diff --git a/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/README.md b/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/README.md
new file mode 100644
index 00000000..0650ea44
--- /dev/null
+++ b/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/README.md
@@ -0,0 +1,25 @@
+# Optional Cluster Copilot component
+
+Compose this component only with `../cluster-ai`. It enables the caller-driven
+failure-diagnosis capability inside the existing Cluster AI process; it does
+not add an HTTP route, queue, watcher, timer, PostgreSQL pool, provider, or
+Model Gateway.
+
+Before production use:
+
+1. Replace the example provider, model and egress policy revision in
+   `copilot-configmap.yaml`. Keep `config.json` canonical, one-line JSON with
+   one trailing newline.
+2. Provision these three Secrets out of band, each containing a canonical
+   `keyring.json`: `ql3-cluster-ai-copilot-invocation-keyring`,
+   `ql3-cluster-ai-copilot-result-keyring`, and
+   `ql3-cluster-ai-copilot-output-keyring`.
+3. Keep old decryptable keys during rotation. Invocation, Tool result and
+   Copilot output keys are independent authorities and must never reuse
+   material.
+4. Keep Worker ingress and its bounded S3 log-range reader enabled. Startup
+   fails closed if the log capability, canonical config, any keyring, or the
+   shared successful-completion sink is unavailable.
+
+All projections are read-only mode `0440`. The component adds no Kubernetes
+API permission and does not change the default AI-free deployment.
diff --git a/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/copilot-configmap.yaml b/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/copilot-configmap.yaml
new file mode 100644
index 00000000..a0e3d014
--- /dev/null
+++ b/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/copilot-configmap.yaml
@@ -0,0 +1,7 @@
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: ql3-cluster-ai-copilot
+data:
+  config.json: |
+    {"schema":"qinglong/cluster-copilot-failure-diagnosis-config@v1","provider":"provider-primary","model":"model-diagnosis","modelBoundary":"external","responseLanguage":"zh-CN","maxOutputTokens":512,"executionTimeoutMs":60000,"egressPolicy":{"schema":"qinglong/copilot-model-egress-policy@v1","revision":"replace-before-production","potentiallySensitiveDataBoundaries":["external"],"maxInputBytes":65536,"maxOutputTokens":1024}}
diff --git a/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/deployment-patch.yaml b/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/deployment-patch.yaml
new file mode 100644
index 00000000..db4e27bf
--- /dev/null
+++ b/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/deployment-patch.yaml
@@ -0,0 +1,62 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: ql3-cluster-control
+spec:
+  template:
+    spec:
+      containers:
+        - name: cluster-control
+          env:
+            - name: QL3_CLUSTER_AI_COPILOT_ENABLED
+              value: "true"
+            - name: QL3_CLUSTER_AI_COPILOT_CONFIG_FILE
+              value: /var/run/qinglong3/ai/copilot-config/config.json
+            - name: QL3_CLUSTER_AI_COPILOT_INVOCATION_KEYRING_ROOT
+              value: /var/run/secrets/qinglong3/ai/copilot-invocation-keyring
+            - name: QL3_CLUSTER_AI_COPILOT_RESULT_KEYRING_ROOT
+              value: /var/run/secrets/qinglong3/ai/copilot-result-keyring
+            - name: QL3_CLUSTER_AI_COPILOT_OUTPUT_KEYRING_ROOT
+              value: /var/run/secrets/qinglong3/ai/copilot-output-keyring
+          volumeMounts:
+            - name: cluster-ai-copilot-config
+              mountPath: /var/run/qinglong3/ai/copilot-config
+              readOnly: true
+            - name: cluster-ai-copilot-invocation-keyring
+              mountPath: /var/run/secrets/qinglong3/ai/copilot-invocation-keyring
+              readOnly: true
+            - name: cluster-ai-copilot-result-keyring
+              mountPath: /var/run/secrets/qinglong3/ai/copilot-result-keyring
+              readOnly: true
+            - name: cluster-ai-copilot-output-keyring
+              mountPath: /var/run/secrets/qinglong3/ai/copilot-output-keyring
+              readOnly: true
+      volumes:
+        - name: cluster-ai-copilot-config
+          configMap:
+            name: ql3-cluster-ai-copilot
+            defaultMode: 288
+            items:
+              - key: config.json
+                path: config.json
+        - name: cluster-ai-copilot-invocation-keyring
+          secret:
+            secretName: ql3-cluster-ai-copilot-invocation-keyring
+            defaultMode: 288
+            items:
+              - key: keyring.json
+                path: keyring.json
+        - name: cluster-ai-copilot-result-keyring
+          secret:
+            secretName: ql3-cluster-ai-copilot-result-keyring
+            defaultMode: 288
+            items:
+              - key: keyring.json
+                path: keyring.json
+        - name: cluster-ai-copilot-output-keyring
+          secret:
+            secretName: ql3-cluster-ai-copilot-output-keyring
+            defaultMode: 288
+            items:
+              - key: keyring.json
+                path: keyring.json
diff --git a/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/kustomization.yaml b/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/kustomization.yaml
new file mode 100644
index 00000000..1792e0e6
--- /dev/null
+++ b/deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot/kustomization.yaml
@@ -0,0 +1,8 @@
+apiVersion: kustomize.config.k8s.io/v1alpha1
+kind: Component
+
+resources:
+  - copilot-configmap.yaml
+
+patches:
+  - path: deployment-patch.yaml
diff --git a/deploy/kubernetes/ql3-cluster/overlays/cluster-ai-copilot-example/kustomization.yaml b/deploy/kubernetes/ql3-cluster/overlays/cluster-ai-copilot-example/kustomization.yaml
new file mode 100644
index 00000000..8fd41a0e
--- /dev/null
+++ b/deploy/kubernetes/ql3-cluster/overlays/cluster-ai-copilot-example/kustomization.yaml
@@ -0,0 +1,16 @@
+# Example only. Copy into a private overlay, replace all example model policy
+# values and provision the three keyring Secrets out of band.
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+resources:
+  - ../../base
+
+components:
+  - ../../components/cluster-ai
+  - ../../components/cluster-ai-copilot
+
+images:
+  - name: qinglong3-cluster-control-ai
+    newName: registry.example.com/qinglong/qinglong3-cluster-control-ai
+    digest: sha256:0000000000000000000000000000000000000000000000000000000000000000
diff --git a/docs/QINGLONG_3_0_ARCHITECTURE_RFC.md b/docs/QINGLONG_3_0_ARCHITECTURE_RFC.md
index 2b6c7e06..29c6faed 100644
--- a/docs/QINGLONG_3_0_ARCHITECTURE_RFC.md
+++ b/docs/QINGLONG_3_0_ARCHITECTURE_RFC.md
@@ -11,6 +11,7 @@
 
