diff --git a/apps/api/src/services/ai_providers/ollama.py b/apps/api/src/services/ai_providers/ollama.py
index eb5dce07..49a7bdb6 100644
--- a/apps/api/src/services/ai_providers/ollama.py
+++ b/apps/api/src/services/ai_providers/ollama.py
@@ -133,3 +133,127 @@ class OllamaProvider:
         if self._http_client:
             await self._http_client.aclose()
             self._http_client = None
+
+
+# 2026-04-26 Wave5 B1-fix by Claude Engineer-A4 — OLLAMA_188 provider 註冊
+class Ollama188Provider(OllamaProvider):
+    """
+    Ollama 188 CPU-only 備援 Provider
+
+    繼承 OllamaProvider，但使用 OLLAMA_FALLBACK_URL（192.168.0.188:11434）
+    作為推理端點，模型預設 OLLAMA_HEALTH_CHECK_MODEL（qwen2.5:7b-instruct）。
+
+    B1 修復：原本 _init_registry 未登錄此 provider，導致
+    executor.execute() 遇到 "ollama_188" → not_registered → 跳過，
+    188 從未被打到。此類別補全登錄鏈路。
+
+    2026-04-26 Wave5 B1-fix by Claude Engineer-A4
+    """
+
+    @property
+    def name(self) -> str:
+        return "ollama_188"
+
+    @property
+    def is_enabled(self) -> bool:
+        import os
+        # 優先查 ENABLE_OLLAMA_188；若未設定（預設 true）則看 OLLAMA_FALLBACK_URL 是否有值
+        env_override = os.getenv("ENABLE_OLLAMA_188", "true").lower() == "true"
+        if not env_override:
+            return False
+        # OLLAMA_FALLBACK_URL 空字串 → 未設定 188 節點 → 停用
+        return bool(getattr(settings, "OLLAMA_FALLBACK_URL", ""))
+
+    async def analyze(
+        self,
+        prompt: str,
+        context: dict | None = None,
+    ) -> AIResult:
+        start = time.perf_counter()
+        fallback_url = getattr(settings, "OLLAMA_FALLBACK_URL", "")
+        if not fallback_url:
+            return AIResult(
+                raw_response="",
+                success=False,
+                provider=self.name,
+                error="OLLAMA_FALLBACK_URL not configured",
+            )
+
+        try:
+            client = await self._get_client()
+
+            registry = get_model_registry()
+            # 嘗試取 ollama_188 專屬設定，fallback 到 ollama 預設
+            try:
+                model_name = registry.get_model("ollama_188", "rca")
+            except Exception:
+                model_name = getattr(settings, "OLLAMA_HEALTH_CHECK_MODEL", "qwen2.5:7b-instruct")
+
+            try:
+                options = registry.get_provider_options("ollama_188")
+            except Exception:
+                options = registry.get_provider_options("ollama")
+
+            # CPU-only 備援：固定使用較長 timeout（CPU 推理慢）
+            task_type = (context or {}).get("task_type", "")
+            if task_type in ("diagnose", "force_local"):
+                read_timeout = float(getattr(settings, "OLLAMA_DIAGNOSE_TIMEOUT_SECONDS", 200))
+            else:
+                read_timeout = float(settings.OPENCLAW_TIMEOUT)
+
+            response = await client.post(
+                f"{fallback_url}/api/generate",
+                json={
+                    "model": model_name,
+                    "prompt": prompt,
+                    "stream": False,
+                    "format": "json",
+                    "options": {
+                        "num_predict": options.get("num_predict", 1024),
+                        "temperature": options.get("temperature", 0.1),
+                        "top_p": options.get("top_p", 0.9),
+                    },
+                },
+                timeout=httpx.Timeout(read_timeout, connect=10.0),
+            )
+            response.raise_for_status()
+            data = response.json()
+            result = data.get("response", "")
+            tokens = data.get("eval_count", 0) + data.get("prompt_eval_count", 0)
+            latency = (time.perf_counter() - start) * 1000
+
+            logger.info(
+                "ollama_188_provider_success",
+                response_length=len(result),
+                tokens=tokens,
+                latency_ms=round(latency, 1),
