detail": artifact_detail})
+
+    mock = _create_job_and_wait(base_url, "mock.echo", {"message": f"acceptance {run_id}"}, timeout=45)
+    mock_log = mock.get("polled", {}).get("job", {}).get("log_tail", "")
+    checks.append({"name": "mock_job_runner", "passed": mock.get("passed", False) and f"acceptance {run_id}" in mock_log, "detail": mock})
+
+    image_path, label_path, result_dir = _write_acceptance_images(fixture_root)
+    stack = _create_job_with_retry(
+        base_url,
+        "dataset.stack_single",
+        {
+            "image_path": str(image_path),
+            "label_path": str(label_path),
+            "result_dir": str(result_dir),
+            "alpha": 0.35,
+        },
+        attempts=2,
+        timeout=90,
+    )
+    output_path = result_dir / "sample.png"
+    checks.append(
+        {
+            "name": "legacy_stack_job_runner",
+            "passed": stack.get("passed", False) and output_path.exists() and output_path.stat().st_size > 0,
+            "detail": {**stack, "output_path": str(output_path), "output_exists": output_path.exists()},
+        }
+    )
+
+    report = {
+        "available": True,
+        "run_id": run_id,
+        "base_url": base_url,
+        "passed": all(item["passed"] for item in checks),
+        "checks": checks,
+        "created_at": time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime()),
+    }
+    latest = acceptance_root / "latest.json"
+    latest.write_text(json.dumps(report, ensure_ascii=False, indent=2), encoding="utf-8")
+    return report
diff --git a/backend/app/agents/validation_agent.py b/backend/app/agents/validation_agent.py
index 2984160..6db2363 100644
--- a/backend/app/agents/validation_agent.py
+++ b/backend/app/agents/validation_agent.py
@@ -8,6 +8,7 @@ import urllib.error
 import urllib.request
 from pathlib import Path
 
+from ..acceptance import run_live_acceptance
 from ..catalog import get_catalog
 from ..config import settings
 from ..coverage import get_coverage_report
@@ -84,6 +85,9 @@ def validate_project(run_build: bool = False) -> dict:
         checks.append({"name": "live_dataset_api", "passed": datasets["passed"] and datasets.get("body", "").lstrip().startswith("["), "detail": datasets})
         checks.append({"name": "live_coverage_api", "passed": live_coverage["passed"] and '"task_build_passed":true' in live_coverage.get("body", "").replace(" ", ""), "detail": live_coverage})
         checks.append({"name": "live_frontend_index", "passed": frontend["passed"] and "Seg Data Server" in frontend.get("body", ""), "detail": frontend})
+        if os.getenv("SEG_VALIDATE_ACCEPTANCE", "1") == "1":
+            acceptance = run_live_acceptance(backend_url)
+            checks.append({"name": "live_acceptance_smoke", "passed": acceptance["passed"], "detail": acceptance})
 
     if run_build:
         tests = _run(["conda", "run", "-n", settings.backend_conda_env, "python", "-m", "pytest", "-q"], cwd=settings.project_root, timeout=120)
diff --git a/backend/app/main.py b/backend/app/main.py
index 7c60b06..c362717 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -9,6 +9,7 @@ from fastapi.middleware.cors import CORSMiddleware
 from fastapi.responses import FileResponse, StreamingResponse
 
 from . import db
+from .acceptance import latest_acceptance_report, run_live_acceptance
 from .catalog import get_catalog
 from .config import settings
 from .coverage import get_coverage_report
@@ -69,6 +70,16 @@ def api_coverage() -> dict:
     return get_coverage_report()
 
 
+@app.get("/api/acceptance/latest")
+def api_acceptance_latest() -> dict:
+    return latest_acceptance_report()
+
+
+@app.post("/api/acceptance/smoke")
+def api_acceptance_smoke(base_url: str = "http://127.0.0.1:8010") -> dict:
+    return run_live_acceptance(base_url)
+
+
 @app.get("/api/datasets")
 def api_datasets() -> list[dict]:
     return list_uploaded_datasets()
@@ -163,7 +174,11 @@ def api_results() -> list[dict]:
 def api_artifact(artifact_path: str):
     candidate = Path(artifact_path)
     if not candidate.is_absolute():
-        candidate = settings.source_root / candidate
+        first_part = candidate.parts[0] if candidate.parts else ""
+        if first_part in {"var", "weights"}:
+            candidate = settings.project_root / candidate
+        else:
+            candidate = settings.source_root / candidate
     try:
         resolved = candidate.resolve()
         allowed = False
diff --git a/backend/tests/test_artifacts.py b/backend/tests/test_artifacts.py
new file mode 100644
index 0000000..28e0483
--- /dev/null
+++ b/backend/tests/test_artifacts.py
@@ -0,0 +1,34 @@
+from pathlib import Path
+
+from fastapi.testclient import TestClient
+
+from app.main import app
+
+
+def test_project_var_artifact_path_is_served(tmp_path, monkeypatch):
+    from app import main
+
+    project_root = tmp_path / "project"
+    source_root = tmp_path / "source"
+    artifact = project_root / "var" / "uploads" / "datasets" / "case" / "labels" / "label.txt"
+    artifact.parent.mkdir(parents=True)
+    artifact.write_text("ok", encoding="utf-8")
+    source_root.mkdir()
+
+    original = main.settings
+    patched = type(original)(
+        project_root=project_root,
+        source_root=source_root,
+        db_path=original.db_path,
+        log_dir=original.log_dir,
+        weights_root=original.weights_root,
+        task_conda_env=original.task_conda_env,
+        backend_conda_env=original.backend_conda_env,
+        weight_mode=original.weight_mode,
+        enable_shell_tasks=original.enable_shell_tasks,
+    )
+    monkeypatch.setattr(main, "settings", patched)
+
+    response = TestClient(app).get("/api/artifacts/var/uploads/datasets/case/labels/label.txt")
+    assert response.status_code == 200
+    assert response.text == "ok"
diff --git a/frontend/src/main.tsx b/frontend/src/main.tsx
index 1334b5b..3f4b7e1 100644
--- a/frontend/src/main.tsx
+++ b/frontend/src/main.tsx
@@ -72,6 +72,14 @@ type CoveragePayload = {
   task_build_checks: Array<{ task: string; passed: boolean; script_exists?: boolean; error?: string }>;
 };
 