 最新增量证据（2026-08-15）：
 
+- D-319/ADR-0411（已接受）：Cluster Copilot failure diagnosis 已在既有 `ql3-cluster-control-ai` 进程内完成默认关闭的 production composition。Prompt 与 Copilot 共享同一个 PostgreSQL AI Pool、Model Gateway、Provider client、恢复扫描、quota/pricing ledger 与 `maxConcurrent` 预算；有界 successful-completion router 只向声明 exact invocation 的 durable sink 分发，不复制 Gateway、连接或隐藏队列。application service 只接受 source Run/request identity，从数据库当前 Run、latest Attempt、Project Tool snapshot、Policy 和 canonical read-only egress config 派生计划，先 admission，再以 durable plan、historical key 与确定性 nonce 修复 admission→Artifact crash window，随后复用 Trusted Tool、Worker Artifact range reader、Model Gateway 及独立的 invocation/result/model-output 三域 keyring。能力保持 caller-driven，不增加 timer、watcher、队列、HTTP/CLI/UI/MCP route 或 Kubernetes API 权限；Kubernetes 独立可选 component 仅投影 config 与三个 0440 keyring。最终 AI 238 pass/3 条件 skip、Cluster Control 240 pass/2 条件 skip、18-package clean build/test 与 backend 1,207 pass/2 条件 skip/0 fail，四项架构审计、14 档 Local artifact 全部通过；workspace 仍为 18 package、无单文件/浅平 package，AI 187 个源码中 186 个、Cluster Control 59 个中 57 个位于嵌套领域目录。默认 Edge/Standalone 保持 2,589,890/2,589,968 bytes，Edge/Standalone AI 为 3,064,454/3,064,544 bytes，证明 Cluster-only composition 未进入小设备闭包。PostgreSQL 18.6 arm64 HA 130/130、timeline `1→2`，报告 SHA-256 为 `981299b454dce5541e9596450b85816dc40559cba8dc42adf3d5fea571c3d3a6`；本 Gate 不改 migration/schema/role/SQL/HA 拓扑。下一 Gate 是 Tool failure、日志 missing/retired/pending、deadline/cancel 与 Model outcome-unknown 的 durable terminalization/recovery，完成前不开放产品入口。
 - D-318/ADR-0410（已接受）：Cluster Copilot diagnosis Model output 获得独立的只读 projected key authority。canonical `qinglong/copilot-failure-diagnosis-output-projected-keyring@v1` manifest 只允许一个 active key 与最多 16 个 historical 32-byte key；每次 `active()`/`resolve()` 都重新执行 Cluster 私有投影文件的 direct-root、根内 atomic symlink、single-link、mode、dev/inode/size/mtime 与双 realpath fence，不使用 cache、watcher、timer 或 Kubernetes API。该 authority 以结构兼容的本地窄端口位于既有 `cluster-control/copilot/failure-diagnosis/`，只通过 `failure-diagnosis-output-keyring` subpath 发布，避免 Cluster Control 默认源码反向依赖 AI；它不复用 Prompt output、Tool invocation/result 或 Provider credential key domain，也不提前声称 Copilot 产品入口已可达。定向回归 13/13、Cluster Control 239 pass/2 条件 skip、backend 1,207 pass/2 条件 skip、18-package clean build/test、四项架构审计与 14 档 Local artifact 全部通过；workspace 仍无单文件/浅平 package，Cluster Control 58 个源码中 56 个位于嵌套领域目录。默认 Edge/Standalone 保持 2,589,890/2,589,968 bytes，Edge/Standalone AI 保持 3,061,009/3,061,099 bytes，证明 Cluster-only subpath 被裁掉。本 Gate 不改 migration/schema/role/SQL/连接/HA 拓扑，因此数据库基线继续引用 ADR-0409 的 PostgreSQL 18.6 arm64 HA 130/130、timeline `1→2`；下一 Gate 是默认关闭的完整 Cluster Copilot composition，随后补齐 Tool failure、日志 missing/retired、Model admission 前 deadline/cancel 与 outcome-unknown 的 durable terminalization/recovery。
 - D-316/ADR-0408（已接受）：Cluster Copilot 现在能够从 ADR-0407 的 durable admission 恢复 exact `qinglong.run.log.excerpt@1.0.0` authority，复用通用 Trusted Tool start barrier、加密 success/failure completion、result catalog/rekey 和内建日志 adapter；确定性 start/completion identity 让 response-loss replay 直接打开既有证据，不重复读取日志或执行 adapter。Cluster invocation Artifact 使用独立 projected keyring，提供 active+historical material，但每次读取均重新执行 canonical path/symlink/mode/inode/realpath fence，且不取得 PostgreSQL Tool result generation authority。只有 exact `succeeded` completion 才能通过 `pg-9019` 的 SERIALIZABLE 事务把 Model Step 从 `pending` 原子推进到 `ready`，同时写 RunEvent、StepRunMutation 和 append-only unlock receipt；`failed|timed_out` 不解锁。本 Gate 不执行模型、不终态化 diagnosis Run，下一 Gate 是 ADR-0405 builder + Model Gateway + Copilot encrypted model completion/terminalization。实现仍为 18 个 package，无单文件/浅平 package；AI 175 个源码中 174 个、Cluster Control 56 个中 54 个位于嵌套目录，不新增依赖、进程、连接、timer/watcher/cache 或默认 Edge 成本。18-package clean build/test 全绿，AI 229 pass/3 条件 skip、backend 1,207 pass/2 条件 skip，四项架构审计零 finding；14 档 Local artifact 全通过，默认 Edge/Standalone 为 2,589,890/2,589,968 bytes。PostgreSQL 18.4 arm64 HA 130/130、timeline `1→2`，首次执行只读两次日志、密文不含敏感 fixture，提升后 exact replay 零日志读取；报告 SHA-256 为 `d525a303696e178d777b021b376729bd2c5382fb5eb7bc98466a2b79d3940517`，独立审计与 Docker 清理通过。
 - D-317/ADR-0409（已接受）：已解锁的 Cluster failure-diagnosis Model Step 现在从 durable encrypted Tool completion 重开受信日志投影，经 ADR-0405 builder 和既有 Model Gateway 执行；只有显式安装的 Copilot success sink 可以接管成功返回。Copilot `GenerateResult` 使用独立 AES-256-GCM Artifact，绑定 plan、Tool completion、egress evidence 与 Model identity，公开 reference、ModelInvocation completion、RunEvent 和审计均不含明文。通用 `DurableModelInvocationCoordinator` 已改为领域无关的 `ModelInvocationAtomicSuccess<TReference>`，消除对 Plugin Prompt Artifact 的反向依赖；Plugin Prompt 通过 adapter 保持兼容。`pg-9020` 在一个 SERIALIZABLE 事务中原子提交 ciphertext、Model completion、StepRun/Event 与 usage/pricing/quota settlement，再由可重放 finalization 事务把 diagnosis Run 推进为 `succeeded|failed|timed_out`；两事务间崩溃只补 finalization，existing start/completion/finalization replay 均不重复调用 Provider。当前仍不自动终态化 Tool failure、日志 missing/retired、Model admission 前 deadline/cancel，也不把 `outcome_unknown` 冒充失败；Cluster 专用 output projected keyring 与产品 composition 完成前该入口保持不可达。实现仍在既有 18 个 package 的嵌套领域目录内，不新增进程、队列、timer/watcher/cache 或默认 Edge 成本。最终 AI 233 pass/3 条件 skip、18-package clean build/test 与 backend 1,207 pass/2 条件 skip/0 fail，四项架构审计零 finding；workspace 无单文件或浅平 package，AI 183 个源码中 182 个位于嵌套目录。14 档 Local Profile artifact 全部通过，默认 Edge/Standalone 为 2,589,890/2,589,968 bytes，Edge/Standalone AI 为 3,061,009/3,061,099 bytes。PostgreSQL 18.6 arm64 HA 130/130、timeline `1→2`，报告 SHA-256 为 `8401634f30635b45bfb583b02e94ac41f023bf8a0bdbcfd9744ebf459ab0d8f8`，独立证据审计与 Docker 零残留。
diff --git a/docs/adr/ADR-0411-default-off-cluster-copilot-composition.md b/docs/adr/ADR-0411-default-off-cluster-copilot-composition.md
new file mode 100644
index 00000000..340b622d
--- /dev/null
+++ b/docs/adr/ADR-0411-default-off-cluster-copilot-composition.md
@@ -0,0 +1,83 @@
+# ADR-0411：默认关闭的 Cluster Copilot Failure Diagnosis Composition
+
+- 状态：Accepted
+- 日期：2026-08-15
+- 关联 RFC：QL-RFC-0001 D-319、Phase 2
+- 关联 ADR：ADR-0407、ADR-0408、ADR-0409、ADR-0410
+
+## 问题
+
+ADR-0407 至 ADR-0410 已分别建立 diagnosis admission、Trusted Tool execution、Model execution
+和独立 output key authority，但它们仍只在测试与 HA ceremony 中手工组装。若直接再启动一套 Model
+Gateway，会为每个 replica 复制 PostgreSQL Pool、Provider client、恢复扫描和并发预算；这对小型集群
+不合理，也会让 Prompt 与 Copilot 绕过同一模型出口限额。若直接开放 HTTP route，则 Tool failure、日志
+missing/retired、Model admission 前取消以及 outcome-unknown 尚未终态化，产品会暴露无法收敛的 Run。
+
+## 决策
+
+1. Copilot 只在既有显式 `ql3-cluster-control-ai` 进程中装配，并由独立
+   `QL3_CLUSTER_AI_COPILOT_ENABLED=true` 开关启用。默认 Cluster、Edge、Standalone 和仅 Prompt 的
+   Cluster AI 均不读取 Copilot 配置、keyring 或 Artifact authority。
+2. Prompt 与 Copilot 共享一个 PostgreSQL runtime Pool、一个 Model Gateway、同一 Provider authority、
+   recovery pass、pricing/quota ledger 和 `maxConcurrent` 预算。新增有界 successful-completion router，
+   只把一次已开始的 invocation 交给声明该 invocation 的 durable sink；不得复制 Gateway 或隐藏队列。
+3. Copilot Model execution 依赖 `generate()` 与 `supportsSuccessfulCompletionSink()` 的窄结构端口，不依赖
+   `BoundedModelGateway` 具体类，使 production Profile 的 drain/active-operation capability 可以直接注入，
+   同时保留 exact sink identity 检查。
+4. Cluster Copilot application service 从当前 PostgreSQL Run、latest Attempt、Project Tool snapshot 和
+   Policy 派生计划；调用者不能提供 Attempt、Artifact、Tool binding、Policy fence、key ID、nonce、
+   `plannedAtMs` 或内部 Run/Step/ModelInvocation identity。模型与 egress policy 来自部署者的 canonical
+   read-only配置，而不是请求体。
+5. diagnosis admission 先持久化 exact plan/Run/Step ledger，再物化可重建的加密 Tool invocation Artifact。
+   replay 使用 durable plan、historical invocation key 和域分离确定性 nonce 修复 admission→Artifact
+   crash window；只有 Artifact exact replay 成功后才允许 Tool execution。密钥副本使用后必须清零。
+6. Tool execution 复用同一 PostgreSQL repository、current snapshot、Project Policy 与 Worker Artifact
+   range reader；Model execution复用同一 Gateway，并由 ADR-0410 output keyring 原子落盘 ciphertext。
+   invocation、Tool result 与 Model output keyring 继续是三个不可互换的域。
+7. composition 能力在进程内保持 caller-driven、无 timer、watcher、队列或后台扫描。当前 Gate 不注册
+   HTTP/CLI/UI/MCP route；只有下一 Gate 完成所有非成功路径的 durable terminalization/recovery 后，
+   才能把该能力接入认证产品面。
+8. Kubernetes 以独立可选 component 投影 canonical Copilot 配置和三个 read-only keyring；它必须与
+   `cluster-ai` 以及可读 Worker Artifact storage 一起使用，不新增 Pod、ServiceAccount 权限或 sidecar。
+
+## 被否决方案
+
+1. **为 Copilot 再启动 Gateway/Pool**：资源翻倍并拆散全局并发、quota 和 Provider 出口约束。
+2. **让 Gateway 依赖具体业务 sink**：把通用模型边界反向耦合到 Prompt/Copilot 产品域。
+3. **由请求提交完整执行计划**：把 source fence、Tool binding、egress policy 和内部 identity 交给不可信边界。
+4. **先开放 route、以后补失败收敛**：会产生用户可见但永久 running/pending 的 diagnosis Run。
+5. **把三个 keyring 合并**：轮换、退役与泄漏半径跨越 Tool 输入、Tool 输出和模型输出域。
+6. **新增 workspace package**：composition 没有独立进程或依赖闭包，薄包会恶化已有 package 粒度。
+
+## 验证标准
+
+1. completion router 证明 Prompt/Copilot 精确分发、未知 invocation 不落盘、重复/扩展 sink 拒绝。
+2. 默认关闭时不读取 Copilot config、keyring、Worker Artifact 或新增 PostgreSQL authority。
+3. composition 测试覆盖 server-derived source/snapshot/Policy、admission→Artifact crash repair、Tool→Model
+   成功链、exact replay、key rotation、配置/authority 缺失和有序 drain。
+4. AI、Cluster Control、18-package clean build/test、backend、四项架构审计和 14 档 Local artifact 全通过。
+5. PostgreSQL 组合证据覆盖真实 repository 上的 admission、Tool completion、Model ciphertext、finalization
+   与 exact replay；本 Gate 不新增 migration、schema、role 或 SQL privilege。
+
+## 当前验证
+
+1. successful-completion router 与 Cluster Copilot application/composition 定向测试全部通过；AI 完整测试
+   238 pass/3 条件 skip，Cluster Control 完整测试 240 pass/2 条件 skip。
+2. 18-package clean build/test 全部通过；backend 1,207 pass/2 条件 skip/0 fail。package boundary、
+   dependency、Edge import 与 Cluster deployment 四项审计均为 compatible、零 finding。
+3. workspace 仍为 18 个 package，无 single-source 或 shallow-source package；AI 187 个源码中 186 个、
+   Cluster Control 59 个源码中 57 个位于嵌套领域目录。新增 composition 没有制造薄 package 或根层平铺。
+4. 14 档 Local Profile artifact 全部通过。默认 Edge/Standalone 保持
+   2,589,890/2,589,968 bytes；Edge/Standalone AI 为 3,064,454/3,064,544 bytes，均未引入 Cluster-only
+   composition，且分别保有 1,604,414/1,604,336 与 2,178,426/2,178,336 bytes 体积余量。
+5. PostgreSQL 18.6 arm64 HA 130/130、timeline `1→2`，报告 SHA-256 为
+   `981299b454dce5541e9596450b85816dc40559cba8dc42adf3d5fea571c3d3a6`。本 Gate 不新增
+   migration、schema、role、SQL privilege 或 HA 拓扑；真实 repository 的 admission、Tool completion、
+   Model ciphertext、finalization 与 exact replay 沿用同一受审 authority，Docker 门禁与清理均通过。
+
+## 后续门禁
+
+1. 为 Tool `failed|timed_out`、日志 `missing|retired|pending`、deadline/cancel 和 Model
+   `outcome_unknown` 建立有界 durable terminalization/recovery。
+2. 完成后再增加经 authentication、Policy、audit、request identity 和 source fence 保护的 Cluster API，
+   随后复用该 capability 提供 CLI/UI/MCP，而不是建立旁路执行器。
diff --git a/docs/adr/README.md b/docs/adr/README.md
index 33f0b337..ad59d386 100644
--- a/docs/adr/README.md
+++ b/docs/adr/README.md
@@ -414,6 +414,7 @@
 | [ADR-0408](./ADR-0408-cluster-copilot-failure-diagnosis-tool-execution.md)                         | Cluster Copilot Failure Diagnosis Tool Execution 与原子 Model 解锁                                                                                    | Accepted |
 | [ADR-0409](./ADR-0409-cluster-copilot-failure-diagnosis-model-execution.md)                        | Cluster Copilot Failure Diagnosis Model Execution、密文输出与 Run 终态化                                                                               | Accepted |
 | [ADR-0410](./ADR-0410-cluster-copilot-failure-diagnosis-output-key-authority.md)                   | Cluster Copilot Failure Diagnosis Output Projected Key Authority                                                                                        | Accepted |
+| [ADR-0411](./ADR-0411-default-off-cluster-copilot-composition.md)                                  | 默认关闭的 Cluster Copilot Failure Diagnosis Composition                                                                                                  | Accepted |
 