+                endpoint=fallback_url,
+            )
+            return AIResult(
+                raw_response=result,
+                success=True,
+                provider=self.name,
+                tokens=tokens,
+                latency_ms=latency,
+            )
+
+        except httpx.TimeoutException as e:
+            latency = (time.perf_counter() - start) * 1000
+            logger.warning("ollama_188_provider_timeout", error=str(e), latency_ms=round(latency, 1))
+            return AIResult(raw_response="", success=False, provider=self.name, latency_ms=latency, error=f"Timeout: {e}")
+
+        except Exception as e:
+            latency = (time.perf_counter() - start) * 1000
+            logger.warning("ollama_188_provider_failed", error=str(e), latency_ms=round(latency, 1))
+            return AIResult(raw_response="", success=False, provider=self.name, latency_ms=latency, error=str(e))
+
+    async def health_check(self) -> bool:
+        fallback_url = getattr(settings, "OLLAMA_FALLBACK_URL", "")
+        if not fallback_url:
+            return False
+        try:
+            client = await self._get_client()
+            resp = await client.get(f"{fallback_url}/api/tags", timeout=5.0)
+            return resp.status_code == 200
+        except Exception:
+            return False
diff --git a/apps/api/src/services/ai_router.py b/apps/api/src/services/ai_router.py
index 634ae7dc..f939032b 100644
--- a/apps/api/src/services/ai_router.py
+++ b/apps/api/src/services/ai_router.py
@@ -1191,7 +1191,7 @@ _executor: AIRouterExecutor | None = None
 
 def _init_registry() -> AIProviderRegistry:
     """初始化 Provider Registry (首次呼叫時自動註冊所有 Provider)"""
-    from src.services.ai_providers.ollama import OllamaProvider
+    from src.services.ai_providers.ollama import OllamaProvider, Ollama188Provider  # 2026-04-26 Wave5 B1-fix by Claude Engineer-A4
     from src.services.ai_providers.gemini import GeminiProvider
     from src.services.ai_providers.claude import ClaudeProvider
     from src.services.ai_providers.openclaw_nemo import OpenClawNemoProvider
@@ -1206,6 +1206,11 @@ def _init_registry() -> AIProviderRegistry:
     from src.services.ai_providers.nemotron import NemotronProvider
     registry.register(NemotronProvider())
 
+    # 2026-04-26 Wave5 B1-fix by Claude Engineer-A4 — 補登 OLLAMA_188 備援 provider
+    # 修復：原本 failover_manager 決策返回 "ollama_188"，但 executor 查不到 → not_registered
+    # → 188 從未被打到。必須明確 register 才能讓 executor.execute() 路由到 188。
+    registry.register(Ollama188Provider())
+
     return registry
 
 
diff --git a/apps/api/src/services/auto_repair_service.py b/apps/api/src/services/auto_repair_service.py
index 4c29510c..312d85fb 100644
--- a/apps/api/src/services/auto_repair_service.py
+++ b/apps/api/src/services/auto_repair_service.py
@@ -435,6 +435,51 @@ class AutoRepairService:
             except Exception as _rg_e:
                 logger.warning("runbook_generator_task_failed", error=str(_rg_e))
 
+            # 2026-04-26 Wave4 P1.3+P1.4 by Claude Engineer-B3 — 飛輪閉環最後一哩
+            # 成功執行後，fire-and-forget 啟動後執行驗證 + EWMA 學習回饋
+            # verifier 有 10s warmup + 30s timeout，不能阻塞在主路徑
+            try:
+                import asyncio as _asyncio
+                from src.services.post_execution_verifier import get_post_execution_verifier
+                from src.services.learning_service import get_learning_service
+
+                _action_taken = f"auto_repair:{playbook.playbook_id}"
+                _verifier = get_post_execution_verifier()
+                _learning = get_learning_service()
+
+                async def _verify_and_learn() -> None:
+                    try:
+                        verification_result = await _verifier.verify(
+                            incident=incident,
+                            snapshot=None,
+                            action_taken=_action_taken,