+type AcceptancePayload = {
+  available?: boolean;
+  passed?: boolean;
+  run_id?: string;
+  created_at?: string;
+  checks?: Array<{ name: string; passed: boolean }>;
+};
+
 type GpuPayload = {
   available: boolean;
   gpus: Array<{
@@ -152,17 +160,19 @@ function useData() {
   const [results, setResults] = useState<ResultItem[]>([]);
   const [datasets, setDatasets] = useState<UploadedDataset[]>([]);
   const [coverage, setCoverage] = useState<CoveragePayload | null>(null);
+  const [acceptance, setAcceptance] = useState<AcceptancePayload | null>(null);
   const [error, setError] = useState<string>("");
 
   async function refresh() {
     try {
-      const [catalogNext, gpusNext, jobsNext, resultsNext, datasetsNext, coverageNext] = await Promise.all([
+      const [catalogNext, gpusNext, jobsNext, resultsNext, datasetsNext, coverageNext, acceptanceNext] = await Promise.all([
         api<Catalog>("/api/catalog"),
         api<GpuPayload>("/api/system/gpus"),
         api<Job[]>("/api/jobs"),
         api<ResultItem[]>("/api/results"),
         api<UploadedDataset[]>("/api/datasets"),
-        api<CoveragePayload>("/api/coverage")
+        api<CoveragePayload>("/api/coverage"),
+        api<AcceptancePayload>("/api/acceptance/latest")
       ]);
       setCatalog(catalogNext);
       setGpus(gpusNext);
@@ -170,6 +180,7 @@ function useData() {
       setResults(resultsNext.slice(0, 80));
       setDatasets(datasetsNext);
       setCoverage(coverageNext);
+      setAcceptance(acceptanceNext);
       setError("");
     } catch (err) {
       setError(String(err));
@@ -182,7 +193,7 @@ function useData() {
     return () => window.clearInterval(timer);
   }, []);
 
-  return { catalog, gpus, jobs, results, datasets, coverage, error, refresh };
+  return { catalog, gpus, jobs, results, datasets, coverage, acceptance, error, refresh };
 }
 
 function StatusPill({ status }: { status: string }) {
@@ -190,7 +201,7 @@ function StatusPill({ status }: { status: string }) {
 }
 
 function App() {
-  const { catalog, gpus, jobs, results, datasets, coverage, error, refresh } = useData();
+  const { catalog, gpus, jobs, results, datasets, coverage, acceptance, error, refresh } = useData();
   const [taskType, setTaskType] = useState("mock.echo");
   const [params, setParams] = useState(JSON.stringify(defaultParams["mock.echo"], null, 2));
   const [selectedJob, setSelectedJob] = useState<Job | null>(null);
@@ -255,6 +266,16 @@ function App() {
     }
   }
 
+  async function runAcceptanceSmoke() {
+    setBusy(true);
+    try {
+      await api("/api/acceptance/smoke", { method: "POST" });
+      await refresh();
+    } finally {
+      setBusy(false);
+    }
+  }
+
   async function createDataset() {
     setBusy(true);
     try {
@@ -497,7 +518,9 @@ function App() {
                 <p className="eyebrow">Coverage</p>
                 <h2>Seg 功能覆盖</h2>
               </div>
-              <ClipboardCheck size={22} />
+              <button className="iconButton" disabled={busy} onClick={runAcceptanceSmoke} title="运行轻量验收">
+                <ClipboardCheck size={18} />
+              </button>
             </div>
             <div className="coverageGrid">
               <div>
@@ -512,10 +535,17 @@ function App() {
                 <span>任务构建</span>
                 <strong>{coverage?.task_build_passed ? "OK" : "Check"}</strong>
               </div>
+              <div>
+                <span>轻量验收</span>
+                <strong>{acceptance?.available === false ? "New" : acceptance?.passed ? "OK" : "Check"}</strong>
+              </div>
             </div>
             <div className="coverageStatus">
               {(coverage?.unmapped_user_scripts.length ?? 0) === 0 ? (
-                <span>当前用户侧脚本已全部映射到网页任务。</span>
+                <>
+                  <span>当前用户侧脚本已全部映射到网页任务。</span>
+                  <span>最近验收：{acceptance?.created_at ?? "尚未运行"} {acceptance?.run_id ? `#${acceptance.run_id}` : ""}</span>
+                </>
               ) : (
                 coverage?.unmapped_user_scripts.slice(0, 8).map((item) => <code key={item}>{item}</code>)
               )}
diff --git a/frontend/src/styles.css b/frontend/src/styles.css
index 6a21fb6..c41016e 100644
--- a/frontend/src/styles.css
+++ b/frontend/src/styles.css
@@ -399,7 +399,7 @@ textarea {
 
 .coverageGrid {
   display: grid;
-  grid-template-columns: repeat(3, minmax(0, 1fr));
+  grid-template-columns: repeat(4, minmax(0, 1fr));
   gap: 10px;
   margin-bottom: 14px;
 }