 ## 规则
 
diff --git a/packages/ql3-ai/package.json b/packages/ql3-ai/package.json
index 5c08cc7d..ca0d989c 100644
--- a/packages/ql3-ai/package.json
+++ b/packages/ql3-ai/package.json
@@ -55,6 +55,11 @@
       "require": "./dist/copilot/failure-diagnosis/modelExecution.js",
       "default": "./dist/copilot/failure-diagnosis/modelExecution.js"
     },
+    "./failure-diagnosis-application": {
+      "types": "./dist/copilot/failure-diagnosis/failureDiagnosisApplication.d.ts",
+      "require": "./dist/copilot/failure-diagnosis/failureDiagnosisApplication.js",
+      "default": "./dist/copilot/failure-diagnosis/failureDiagnosisApplication.js"
+    },
     "./postgres-failure-diagnosis-model-execution-storage": {
       "types": "./dist/copilot/failure-diagnosis/postgresModelExecutionRepository.d.ts",
       "require": "./dist/copilot/failure-diagnosis/postgresModelExecutionRepository.js",
diff --git a/packages/ql3-ai/src/copilot/failure-diagnosis/application/contracts.ts b/packages/ql3-ai/src/copilot/failure-diagnosis/application/contracts.ts
new file mode 100644
index 00000000..151ea73c
--- /dev/null
+++ b/packages/ql3-ai/src/copilot/failure-diagnosis/application/contracts.ts
@@ -0,0 +1,59 @@
+import type { SecurityPrincipal } from '@qinglong/runtime-core/security';
+
+import type { CopilotFailureDiagnosisAdmissionReceipt } from '../admission/contracts';
+import type { CopilotFailureDiagnosisModelExecutionResult } from '../model-execution/coordinator';
+import type { CopilotFailureDiagnosisToolExecutionResult } from '../tool-execution/contracts';
+
+export const MAX_ACTIVE_COPILOT_FAILURE_DIAGNOSIS_APPLICATION_REQUESTS = 64;
+
+export interface ExecuteCopilotFailureDiagnosisApplicationCommand {
+  readonly requestId: string;
+  readonly traceId: string;
+  readonly projectId: string;
+  readonly sourceRunId: string;
+  readonly principal: Readonly<SecurityPrincipal>;
+}
+
+export interface ExecuteCopilotFailureDiagnosisApplicationResult {
+  readonly admissionStatus: 'created' | 'existing';
+  readonly admission: Readonly<CopilotFailureDiagnosisAdmissionReceipt>;
+  readonly tool: Readonly<CopilotFailureDiagnosisToolExecutionResult>;
+  readonly model: Readonly<CopilotFailureDiagnosisModelExecutionResult> | null;
+  readonly terminalizationRequired: boolean;
+}
+
+export class InvalidCopilotFailureDiagnosisApplicationError extends TypeError {
+  readonly code = 'COPILOT_FAILURE_DIAGNOSIS_APPLICATION_INVALID';
+
+  constructor(message: string) {
+    super(`Copilot failure diagnosis application is invalid: ${message}`);
+    this.name = 'InvalidCopilotFailureDiagnosisApplicationError';
+  }
+}
+
+export class CopilotFailureDiagnosisApplicationConflictError extends Error {
+  readonly code = 'COPILOT_FAILURE_DIAGNOSIS_APPLICATION_CONFLICT';
+
+  constructor(message = 'the durable diagnosis request changed') {
+    super(`Copilot failure diagnosis application conflicts: ${message}`);
+    this.name = 'CopilotFailureDiagnosisApplicationConflictError';
+  }
+}
+
+export class CopilotFailureDiagnosisApplicationUnavailableError extends Error {
+  readonly code = 'COPILOT_FAILURE_DIAGNOSIS_APPLICATION_UNAVAILABLE';
+
+  constructor(options?: ErrorOptions) {
+    super('Copilot failure diagnosis application is unavailable', options);
+    this.name = 'CopilotFailureDiagnosisApplicationUnavailableError';
+  }
+}
+
+export class CopilotFailureDiagnosisApplicationBusyError extends Error {
+  readonly code = 'COPILOT_FAILURE_DIAGNOSIS_APPLICATION_BUSY';
+
+  constructor() {
+    super('Copilot failure diagnosis application request budget is exhausted');
+    this.name = 'CopilotFailureDiagnosisApplicationBusyError';
+  }
+}
diff --git a/packages/ql3-ai/src/copilot/failure-diagnosis/application/service.ts b/packages/ql3-ai/src/copilot/failure-diagnosis/application/service.ts
new file mode 100644
index 00000000..087c899a
--- /dev/null
+++ b/packages/ql3-ai/src/copilot/failure-diagnosis/application/service.ts
@@ -0,0 +1,572 @@
+import { Buffer } from 'node:buffer';
+import { createHash, createHmac } from 'node:crypto';
+
+import {
+  BUILTIN_RUN_LOG_EXCERPT_TOOL,
+  createBuiltInRunLogExcerptToolHandlerBinding,
+} from '@qinglong/runtime-core/builtin-run-log-excerpt-tool';
+import type { RunRepositoryReader } from '@qinglong/runtime-core/run-repository';
+import type { ToolPolicyAuthorizer } from '@qinglong/runtime-core/tool-registry';
+import {
+  prepareToolInvocation,
+} from '@qinglong/runtime-core/tool-registry';
+import type { ProjectToolDefinitionSnapshotRepository } from '@qinglong/runtime-core/project-tool-definition-snapshot';
+import { projectToolDefinitionRegistry } from '@qinglong/runtime-core/project-tool-definition-snapshot';
+import {
+  createToolInvocationInputArtifact,
+  createToolInvocationPreviewArtifact,
+  type ToolInvocationArtifactKeyProvider,
+  type ToolInvocationArtifactRepository,
+  type ToolInvocationPreviewDocument,
+} from '@qinglong/runtime-core/tool-invocation-artifact';
+import {
+  TrustedToolHandlerBindingRegistry,
+  createTrustedToolInvocationPlan,
+} from '@qinglong/runtime-core/trusted-tool-invocation';
+
+import { MAX_MODEL_INVOCATION_MS } from '../../../model-gateway/model';
+import {
+  prepareCopilotFailureDiagnosisExecution,
+} from '../admission/plan';
+import type {
+  CopilotFailureDiagnosisAdmissionRepository,
+  CopilotFailureDiagnosisExecutionPlan,
+  PrepareCopilotFailureDiagnosisModelIntent,
+} from '../admission/contracts';
+import {
+  executeCopilotFailureDiagnosisTool,
+  type CopilotFailureDiagnosisToolExecutionDependencies,
+} from '../tool-execution/coordinator';
+import {
+  executeCopilotFailureDiagnosisModel,
+  type CopilotFailureDiagnosisModelExecutionDependencies,
+} from '../model-execution/coordinator';
+import {
+  CopilotFailureDiagnosisApplicationBusyError,
+  CopilotFailureDiagnosisApplicationConflictError,
+  CopilotFailureDiagnosisApplicationUnavailableError,
+  InvalidCopilotFailureDiagnosisApplicationError,
+  MAX_ACTIVE_COPILOT_FAILURE_DIAGNOSIS_APPLICATION_REQUESTS,
+  type ExecuteCopilotFailureDiagnosisApplicationCommand,
+  type ExecuteCopilotFailureDiagnosisApplicationResult,
+} from './contracts';
+
+const ID_PATTERN = /^[A-Za-z0-9][A-Za-z0-9._:-]{0,127}$/;
+const RUN_ID_PATTERN = /^[A-Za-z0-9][A-Za-z0-9._:-]{0,35}$/;
+const NONCE_DOMAIN = Buffer.from(
+  'qinglong/copilot-failure-diagnosis-tool-invocation-nonce@v1\0',
+  'utf8',
+);
+const IDENTITY_DOMAIN = Buffer.from(
+  'qinglong/copilot-failure-diagnosis-application-identity@v1\0',
+  'utf8',
+);
+
+export interface CopilotFailureDiagnosisApplicationDependencies {
+  readonly admissions: CopilotFailureDiagnosisAdmissionRepository;
+  readonly snapshots: Pick<ProjectToolDefinitionSnapshotRepository, 'findCurrent'>;
+  readonly runs: Pick<
+    RunRepositoryReader,
+    'findRunById' | 'findLatestAttemptByRunId'
+  >;
+  readonly artifacts: ToolInvocationArtifactRepository;
+  readonly invocationKeys: Pick<
+    ToolInvocationArtifactKeyProvider,
+    'active' | 'resolve'
+  >;
+  readonly authorizer: ToolPolicyAuthorizer;
+  readonly tool: CopilotFailureDiagnosisToolExecutionDependencies;
+  readonly model: CopilotFailureDiagnosisModelExecutionDependencies;
+  readonly executeTool: typeof executeCopilotFailureDiagnosisTool;
+  readonly executeModel: typeof executeCopilotFailureDiagnosisModel;
+  readonly modelIntent: Readonly<PrepareCopilotFailureDiagnosisModelIntent>;
+  readonly executionTimeoutMs: number;
+  readonly now?: () => number;
+  readonly nonceFactory?: (input: Readonly<{
+    key: Uint8Array;
+    keyId: string;
+    requestId: string;
+    projectId: string;
+    sourceRunId: string;
+    invocationActionDigest: string;
+  }>) => Uint8Array;
+}
+
+interface ActiveRequest {
+  readonly digest: string;
+  readonly promise: Promise<
+    Readonly<ExecuteCopilotFailureDiagnosisApplicationResult>
+  >;
+}
+
+function invalid(message: string): never {
+  throw new InvalidCopilotFailureDiagnosisApplicationError(message);
+}
+
+function unavailable(cause?: unknown): never {
+  throw new CopilotFailureDiagnosisApplicationUnavailableError({
+    cause: cause instanceof Error ? cause : undefined,
+  });
+}
+
+function digest(value: unknown): string {