+                        )
+                        await _learning.record_verification_result(
+                            incident_id=incident.incident_id,
+                            action_taken=_action_taken,
+                            verification_result=verification_result,
+                            matched_playbook_id=playbook.playbook_id,
+                        )
+                        logger.info(
+                            "auto_repair_verify_and_learn_done",
+                            incident_id=incident.incident_id,
+                            playbook_id=playbook.playbook_id,
+                            verification_result=verification_result,
+                        )
+                    except Exception as _inner_e:
+                        logger.warning(
+                            "auto_repair_verify_and_learn_failed",
+                            incident_id=incident.incident_id,
+                            error=str(_inner_e),
+                        )
+
+                _vl_task = _asyncio.create_task(_verify_and_learn())
+                if hasattr(self, "_pending_tasks"):
+                    self._pending_tasks.add(_vl_task)
+                    _vl_task.add_done_callback(self._pending_tasks.discard)
+            except Exception as _vl_e:
+                logger.warning("auto_repair_verifier_setup_failed", error=str(_vl_e))
+
             return repair_result
 
         except Exception as e:
diff --git a/apps/api/src/services/ollama_failover_manager.py b/apps/api/src/services/ollama_failover_manager.py
index b342a327..dab53202 100644
--- a/apps/api/src/services/ollama_failover_manager.py
+++ b/apps/api/src/services/ollama_failover_manager.py
@@ -413,13 +413,21 @@ class OllamaFailoverManager:
                 return True  # fail-open
             quota = getattr(self._settings, "GEMINI_DAILY_QUOTA", 1000)
             key = f"ollama:gemini_daily_count:{datetime.date.today().isoformat()}"
-            count_raw = await redis.get(key)
-            count = int(count_raw or 0)
-            if count >= quota:
+
+            # 2026-04-26 Wave5 B3-fix by Claude Engineer-A4 — atomic pipeline 修復 TOCTOU
+            # 原實作：GET → 判斷 → INCR → EXPIRE（分四步，INCR 後 crash 會丟 TTL，
+            # 且並行請求在 GET/INCR 之間競爭導致配額超發）
+            # 修法：pipeline 原子執行 SET NX（首次設 TTL） + INCR，用 INCR 後的新值判斷
+            pipe = redis.pipeline()
+            pipe.set(key, 0, ex=86400, nx=True)  # 僅首次寫入設 TTL；已存在則跳過
+            pipe.incr(key)                        # 原子遞增，回傳遞增後的值
+            results = await pipe.execute()
+            new_count = int(results[1])           # results[1] = INCR 後新值
+
+            if new_count > quota:
+                # 已超配額（INCR 後 > quota），回退不是必要的（最多超發 1 次）
+                # 但要回傳 False 讓 router 切到 188
                 return False
-            # atomic incr + 設定 TTL（確保跨日自動重置）
-            await redis.incr(key)
-            await redis.expire(key, 86400)
             return True
         except Exception as e:
             logger.warning("gemini_quota_check_failed", error=str(e))
diff --git a/apps/api/tests/test_learning_chain_e2e.py b/apps/api/tests/test_learning_chain_e2e.py
new file mode 100644
index 00000000..977bde76
--- /dev/null
+++ b/apps/api/tests/test_learning_chain_e2e.py
@@ -0,0 +1,377 @@
+"""
+飛輪閉環 E2E 測試 — auto_repair → PostExecutionVerifier → LearningService → EWMA
+================================================================================
+2026-04-26 Wave4 P1.3+P1.4 by Claude Engineer-B3 — 飛輪閉環最後一哩
+
+測試範圍:
+  - execute_auto_repair 成功 → verifier 被呼叫 → record_verification_result 被呼叫
+  - execute_auto_repair 失敗 → verifier 不被呼叫（主 except 路徑）
+  - matched_playbook_id=None 的 record_verification_result → log warning 不 crash
+  - verifier 拋例外 → 修復仍回傳成功，trust 不更新
+
+🔴 遵循 feedback_no_mock_testing.md:
+  - 禁止 MagicMock/AsyncMock/unittest.mock.patch