+  return createHash('sha256').update(JSON.stringify(value)).digest('hex');
+}
+
+function identity(prefix: string, requestId: string): string {
+  return `${prefix}:${createHash('sha256')
+    .update(IDENTITY_DOMAIN)
+    .update(prefix)
+    .update('\0')
+    .update(requestId)
+    .digest('hex')
+    .slice(0, 32)}`;
+}
+
+function preview(
+  sourceRunId: string,
+  sourceAttemptId: string,
+): Readonly<ToolInvocationPreviewDocument> {
+  return Object.freeze({
+    title: 'Diagnose failed Run',
+    summary: 'Read one bounded, redacted and untrusted execution log excerpt',
+    fields: Object.freeze([
+      Object.freeze({
+        kind: 'identifier' as const,
+        label: 'Run',
+        value: sourceRunId,
+      }),
+      Object.freeze({
+        kind: 'identifier' as const,
+        label: 'Attempt',
+        value: sourceAttemptId,
+      }),
+    ]),
+    warnings: Object.freeze(['potentially_sensitive_output']),
+  });
+}
+
+function defaultNonce(input: Readonly<{
+  key: Uint8Array;
+  keyId: string;
+  requestId: string;
+  projectId: string;
+  sourceRunId: string;
+  invocationActionDigest: string;
+}>): Uint8Array {
+  const derived = createHmac('sha256', Buffer.from(input.key))
+    .update(NONCE_DOMAIN)
+    .update(
+      JSON.stringify({
+        keyId: input.keyId,
+        requestId: input.requestId,
+        projectId: input.projectId,
+        sourceRunId: input.sourceRunId,
+        invocationActionDigest: input.invocationActionDigest,
+      }),
+    )
+    .digest();
+  try {
+    return Buffer.from(derived.subarray(0, 12));
+  } finally {
+    derived.fill(0);
+  }
+}
+
+function normalizeCommand(
+  value: ExecuteCopilotFailureDiagnosisApplicationCommand,
+): Readonly<ExecuteCopilotFailureDiagnosisApplicationCommand> {
+  if (
+    !value ||
+    typeof value !== 'object' ||
+    Array.isArray(value) ||
+    Object.keys(value).sort().join('\0') !==
+      ['principal', 'projectId', 'requestId', 'sourceRunId', 'traceId'].join(
+        '\0',
+      ) ||
+    !ID_PATTERN.test(value.requestId) ||
+    !ID_PATTERN.test(value.traceId) ||
+    !ID_PATTERN.test(value.projectId) ||
+    !RUN_ID_PATTERN.test(value.sourceRunId) ||
+    !value.principal ||
+    typeof value.principal !== 'object' ||
+    Array.isArray(value.principal)
+  ) {
+    return invalid('command is invalid');
+  }
+  return Object.freeze({
+    requestId: value.requestId,
+    traceId: value.traceId,
+    projectId: value.projectId,
+    sourceRunId: value.sourceRunId,
+    principal: value.principal,
+  });
+}
+
+function assertDependencies(
+  value: CopilotFailureDiagnosisApplicationDependencies,
+): void {
+  if (
+    !value ||
+    typeof value !== 'object' ||
+    Array.isArray(value) ||
+    typeof value.admissions?.findByRequestId !== 'function' ||
+    typeof value.admissions?.findPlanByRequestId !== 'function' ||
+    typeof value.admissions?.admit !== 'function' ||
+    typeof value.snapshots?.findCurrent !== 'function' ||
+    typeof value.runs?.findRunById !== 'function' ||
+    typeof value.runs?.findLatestAttemptByRunId !== 'function' ||
+    typeof value.artifacts?.put !== 'function' ||
+    typeof value.invocationKeys?.active !== 'function' ||
+    typeof value.invocationKeys?.resolve !== 'function' ||
+    typeof value.authorizer?.authorize !== 'function' ||
+    typeof value.executeTool !== 'function' ||
+    typeof value.executeModel !== 'function' ||
+    !value.tool ||
+    !value.model ||
+    !value.modelIntent ||
+    typeof value.modelIntent !== 'object' ||
+    !Number.isSafeInteger(value.executionTimeoutMs) ||
+    value.executionTimeoutMs < 1 ||
+    value.executionTimeoutMs > MAX_MODEL_INVOCATION_MS ||
+    (value.now !== undefined && typeof value.now !== 'function') ||
+    (value.nonceFactory !== undefined &&
+      typeof value.nonceFactory !== 'function')
+  ) {
+    return invalid('dependencies are invalid');
+  }
+  if (
+    value.tool.admissions !== value.admissions ||
+    value.tool.snapshots !== value.snapshots ||
+    value.tool.runs !== value.runs ||
+    value.tool.artifacts !== value.artifacts ||
+    value.tool.invocationKeys !== value.invocationKeys ||
+    value.model.admissions !== value.admissions ||
+    value.model.unlocks !== value.tool.unlocks
+  ) {
+    return invalid('dependency authorities are not shared');
+  }
+}
+
+function sameSubject(
+  left: Readonly<{ type: string; id: string }>,
+  right: Readonly<{ type: string; id: string }>,
+): boolean {
+  return left.type === right.type && left.id === right.id;
+}
+
+function sameModelIntent(
+  plan: Readonly<CopilotFailureDiagnosisExecutionPlan>,
+  configured: Readonly<PrepareCopilotFailureDiagnosisModelIntent>,
+): boolean {
+  return (
+    plan.model.provider === configured.provider &&
+    plan.model.model === configured.model &&
+    plan.model.modelBoundary === configured.modelBoundary &&
+    plan.model.responseLanguage === configured.responseLanguage &&
+    plan.model.maxOutputTokens === configured.maxOutputTokens &&
+    JSON.stringify(plan.model.egressPolicy) ===
+      JSON.stringify(configured.egressPolicy)
+  );
+}
+
+function nonceInput(
+  plan: Readonly<CopilotFailureDiagnosisExecutionPlan>,
+  key: Uint8Array,
+) {
+  return Object.freeze({
+    key,
+    keyId: plan.tool.invocationArtifact.keyId,
+    requestId: plan.requestId,
+    projectId: plan.projectId,
+    sourceRunId: plan.source.runId,
+    invocationActionDigest: plan.tool.invocationActionDigest,
+  });
+}
+
+export class CopilotFailureDiagnosisApplicationService {
+  readonly #dependencies: CopilotFailureDiagnosisApplicationDependencies;
+  readonly #active = new Map<string, ActiveRequest>();
+
+  constructor(dependencies: CopilotFailureDiagnosisApplicationDependencies) {
+    assertDependencies(dependencies);
+    this.#dependencies = dependencies;
+  }
+
+  execute(
+    commandValue: ExecuteCopilotFailureDiagnosisApplicationCommand,
+  ): Promise<Readonly<ExecuteCopilotFailureDiagnosisApplicationResult>> {
+    const command = normalizeCommand(commandValue);
+    const commandDigest = digest(command);
+    const active = this.#active.get(command.requestId);
+    if (active) {
+      if (active.digest !== commandDigest) {
+        throw new CopilotFailureDiagnosisApplicationConflictError();
+      }
+      return active.promise;
+    }
+    if (
+      this.#active.size >=
+      MAX_ACTIVE_COPILOT_FAILURE_DIAGNOSIS_APPLICATION_REQUESTS
+    ) {
+      throw new CopilotFailureDiagnosisApplicationBusyError();
+    }
+    const promise = this.#execute(command).finally(() => {
+      this.#active.delete(command.requestId);
+    });
+    this.#active.set(command.requestId, { digest: commandDigest, promise });
+    return promise;
+  }
+
+  async #execute(
+    command: Readonly<ExecuteCopilotFailureDiagnosisApplicationCommand>,
+  ): Promise<Readonly<ExecuteCopilotFailureDiagnosisApplicationResult>> {
+    const existing = await this.#dependencies.admissions.findPlanByRequestId(
+      command.requestId,
+    );
+    let plan: Readonly<CopilotFailureDiagnosisExecutionPlan>;
+    let admissionStatus: 'created' | 'existing';
+    let admission;
+    if (existing) {
+      if (
+        existing.projectId !== command.projectId ||
+        existing.source.runId !== command.sourceRunId ||
+        existing.traceId !== command.traceId ||
+        !sameSubject(existing.requestedBySubject, command.principal.subject) ||
+        !sameModelIntent(existing, this.#dependencies.modelIntent)
+      ) {
+        throw new CopilotFailureDiagnosisApplicationConflictError();
+      }
+      plan = existing;
+      const admitted = await this.#dependencies.admissions.admit(plan);
+      admissionStatus = admitted.status;
+      admission = admitted.receipt;
+      await this.#materializeArtifacts(plan);
+    } else {
+      const prepared = await this.#prepare(command);
+      plan = prepared.plan;
+      const admitted = await this.#dependencies.admissions.admit(plan);
+      admissionStatus = admitted.status;
+      admission = admitted.receipt;
+      try {
+        await this.#dependencies.artifacts.put(
+          prepared.inputArtifact,
+          prepared.previewArtifact,
+        );
+      } catch (cause) {
+        throw new CopilotFailureDiagnosisApplicationUnavailableError({
+          cause: cause instanceof Error ? cause : undefined,
+        });
+      }
+    }
+    const tool = await this.#dependencies.executeTool(
+      {
+        requestId: plan.requestId,
+        principal: command.principal,
+        authorizer: this.#dependencies.authorizer,
+      },
+      this.#dependencies.tool,
+    );
+    if (tool.outcome !== 'succeeded') {
+      return Object.freeze({
+        admissionStatus,
+        admission,
+        tool,
+        model: null,
+        terminalizationRequired: true,
+      });
+    }
+    const model = await this.#dependencies.executeModel(
+      plan.requestId,
+      this.#dependencies.model,
+    );
+    return Object.freeze({
+      admissionStatus,
+      admission,
+      tool,
+      model,
+      terminalizationRequired: false,
+    });
+  }
+
+  async #prepare(
+    command: Readonly<ExecuteCopilotFailureDiagnosisApplicationCommand>,
+  ) {
+    const now = this.#clock();
+    let run;
+    let attempt;
+    let snapshotRecord;
+    try {
+      [run, attempt, snapshotRecord] = await Promise.all([
+        this.#dependencies.runs.findRunById(command.sourceRunId),
+        this.#dependencies.runs.findLatestAttemptByRunId(command.sourceRunId),
+        this.#dependencies.snapshots.findCurrent(command.projectId),
+      ]);
+    } catch (cause) {
+      return unavailable(cause);
+    }
+    if (
+      !run ||
+      !attempt ||
+      !snapshotRecord ||
+      run.projectId !== command.projectId ||
+      attempt.runId !== run.id ||
+      !['failed', 'timed_out'].includes(run.status) ||
+      !['failed', 'timed_out', 'lost'].includes(attempt.status) ||
+      (run.status === 'failed' &&
+        !['failed', 'lost'].includes(attempt.status)) ||
+      (run.status === 'timed_out' && attempt.status !== 'timed_out') ||
+      !Number.isSafeInteger(attempt.finishedAtMs) ||
+      typeof attempt.logArtifactId !== 'string'
+    ) {
+      throw new CopilotFailureDiagnosisApplicationConflictError(
+        'source Run is not an exact diagnosable terminal fence',
+      );
+    }
+    const snapshot = snapshotRecord.snapshot;
+    const binding = createBuiltInRunLogExcerptToolHandlerBinding(snapshot, [
+      'cluster-control',
+    ]);
+    const bindings = new TrustedToolHandlerBindingRegistry(snapshot, [binding]);
+    const invocation = await prepareToolInvocation(
+      projectToolDefinitionRegistry(snapshot),
+      {
+        projectId: command.projectId,
+        principal: command.principal,
+        nowMs: now,
+        tool: BUILTIN_RUN_LOG_EXCERPT_TOOL,
+        input: { runId: run.id, attemptId: attempt.id },
+      },
+      this.#dependencies.authorizer,
+    );
+    if (invocation.status !== 'ready') {
+      throw new CopilotFailureDiagnosisApplicationConflictError(
+        'Tool admission is not ready',
+      );
+    }
+    const key = await this.#dependencies.invocationKeys.active();
+    try {
+      const baseIdentity = identity('cda', command.requestId);
+      const nonce = (
+        this.#dependencies.nonceFactory ?? defaultNonce
+      )({
+        key: key.key,
+        keyId: key.keyId,
+        requestId: command.requestId,
+        projectId: command.projectId,
+        sourceRunId: run.id,
+        invocationActionDigest: invocation.actionDigest,
+      });
+      const tool = createTrustedToolInvocationPlan(bindings, invocation, {
+        actionRef: baseIdentity,
+        profile: 'cluster-control',
+        preview: preview(run.id, attempt.id),
+        inputArtifactId: identity('cdia', command.requestId),
+        previewArtifactId: identity('cdpa', command.requestId),
+        artifactKeyId: key.keyId,
+        artifactKey: key.key,
+        artifactNonce: nonce,
+        sealedAtMs: now,
+      });
+      nonce.fill(0);
+      const plan = prepareCopilotFailureDiagnosisExecution({
+        requestId: command.requestId,
+        traceId: command.traceId,
+        source: {
+          runId: run.id,
+          runVersion: run.version,
+          runStatus: run.status as 'failed' | 'timed_out',
+          attemptId: attempt.id,
+          attemptStatus: attempt.status as 'failed' | 'timed_out' | 'lost',
+          attemptFinishedAtMs: attempt.finishedAtMs!,
+          logArtifactId: attempt.logArtifactId,
+        },
+        toolPlan: tool.plan,
+        bindings,
+        model: this.#dependencies.modelIntent,
+        deadlineAtMs: now + this.#dependencies.executionTimeoutMs,
+        plannedAtMs: now,
+      });
+      return Object.freeze({
+        plan,
+        inputArtifact: tool.inputArtifact,
+        previewArtifact: tool.previewArtifact,
+      });
+    } finally {
+      key.key.fill(0);
+    }
+  }
+
+  async #materializeArtifacts(
+    plan: Readonly<CopilotFailureDiagnosisExecutionPlan>,
+  ): Promise<void> {
+    const material = await this.#dependencies.invocationKeys.resolve(
+      plan.tool.invocationArtifact.keyId,
+    );
+    if (!material || material.keyId !== plan.tool.invocationArtifact.keyId) {
+      return unavailable();
+    }
+    try {
+      const nonce = (
+        this.#dependencies.nonceFactory ?? defaultNonce
+      )(nonceInput(plan, material.key));
+      const inputArtifact = createToolInvocationInputArtifact(
+        {
+          artifactId: plan.tool.invocationArtifact.artifactId,
+          projectId: plan.projectId,
+          actionRef: plan.tool.actionRef,
+          requestedBy: plan.requestedBySubject,
+          tool: BUILTIN_RUN_LOG_EXCERPT_TOOL,
+          input: {
+            attemptId: plan.source.attemptId,
+            runId: plan.source.runId,
+          },
+          inputDigest: plan.tool.invocationArtifact.inputDigest,
+          invocationActionDigest: plan.tool.invocationActionDigest,
+          keyId: material.keyId,
+          key: material.key,
+          sealedAtMs: plan.tool.sealedAtMs,
+        },
+        () => nonce,
+      );
+      nonce.fill(0);
+      const previewArtifact = createToolInvocationPreviewArtifact({
+        artifactId: plan.tool.previewArtifact.artifactId,
+        projectId: plan.projectId,
+        actionRef: plan.tool.actionRef,
+        actionDigest: plan.tool.actionDigest,
+        redactionContractDigest:
+          plan.tool.previewArtifact.redactionContractDigest,
+        preview: preview(plan.source.runId, plan.source.attemptId),
+        sealedAtMs: plan.tool.sealedAtMs,
+      });
+      if (
+        inputArtifact.artifactDigest !==
+          plan.tool.invocationArtifact.artifactDigest ||
+        previewArtifact.artifactDigest !==
+          plan.tool.previewArtifact.artifactDigest
+      ) {
+        throw new CopilotFailureDiagnosisApplicationConflictError(
+          'durable Tool Artifact references cannot be reconstructed',
+        );
+      }
+      await this.#dependencies.artifacts.put(inputArtifact, previewArtifact);
+    } finally {
+      material.key.fill(0);
+    }
+  }
+
+  #clock(): number {
+    let value: number;
+    try {
+      value = (this.#dependencies.now ?? Date.now)();
+    } catch (cause) {
+      return unavailable(cause);
+    }
+    if (!Number.isSafeInteger(value) || value < 0) return invalid('clock');
+    if (value + this.#dependencies.executionTimeoutMs > Number.MAX_SAFE_INTEGER) {
+      return invalid('deadline overflows');
+    }
+    return value;
+  }
+}
diff --git a/packages/ql3-ai/src/copilot/failure-diagnosis/failureDiagnosisApplication.ts b/packages/ql3-ai/src/copilot/failure-diagnosis/failureDiagnosisApplication.ts
new file mode 100644
index 00000000..f4329f5b
--- /dev/null
+++ b/packages/ql3-ai/src/copilot/failure-diagnosis/failureDiagnosisApplication.ts
@@ -0,0 +1,2 @@
+export * from './application/contracts';
+export * from './application/service';
diff --git a/packages/ql3-ai/src/copilot/failure-diagnosis/model-execution/coordinator.ts b/packages/ql3-ai/src/copilot/failure-diagnosis/model-execution/coordinator.ts
index 5756b010..977a0874 100644
--- a/packages/ql3-ai/src/copilot/failure-diagnosis/model-execution/coordinator.ts
+++ b/packages/ql3-ai/src/copilot/failure-diagnosis/model-execution/coordinator.ts
@@ -5,7 +5,10 @@ import {
   type TrustedToolSuccessCompletionReadDependencies,
 } from '@qinglong/runtime-core/trusted-tool-completion';
 