+  - 使用純 Python Stub 類別 + pytest monkeypatch（替換 module-level getter）
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import pytest
+
+from src.models.incident import Incident, IncidentStatus, Severity, Signal
+from src.models.playbook import (
+    ActionType,
+    Playbook,
+    PlaybookStatus,
+    RepairStep,
+    RiskLevel,
+    SymptomPattern,
+)
+from src.services.auto_repair_service import AutoRepairService
+from src.utils.timezone import now_taipei
+
+
+# =============================================================================
+# Stubs
+# =============================================================================
+
+
+class StubVerifier:
+    """PostExecutionVerifier 的輕量 Stub — 記錄呼叫，不真正等 K8s"""
+
+    def __init__(self, result: str = "success", raise_exc: Exception | None = None):
+        self.result = result
+        self.raise_exc = raise_exc
+        self.calls: list[dict] = []
+
+    async def verify(
+        self,
+        incident,
+        snapshot,
+        action_taken: str,
+        warmup_sec: float = 0.0,
+    ) -> str:
+        self.calls.append(
+            {"incident_id": incident.incident_id, "snapshot": snapshot, "action_taken": action_taken}
+        )
+        if self.raise_exc is not None:
+            raise self.raise_exc
+        return self.result
+
+
+class StubLearningService:
+    """LearningService 的輕量 Stub — 記錄 record_verification_result 呼叫"""
+
+    def __init__(self) -> None:
+        self.verification_calls: list[dict] = []
+
+    async def record_verification_result(
+        self,
+        incident_id: str,
+        action_taken: str,
+        verification_result: str,
+        matched_playbook_id: str | None = None,
+    ) -> None:
+        self.verification_calls.append(
+            {
+                "incident_id": incident_id,
+                "action_taken": action_taken,
+                "verification_result": verification_result,
+                "matched_playbook_id": matched_playbook_id,
+            }
+        )
+
+
+class StubPlaybookService:
+    """PlaybookService 的輕量 Stub — 支援 record_execution + get_recommendations"""
+
+    def __init__(self) -> None:
+        self._playbooks: dict[str, Playbook] = {}
+        self._recommendations: list = []
+
+    def add_playbook(self, playbook: Playbook) -> None:
+        self._playbooks[playbook.playbook_id] = playbook
+
+    def set_recommendations(self, recommendations: list) -> None:
+        self._recommendations = recommendations
+
+    async def get_recommendations(self, symptoms, top_k: int = 3) -> list:
+        return self._recommendations
+
+    async def get_by_id(self, playbook_id: str) -> Playbook | None:
+        return self._playbooks.get(playbook_id)
+
+    async def record_execution(self, playbook_id: str, success: bool) -> bool:
+        playbook = self._playbooks.get(playbook_id)
+        if playbook is not None:
+            if success:
+                playbook.success_count += 1
+            else:
+                playbook.failure_count += 1
+        return playbook is not None
+
+
+class StubRecommendation:
+    def __init__(self, playbook: Playbook, similarity_score: float = 0.9) -> None:
+        self.playbook = playbook
+        self.similarity_score = similarity_score
+
+
+# =============================================================================
+# Factories
+# =============================================================================
+
+
+def _make_incident(
+    incident_id: str = "INC-E2E-001",
+    severity: Severity = Severity.P2,
+) -> Incident:
+    now = now_taipei()
+    return Incident(
+        incident_id=incident_id,
+        status=IncidentStatus.INVESTIGATING,
+        severity=severity,
+        affected_services=["e2e-service"],
+        signals=[
+            Signal(
+                alert_name="TestAlert",
+                severity=severity,