-import { BoundedModelGateway } from '../../../model-gateway/gateway';
+import type {
+  BoundedModelGateway,
+  ModelInvocationSuccessfulCompletionSink,
+} from '../../../model-gateway/gateway';
 import type { ModelInvocationRepository } from '../../../model-invocation/modelInvocation';
 import type { CopilotFailureDiagnosisToolExecutionAdmissionReader } from '../tool-execution/contracts';
 import type { CopilotFailureDiagnosisToolUnlockRepository } from '../tool-execution/contracts';
@@ -36,20 +39,26 @@ export interface CopilotFailureDiagnosisModelExecutionDependencies {
     CopilotFailureDiagnosisOutputCompletionRepository,
     'findCopilotFailureDiagnosisOutput'
   >;
-  readonly gateway: BoundedModelGateway;
+  readonly gateway: Pick<
+    BoundedModelGateway,
+    'generate' | 'supportsSuccessfulCompletionSink'
+  >;
   readonly successfulCompletion: CopilotFailureDiagnosisModelCompletionCoordinator;
   readonly finalizations: CopilotFailureDiagnosisFinalizationRepository;
 }
 
 export interface CopilotFailureDiagnosisToolResultReader {
-  open(startId: string): Promise<Readonly<TrustedToolSuccessCompletionResult>>;
+  open(
+    requestId: string,
+    startId: string,
+  ): Promise<Readonly<TrustedToolSuccessCompletionResult>>;
 }
 
 export function createCopilotFailureDiagnosisToolResultReader(
   dependencies: TrustedToolSuccessCompletionReadDependencies,
 ): CopilotFailureDiagnosisToolResultReader {
   return Object.freeze({
-    open: (startId: string) =>
+    open: (_requestId: string, startId: string) =>
       openTrustedToolSuccessCompletion(startId, dependencies),
   });
 }
@@ -97,7 +106,8 @@ function assertDependencies(
     typeof value.modelInvocations?.findStart !== 'function' ||
     typeof value.modelInvocations?.findCompletion !== 'function' ||
     typeof value.outputs?.findCopilotFailureDiagnosisOutput !== 'function' ||
-    !(value.gateway instanceof BoundedModelGateway) ||
+    typeof value.gateway?.generate !== 'function' ||
+    typeof value.gateway?.supportsSuccessfulCompletionSink !== 'function' ||
     typeof value.successfulCompletion?.begin !== 'function' ||
     typeof value.successfulCompletion?.reference !== 'function' ||
     typeof value.successfulCompletion?.end !== 'function' ||
@@ -215,7 +225,7 @@ export async function executeCopilotFailureDiagnosisModel(
     );
   }
 
-  const tool = await dependencies.toolResults.open(unlock.startId);
+  const tool = await dependencies.toolResults.open(requestId, unlock.startId);
   if (
     tool.completion.completionDigest !== unlock.toolCompletionDigest ||
     tool.completion.runId !== plan.runId ||
@@ -241,7 +251,7 @@ export async function executeCopilotFailureDiagnosisModel(
   });
   if (
     !dependencies.gateway.supportsSuccessfulCompletionSink(
-      dependencies.successfulCompletion,
+      dependencies.successfulCompletion as ModelInvocationSuccessfulCompletionSink,
     )
   ) {
     throw new InvalidCopilotFailureDiagnosisModelExecutionError(
diff --git a/packages/ql3-ai/src/model-gateway/gateway.ts b/packages/ql3-ai/src/model-gateway/gateway.ts
index cbe4188a..71cb770f 100644
--- a/packages/ql3-ai/src/model-gateway/gateway.ts
+++ b/packages/ql3-ai/src/model-gateway/gateway.ts
@@ -39,6 +39,12 @@ import {
   type ModelPriceCatalogResolver,
 } from '../pricing/pricing';
 
+export {
+  InvalidModelInvocationSuccessfulCompletionRouterError,
+  MAX_MODEL_INVOCATION_SUCCESSFUL_COMPLETION_SINKS,
+  ModelInvocationSuccessfulCompletionRouter,
+} from './successfulCompletionRouter';
+
 export const MAX_MODEL_GATEWAY_CONCURRENCY = 64;
 
 export class ModelProviderUnavailableError extends Error {
@@ -126,6 +132,9 @@ export interface BoundedModelGatewayOptions {
 }
 
 export interface ModelInvocationSuccessfulCompletionSink {
+  supportsSuccessfulCompletionSink?(
+    sink: ModelInvocationSuccessfulCompletionSink,
+  ): boolean;
   record(
     audit: Readonly<ModelInvocationAuditRecord>,
     result: Readonly<GenerateResult>,
@@ -372,7 +381,11 @@ export class BoundedModelGateway {
   supportsSuccessfulCompletionSink(
     sink: ModelInvocationSuccessfulCompletionSink,
   ): boolean {
-    return this.#successfulCompletion === sink;
+    const configured = this.#successfulCompletion;
+    return (
+      configured === sink ||
+      configured?.supportsSuccessfulCompletionSink?.(sink) === true
+    );
   }
 
   async #prepare(
diff --git a/packages/ql3-ai/src/model-gateway/successfulCompletionRouter.ts b/packages/ql3-ai/src/model-gateway/successfulCompletionRouter.ts
new file mode 100644
index 00000000..70a30a56
--- /dev/null
+++ b/packages/ql3-ai/src/model-gateway/successfulCompletionRouter.ts
@@ -0,0 +1,80 @@
+import type { ModelInvocationSuccessfulCompletionSink } from './gateway';
+import type {
+  GenerateResult,
+  ModelInvocationAuditRecord,
+  ModelInvocationAuditResult,
+} from './model';
+
+export const MAX_MODEL_INVOCATION_SUCCESSFUL_COMPLETION_SINKS = 8;
+
+export class InvalidModelInvocationSuccessfulCompletionRouterError extends TypeError {
+  readonly code = 'MODEL_INVOCATION_SUCCESSFUL_COMPLETION_ROUTER_INVALID';
+
+  constructor() {
+    super('Model invocation successful completion router is invalid');
+    this.name = 'InvalidModelInvocationSuccessfulCompletionRouterError';
+  }
+}
+
+/** Bounded dispatch for mutually exclusive durable output domains. */
+export class ModelInvocationSuccessfulCompletionRouter
+  implements ModelInvocationSuccessfulCompletionSink
+{
+  readonly #sinks: readonly ModelInvocationSuccessfulCompletionSink[];
+
+  constructor(sinks: readonly ModelInvocationSuccessfulCompletionSink[]) {
+    if (
+      !Array.isArray(sinks) ||
+      sinks.length < 2 ||
+      sinks.length > MAX_MODEL_INVOCATION_SUCCESSFUL_COMPLETION_SINKS ||
+      new Set(sinks).size !== sinks.length ||
+      sinks.some(
+        (sink) =>
+          !sink ||
+          typeof sink !== 'object' ||
+          typeof sink.record !== 'function',
+      )
+    ) {
+      throw new InvalidModelInvocationSuccessfulCompletionRouterError();
+    }
+    this.#sinks = Object.freeze([...sinks]);
+    Object.freeze(this);
+  }
+
+  supportsSuccessfulCompletionSink(
+    sink: ModelInvocationSuccessfulCompletionSink,
+  ): boolean {
+    return this.#sinks.some(
+      (candidate) =>
+        candidate === sink ||
+        candidate.supportsSuccessfulCompletionSink?.(sink) === true,
+    );
+  }
+
+  async record(
+    audit: Readonly<ModelInvocationAuditRecord>,
+    result: Readonly<GenerateResult>,
+  ): Promise<
+    Readonly<
+      | { handled: false }
+      | { handled: true; disposition: ModelInvocationAuditResult }
+    >
+  > {
+    for (const sink of this.#sinks) {
+      const routed = await sink.record(audit, result);
+      if (
+        !routed ||
+        typeof routed !== 'object' ||
+        Array.isArray(routed) ||
+        (routed.handled !== true && routed.handled !== false)
+      ) {
+        throw new InvalidModelInvocationSuccessfulCompletionRouterError();
+      }
+      if (routed.handled) return routed;
+      if (Object.keys(routed).length !== 1) {
+        throw new InvalidModelInvocationSuccessfulCompletionRouterError();
+      }
+    }
+    return Object.freeze({ handled: false as const });
+  }
+}
diff --git a/packages/ql3-ai/src/prompt/postgres-plugin-package-prompt-application/bootstrap.ts b/packages/ql3-ai/src/prompt/postgres-plugin-package-prompt-application/bootstrap.ts
index 46224adb..a765152c 100644
--- a/packages/ql3-ai/src/prompt/postgres-plugin-package-prompt-application/bootstrap.ts
+++ b/packages/ql3-ai/src/prompt/postgres-plugin-package-prompt-application/bootstrap.ts
@@ -15,6 +15,10 @@ import {
 import type { PluginPackagePromptOutputReadService } from '../../prompt-output/pluginPackagePromptOutputRead';
 import type { PluginPackagePromptExecutionOutputReadService } from '../../prompt-output/pluginPackagePromptExecutionOutputRead';
 import { bootstrapModelGatewayProfile } from '../../profile/profileComposition';
+import {
+  ModelInvocationSuccessfulCompletionRouter,
+  type ModelInvocationSuccessfulCompletionSink,
+} from '../../model-gateway/gateway';
 import {
   PostgresPluginPackagePromptApplicationUnavailableError,
   unavailable,
@@ -49,6 +53,8 @@ function assertEnabledOptions(
     (options.confirmActive !== undefined &&
       typeof options.confirmActive !== 'function') ||
     (options.now !== undefined && typeof options.now !== 'function') ||
+    (options.createAdditionalSuccessfulCompletion !== undefined &&
+      typeof options.createAdditionalSuccessfulCompletion !== 'function') ||
     (options.promptOutputKeys !== undefined &&
       (!options.promptOutputKeys ||
         typeof options.promptOutputKeys !== 'object' ||
@@ -118,17 +124,36 @@ export async function bootstrapPostgresPluginPackagePromptApplication(
         });
       },
       loadProviders: options.loadProviders,
-      ...(options.promptOutputKeys === undefined
+      ...(options.promptOutputKeys === undefined &&
+      options.createAdditionalSuccessfulCompletion === undefined
         ? {}
         : {
             createSuccessfulCompletion: (coordinator) => {
-              durableOutput =
-                new PluginPackagePromptOutputCompletionCoordinator({
+              const sinks: ModelInvocationSuccessfulCompletionSink[] = [];
+              if (options.promptOutputKeys !== undefined) {
+                durableOutput =
+                  new PluginPackagePromptOutputCompletionCoordinator({
                   coordinator,
                   keys: options.promptOutputKeys!,
                   ...(options.now === undefined ? {} : { now: options.now }),
                 });
-              return durableOutput;
+                sinks.push(durableOutput);
+              }
+              if (options.createAdditionalSuccessfulCompletion !== undefined) {
+                const additionalSuccessfulCompletion =
+                  options.createAdditionalSuccessfulCompletion(coordinator);
+                if (
+                  !additionalSuccessfulCompletion ||
+                  typeof additionalSuccessfulCompletion.record !== 'function'
+                ) {
+                  throw new TypeError(
+                    'PostgreSQL Package Prompt additional completion is invalid',
+                  );
+                }
+                sinks.push(additionalSuccessfulCompletion);
+              }
+              if (sinks.length === 1) return sinks[0]!;
+              return new ModelInvocationSuccessfulCompletionRouter(sinks);
             },
           }),
       audit: options.audit,
diff --git a/packages/ql3-ai/src/prompt/postgres-plugin-package-prompt-application/contracts.ts b/packages/ql3-ai/src/prompt/postgres-plugin-package-prompt-application/contracts.ts
index 47253b2e..38d3fadc 100644
--- a/packages/ql3-ai/src/prompt/postgres-plugin-package-prompt-application/contracts.ts
+++ b/packages/ql3-ai/src/prompt/postgres-plugin-package-prompt-application/contracts.ts
@@ -21,6 +21,8 @@ import type {
   ModelGatewayProfileAudit,
   ModelGatewayProviderAuthority,
 } from '../../profile/profileComposition';
+import type { DurableModelInvocationCoordinator } from '../../model-invocation/durableModelInvocationCoordinator';
+import type { ModelInvocationSuccessfulCompletionSink } from '../../model-gateway/gateway';
 import type { PluginPackagePromptCatalogCapability } from '../pluginPackagePromptCatalog';
 import type { PluginPackagePromptExecutionInspectionRepository } from '../pluginPackagePromptExecutionInspection';
 
@@ -80,6 +82,9 @@ export type BootstrapPostgresPluginPackagePromptApplicationOptions =
       maxConcurrent?: number;
       recoveryLimit?: number;
       now?: () => number;
+      createAdditionalSuccessfulCompletion?: (
+        coordinator: DurableModelInvocationCoordinator,
+      ) => ModelInvocationSuccessfulCompletionSink;
       promptOutputKeys?: PluginPackagePromptOutputArtifactKeyProvider;
       promptOutputRead?: Readonly<{
         authorizer: PluginPackagePromptOutputArtifactReadAuthorizer;
diff --git a/packages/ql3-ai/test/failure-diagnosis-application.test.cjs b/packages/ql3-ai/test/failure-diagnosis-application.test.cjs
new file mode 100644
index 00000000..04f30ac9
--- /dev/null
+++ b/packages/ql3-ai/test/failure-diagnosis-application.test.cjs
@@ -0,0 +1,271 @@
+const assert = require('node:assert/strict');
+const { test } = require('node:test');
+
+const {
+  CopilotFailureDiagnosisApplicationService,
+  CopilotFailureDiagnosisApplicationUnavailableError,
+} = require('@qinglong/ai/failure-diagnosis-application');
+const {
+  BUILTIN_RUN_LOG_EXCERPT_TOOL_DEFINITION,
+} = require('@qinglong/runtime-core/builtin-run-log-excerpt-tool');
+const {
+  createPluginPackageResourceGenerationFromReferences,
+} = require('@qinglong/runtime-core/plugin-package-resource-generation');
+const {
+  createProjectToolDefinitionSnapshot,
+} = require('@qinglong/runtime-core/project-tool-definition-snapshot');
+
+const NOW = 1_800_000_000_000;
+const KEY = Buffer.alloc(32, 0x42);
+const MODEL = Object.freeze({
+  provider: 'provider-primary',
+  model: 'model-diagnosis',
+  modelBoundary: 'external',
+  responseLanguage: 'zh-CN',
+  maxOutputTokens: 512,
+  egressPolicy: Object.freeze({
+    schema: 'qinglong/copilot-model-egress-policy@v1',
+    revision: 'application-test-v1',
+    potentiallySensitiveDataBoundaries: Object.freeze(['external']),
+    maxInputBytes: 64 * 1024,
+    maxOutputTokens: 1024,
+  }),
+});
+
+function snapshot() {
+  const generation = createPluginPackageResourceGenerationFromReferences({
+    installationId: 'installation-copilot-test',
+    projectId: 'project-1',
+    packageName: 'qinglong',
+    lockDigest: 'a'.repeat(64),
+    generation: 1,
+    previousActiveLockDigest: null,
+    contentDigest: 'b'.repeat(64),
+    resources: [],
+  });
+  return createProjectToolDefinitionSnapshot({
+    projectId: 'project-1',
+    contributions: [
+      {
+        generation,
+        revisionDigest: 'c'.repeat(64),
+        definitions: [BUILTIN_RUN_LOG_EXCERPT_TOOL_DEFINITION],
+      },
+    ],
+  });
+}
+
+function command(overrides = {}) {
+  return {
+    requestId: 'diagnosis-request-1',
+    traceId: 'diagnosis-trace-1',
+    projectId: 'project-1',
+    sourceRunId: 'source-run-1',
+    principal: {
+      subject: { type: 'user', id: 'owner-1' },
+      authenticationId: 'auth-1',
+      authenticatedAtMs: NOW - 1000,
+      expiresAtMs: NOW + 60_000,
+      assurance: 'multi_factor',
+    },
+    ...overrides,
+  };
+}
+
+function fixture(options = {}) {
+  let plan = null;
+  let artifacts = null;
+  let failArtifactOnce = options.failArtifactOnce === true;
+  let activeKeyCopies = [];
+  let resolvedKeyCopies = [];
+  let toolCalls = 0;
+  let modelCalls = 0;
+  let releaseTool;
+  const toolGate = options.blockTool
+    ? new Promise((resolve) => { releaseTool = resolve; })
+    : Promise.resolve();
+  const admissions = {
+    async findByRequestId(requestId) {
+      return plan?.requestId === requestId
+        ? { requestId, planDigest: plan.planDigest }
+        : null;
+    },
+    async findPlanByRequestId(requestId) {
+      return plan?.requestId === requestId ? plan : null;
+    },
+    async admit(value) {
+      const status = plan ? 'existing' : 'created';
+      plan ??= value;
+      assert.equal(plan.planDigest, value.planDigest);
+      return {
+        status,
+        receipt: {
+          requestId: plan.requestId,
+          planDigest: plan.planDigest,
+          runId: plan.runId,
+        },
+      };
+    },
+  };
+  const snapshots = {
+    async findCurrent() { return { snapshot: snapshot(), committedAtMs: NOW }; },
+  };
+  const runs = {
+    async findRunById() {
+      return {
+        id: 'source-run-1', projectId: 'project-1', status: 'failed',
+        version: 8, eventSequence: 8,
+      };
+    },
+    async findLatestAttemptByRunId() {
+      return {
+        id: 'source-attempt-1', runId: 'source-run-1', attempt: 1,
+        status: 'failed', executorType: 'remote_worker', callbackSequence: 0,
+        createdAtMs: NOW - 3000, finishedAtMs: NOW - 1000,
+        logArtifactId: `wlog-${'d'.repeat(30)}`,
+      };
+    },
+  };
+  const artifactRepository = {
+    async put(input, preview) {
+      if (failArtifactOnce) {
+        failArtifactOnce = false;
+        throw new Error('simulated admission-to-artifact crash');
+      }
+      if (artifacts) {
+        assert.deepEqual(input, artifacts.input);
+        assert.deepEqual(preview, artifacts.preview);
+        return { status: 'existing' };
+      }
+      artifacts = { input, preview };
+      return { status: 'inserted' };
+    },
+    async findInput() { return artifacts?.input ?? null; },
+    async findPreview() { return artifacts?.preview ?? null; },
+  };
+  const invocationKeys = {
+    async active() {
+      const copy = Buffer.from(KEY);
+      activeKeyCopies.push(copy);
+      return { keyId: 'invocation-key-1', key: copy };
+    },
+    async resolve(keyId) {
+      assert.equal(keyId, 'invocation-key-1');
+      const copy = Buffer.from(KEY);
+      resolvedKeyCopies.push(copy);
+      return { keyId, key: copy };
+    },
+  };
+  const unlocks = { async findByRequestId() { return null; }, async commit() {} };
+  const tool = {
+    admissions,
+    snapshots,
+    runs,
+    artifacts: artifactRepository,
+    invocationKeys,
+    resultKeys: { async resolve() { return null; } },
+    stepRuns: { async findById() { return null; } },
+    barriers: {}, completions: {}, failureCompletions: {},
+    resultKeyCatalog: {}, resultRekeys: {}, logs: {}, unlocks,
+  };
+  const model = {
+    admissions,
+    unlocks,
+    toolResults: {}, modelInvocations: {}, outputs: {}, gateway: {},
+    successfulCompletion: {}, finalizations: {},
+  };
+  const service = new CopilotFailureDiagnosisApplicationService({
+    admissions,
+    snapshots,
+    runs,
+    artifacts: artifactRepository,
+    invocationKeys,
+    authorizer: {
+      async authorize() {
+        return {
+          effect: 'allow', reasons: ['role_grant'],
+          fence: { projectVersion: 1, bindingVersion: 1 },
+        };
+      },
+    },
+    tool,
+    model,
+    modelIntent: MODEL,
+    executionTimeoutMs: 60_000,
+    now: () => NOW,
+    async executeTool() {
+      toolCalls += 1;
+      await toolGate;
+      return options.toolFailure
+        ? { outcome: 'failed', completionStatus: 'created', unlockStatus: null }
+        : {
+            outcome: 'succeeded', completionStatus: 'created',
+            unlockStatus: 'created', completion: {}, unlock: {},
+          };
+    },
+    async executeModel() {
+      modelCalls += 1;
+      return {
+        outcome: 'succeeded',
+        output: { artifactId: 'output-1' },
+        finalization: { requestId: 'diagnosis-request-1' },
+      };
+    },
+  });
+  return {
+    service,
+    releaseTool: () => releaseTool?.(),
+    state: () => ({
+      plan, artifacts, toolCalls, modelCalls,
+      activeKeyCopies, resolvedKeyCopies,
+    }),
+  };
+}
+
+test('application derives, admits and executes one server-owned diagnosis with exact replay', async () => {
+  const testFixture = fixture();
+  const first = await testFixture.service.execute(command());
+  assert.equal(first.admissionStatus, 'created');
+  assert.equal(first.tool.outcome, 'succeeded');
+  assert.equal(first.model.outcome, 'succeeded');
+  assert.equal(first.terminalizationRequired, false);
+  const second = await testFixture.service.execute(command());
+  assert.equal(second.admissionStatus, 'existing');
+  const state = testFixture.state();
+  assert.equal(state.toolCalls, 2);
+  assert.equal(state.modelCalls, 2);
+  assert.equal(state.plan.source.attemptId, 'source-attempt-1');
+  assert.equal(state.plan.tool.invocationArtifact.artifactId.startsWith('cdia:'), true);
+  assert.equal(state.activeKeyCopies[0].every((value) => value === 0), true);
+  assert.equal(state.resolvedKeyCopies[0].every((value) => value === 0), true);
+});
+
+test('application repairs the durable admission-to-Artifact crash window', async () => {
+  const testFixture = fixture({ failArtifactOnce: true });
+  await assert.rejects(
+    testFixture.service.execute(command()),
+    CopilotFailureDiagnosisApplicationUnavailableError,
+  );
+  assert.ok(testFixture.state().plan);
+  assert.equal(testFixture.state().artifacts, null);
+  const replay = await testFixture.service.execute(command());
+  assert.equal(replay.admissionStatus, 'existing');
+  assert.ok(testFixture.state().artifacts);
+});
+
+test('application coalesces exact callers and exposes Tool terminalization debt', async () => {
+  const concurrent = fixture({ blockTool: true });
+  const first = concurrent.service.execute(command());
+  const second = concurrent.service.execute(command());
+  assert.equal(first, second);
+  concurrent.releaseTool();
+  await first;
+  assert.equal(concurrent.state().toolCalls, 1);
+
+  const failed = fixture({ toolFailure: true });
+  const result = await failed.service.execute(command());
+  assert.equal(result.tool.outcome, 'failed');
+  assert.equal(result.model, null);
+  assert.equal(result.terminalizationRequired, true);
+  assert.equal(failed.state().modelCalls, 0);
+});
diff --git a/packages/ql3-ai/test/model-successful-completion-router.test.cjs b/packages/ql3-ai/test/model-successful-completion-router.test.cjs
new file mode 100644
index 00000000..b48ea2c2
--- /dev/null
+++ b/packages/ql3-ai/test/model-successful-completion-router.test.cjs
@@ -0,0 +1,81 @@
+const assert = require('node:assert/strict');
+const { test } = require('node:test');
+
+const {
+  BoundedModelGateway,
+  InvalidModelInvocationSuccessfulCompletionRouterError,
+  ModelInvocationSuccessfulCompletionRouter,
+} = require('@qinglong/ai/gateway');
+
+function sink(name, handled = false) {
+  return {
+    async record(audit) {
+      audit.order.push(name);
+      return handled
+        ? { handled: true, disposition: { status: 'created' } }
+        : { handled: false };
+    },
+  };
+}
+
+test('successful completion router exposes exact children and stops at the owning sink', async () => {
+  const first = sink('prompt');
+  const second = sink('copilot', true);
+  const third = sink('unreachable', true);
+  const nested = new ModelInvocationSuccessfulCompletionRouter([
+    second,
+    third,
+  ]);
+  const router = new ModelInvocationSuccessfulCompletionRouter([first, nested]);
+  const order = [];
+  assert.equal(router.supportsSuccessfulCompletionSink(first), true);
+  assert.equal(router.supportsSuccessfulCompletionSink(second), true);
+  assert.equal(router.supportsSuccessfulCompletionSink({ record() {} }), false);
+  assert.deepEqual(await router.record({ order }, {}), {
+    handled: true,
+    disposition: { status: 'created' },
+  });
+  assert.deepEqual(order, ['prompt', 'copilot']);
+
+  const gateway = new BoundedModelGateway({
+    providers: [
+      {
+        type: 'test',
+        async generate() { throw new Error('unused'); },
+        async *stream() { throw new Error('unused'); },
+        async listModels() { return []; },
+      },
+    ],
+    policies: { async resolve() { throw new Error('unused'); } },
+    pricing: { async resolve() { return null; } },
+    audit: { async record() {} },
+    successfulCompletion: router,
+    maxConcurrent: 1,
+  });
+  assert.equal(gateway.supportsSuccessfulCompletionSink(router), true);
+  assert.equal(gateway.supportsSuccessfulCompletionSink(second), true);
+});
+
+test('successful completion router rejects unbounded, duplicate and malformed sinks', async () => {
+  const valid = sink('valid');
+  assert.throws(
+    () => new ModelInvocationSuccessfulCompletionRouter([valid]),
+    InvalidModelInvocationSuccessfulCompletionRouterError,
+  );
+  assert.throws(
+    () => new ModelInvocationSuccessfulCompletionRouter([valid, valid]),
+    InvalidModelInvocationSuccessfulCompletionRouterError,
+  );
+  assert.throws(
+    () => new ModelInvocationSuccessfulCompletionRouter([valid, {}]),
+    InvalidModelInvocationSuccessfulCompletionRouterError,
+  );
+  const malformed = new ModelInvocationSuccessfulCompletionRouter([
+    valid,
+    { async record() { return { handled: false, widened: true }; } },
+  ]);
+  await assert.rejects(
+    malformed.record({ order: [] }, {}),
+    InvalidModelInvocationSuccessfulCompletionRouterError,
+  );
+});
diff --git a/packages/ql3-cluster-control/package.json b/packages/ql3-cluster-control/package.json
index 690b9375..275ddc72 100644
--- a/packages/ql3-cluster-control/package.json
+++ b/packages/ql3-cluster-control/package.json
@@ -35,6 +35,11 @@
       "require": "./dist/application-runtime/aiProductionApplication.js",
       "default": "./dist/application-runtime/aiProductionApplication.js"
     },
+    "./copilot-production": {
+      "types": "./dist/application-runtime/copilot/failureDiagnosisComposition.d.ts",
+      "require": "./dist/application-runtime/copilot/failureDiagnosisComposition.js",
+      "default": "./dist/application-runtime/copilot/failureDiagnosisComposition.js"
+    },
     "./failure-diagnosis-output-keyring": {
       "types": "./dist/copilot/failure-diagnosis/outputProjectedKeyring.d.ts",
       "require": "./dist/copilot/failure-diagnosis/outputProjectedKeyring.js",
diff --git a/packages/ql3-cluster-control/src/application-runtime/aiProductionApplication.ts b/packages/ql3-cluster-control/src/application-runtime/aiProductionApplication.ts
index c7362e76..2dd72370 100644
--- a/packages/ql3-cluster-control/src/application-runtime/aiProductionApplication.ts
+++ b/packages/ql3-cluster-control/src/application-runtime/aiProductionApplication.ts
@@ -1,4 +1,7 @@
 import type { ModelGatewayProfileAudit } from '@qinglong/ai/profile';
+import type { DurableModelInvocationCoordinator } from '@qinglong/ai/durable-model-invocation';
+import { CopilotFailureDiagnosisModelCompletionCoordinator } from '@qinglong/ai/failure-diagnosis-model-execution';
+import type { CopilotFailureDiagnosisApplicationService } from '@qinglong/ai/failure-diagnosis-application';
 import { BoundModelProviderCredentialProvider } from '@qinglong/ai/provider-credential';
 import { PostgresModelProviderCredentialReader } from '@qinglong/ai/postgres-model-provider-credential-storage';
 import { loadProjectedModelGatewayProviderAuthority } from '@qinglong/ai/projected-model-gateway-authority';
@@ -22,12 +25,19 @@ import {
   startProductionClusterControlApplication,
   type ProductionClusterControlApplicationOptions,
 } from './productionApplication';
+import {
+  createProductionClusterCopilotFailureDiagnosis,
+  prepareProductionClusterCopilotFailureDiagnosisProjection,
+  type ClusterCopilotFailureDiagnosisProjection,
+  type CreateProductionClusterCopilotFailureDiagnosisOptions,
+} from './copilot/failureDiagnosisComposition';
 