+                source="prometheus",
+                fired_at=now,
+                labels={"namespace": "awoooi-prod", "alertname": "TestAlert"},
+            )
+        ],
+    )
+
+
+def _make_playbook(
+    playbook_id: str = "PB-E2E-001",
+    trust_score: float = 0.5,
+) -> Playbook:
+    pb = Playbook(
+        playbook_id=playbook_id,
+        name="E2E 測試 Playbook",
+        description="飛輪閉環 E2E 測試用",
+        status=PlaybookStatus.APPROVED,
+        symptom_pattern=SymptomPattern(
+            alert_names=["TestAlert"],
+            affected_services=["e2e-service"],
+            severity_range=["P2"],
+        ),
+        repair_steps=[
+            RepairStep(
+                step_number=1,
+                action_type=ActionType.MANUAL,
+                command="echo test",
+                risk_level=RiskLevel.LOW,
+            )
+        ],
+        trust_score=trust_score,
+        success_count=5,
+        failure_count=1,
+    )
+    return pb
+
+
+async def _no_cooldown(*args, **kwargs) -> tuple[bool, str]:
+    return True, "允許修復 (test bypass)"
+
+
+# =============================================================================
+# Tests
+# =============================================================================
+
+
+@pytest.mark.asyncio
+async def test_auto_repair_success_triggers_verify_and_learn(monkeypatch):
+    """
+    執行成功 → verifier.verify() 被呼叫 → record_verification_result 被呼叫
+    驗證飛輪鏈路的前兩段接通。
+    """
+    stub_verifier = StubVerifier(result="success")
+    stub_learning = StubLearningService()
+
+    # 替換 module-level getters（pure Python, no MagicMock）
+    import src.services.auto_repair_service as _ars_mod
+    monkeypatch.setattr(_ars_mod, "_verifier_getter", None, raising=False)
+
+    import src.services.post_execution_verifier as _pev_mod
+    monkeypatch.setattr(_pev_mod, "_verifier", stub_verifier)
+
+    import src.services.learning_service as _ls_mod
+    monkeypatch.setattr(_ls_mod, "_learning_service", stub_learning)
+
+    playbook = _make_playbook()
+    pb_service = StubPlaybookService()
+    pb_service.add_playbook(playbook)
+    pb_service.set_recommendations([StubRecommendation(playbook)])
+
+    service = AutoRepairService(
+        playbook_service=pb_service,
+        cooldown_checker=_no_cooldown,
+    )
+
+    incident = _make_incident()
+    result = await service.execute_auto_repair(incident, playbook)
+
+    assert result.success is True
+
+    # fire-and-forget task — 讓 event loop 執行完
+    # verifier 有 warmup_sec，但 Stub 忽略 warmup（不 sleep）
+    await asyncio.sleep(0.05)
+
+    assert len(stub_verifier.calls) == 1, "verifier.verify() 應被呼叫一次"
+    assert stub_verifier.calls[0]["incident_id"] == incident.incident_id
+    assert stub_verifier.calls[0]["snapshot"] is None
+
+    assert len(stub_learning.verification_calls) == 1, "record_verification_result 應被呼叫一次"
+    call = stub_learning.verification_calls[0]
+    assert call["incident_id"] == incident.incident_id
+    assert call["verification_result"] == "success"
+    assert call["matched_playbook_id"] == playbook.playbook_id
+
+
+@pytest.mark.asyncio
+async def test_auto_repair_failure_does_not_call_verifier(monkeypatch):
+    """
+    執行失敗（步驟拋例外）→ verifier 不被呼叫（失敗路徑不進入 verify-and-learn 區塊）
+    """
+    stub_verifier = StubVerifier(result="success")
+
+    import src.services.post_execution_verifier as _pev_mod
+    monkeypatch.setattr(_pev_mod, "_verifier", stub_verifier)
+
+    import src.services.learning_service as _ls_mod
+    stub_learning = StubLearningService()
+    monkeypatch.setattr(_ls_mod, "_learning_service", stub_learning)
+
+    # 建立一個會讓 _execute_step raise 的 playbook（KUBECTL 步驟，executor 不可用時只 skip，不 raise）
+    # 直接讓 playbook_service.record_execution 正常工作，驗證失敗路徑不呼叫 verifier
+
+    class FailingPlaybookService(StubPlaybookService):
+        async def record_execution(self, playbook_id: str, success: bool) -> bool:
+            # 正常記錄，不 raise
+            return True
+
+    playbook = _make_playbook()
+    pb_service = FailingPlaybookService()
+    pb_service.add_playbook(playbook)
+
+    # 讓 _execute_step 拋例外以觸發失敗路徑
+    original_execute_step = AutoRepairService._execute_step
+
+    async def _always_fail(self_inner, incident_arg, step_arg) -> str:
+        raise RuntimeError("強制測試失敗")
+
+    service = AutoRepairService(
+        playbook_service=pb_service,
+        cooldown_checker=_no_cooldown,
+    )
+    # Monkeypatch instance method
+    monkeypatch.setattr(AutoRepairService, "_execute_step", _always_fail)
+
+    incident = _make_incident()
+    result = await service.execute_auto_repair(incident, playbook)
+
+    assert result.success is False
+
+    await asyncio.sleep(0.05)
+
+    # 失敗路徑不進入 verify-and-learn 塊
+    assert len(stub_verifier.calls) == 0, "執行失敗時不應呼叫 verifier"
+    assert len(stub_learning.verification_calls) == 0, "執行失敗時不應呼叫 record_verification_result"
+
+
+@pytest.mark.asyncio
+async def test_record_verification_result_no_playbook_id_does_not_crash():
+    """
+    matched_playbook_id=None → record_verification_result 正常執行，不 crash。
+    驗證 learning_service 對 None playbook_id 的防禦性。
+    """
+    from src.services.learning_service import LearningService
+    from src.repositories.interfaces import ILearningRepository, ITrustRepository
+
+    class NullLearningRepo:
+        async def record_repair(self, **kwargs) -> bool:
+            return True
+
+        async def get_repair_stats(self, *a, **kw):
+            return {}
+
+        async def get_all_repair_stats(self, *a, **kw):
+            return {}
+
+        async def record_disposition(self, *a, **kw):
+            return True
+
+        async def get_dispositions(self, *a, **kw):
+            return {}
+
+    class NullTrustRepo:
+        async def save_trust_record(self, *a, **kw):
+            pass
+
+        async def load_trust_record(self, *a, **kw):
+            return None
+
+        async def get_all_trust_records(self, *a, **kw):
+            return []
+
+    # 直接呼叫 record_verification_result(matched_playbook_id=None)
+    # 不應 raise，只應 log warning 並略過 _update_playbook_stats
+    svc = LearningService(
+        repository=NullLearningRepo(),
+        trust_repository=NullTrustRepo(),
+    )
+
+    # 不應拋例外
+    await svc.record_verification_result(
+        incident_id="INC-NULL-PB-001",
+        action_taken="auto_repair:none",
+        verification_result="success",
+        matched_playbook_id=None,
+    )
+    # 只要不 crash 即通過
+
+
+@pytest.mark.asyncio
+async def test_verifier_exception_does_not_block_repair(monkeypatch):
+    """
+    verifier 拋例外 → 修復結果仍回傳 success=True，learning 不被呼叫。
+    驗證 _verify_and_learn 的 exception 隔離。
+    """
+    stub_verifier = StubVerifier(
+        result="success",
+        raise_exc=RuntimeError("verifier 模擬故障"),
+    )
+    stub_learning = StubLearningService()
+
+    import src.services.post_execution_verifier as _pev_mod
+    monkeypatch.setattr(_pev_mod, "_verifier", stub_verifier)
+
+    import src.services.learning_service as _ls_mod
+    monkeypatch.setattr(_ls_mod, "_learning_service", stub_learning)
+
+    playbook = _make_playbook()
+    pb_service = StubPlaybookService()
+    pb_service.add_playbook(playbook)
+
+    service = AutoRepairService(
+        playbook_service=pb_service,
+        cooldown_checker=_no_cooldown,
+    )
+
+    incident = _make_incident()
+    result = await service.execute_auto_repair(incident, playbook)
+
+    # 主路徑成功回傳
+    assert result.success is True
+
+    await asyncio.sleep(0.05)
+
+    # verifier 被呼叫（但拋了例外）
+    assert len(stub_verifier.calls) == 1
+    # learning 不應被呼叫（因為 verifier raise 中斷了 _verify_and_learn）
+    assert len(stub_learning.verification_calls) == 0, "verifier 拋例外後 learning 不應被呼叫"