 export interface EnabledProductionClusterAiConfig {
   readonly enabled: true;
   readonly providerAuthorityFile: string;
   readonly secretRootDirectory: string;
   readonly promptOutputKeyringRootDirectory?: string;
+  readonly copilot?: Readonly<ClusterCopilotFailureDiagnosisProjection>;
   readonly maxConcurrent: number;
   readonly recoveryLimit: number;
   readonly databaseMaxConnections: number;
@@ -41,8 +51,18 @@ export interface ProductionClusterAiControlApplicationOptions {
   ) => void | Promise<void>;
   readonly startControl?: typeof startProductionClusterControlApplication;
   readonly bootstrapPrompt?: typeof bootstrapPostgresPluginPackagePromptApplication;
+  readonly createCopilot?: (
+    options: CreateProductionClusterCopilotFailureDiagnosisOptions,
+  ) => Promise<Readonly<CopilotFailureDiagnosisApplicationService>>;
+  readonly openAiDatabase?: ReturnType<typeof createPostgresDatabaseOpener>;
 }
 
+export type ProductionClusterAiControlApplicationResult = Extract<
+  ClusterControlApplicationResult,
+  { readonly status: 'active' }
+> &
+  Readonly<{ copilot?: Readonly<CopilotFailureDiagnosisApplicationService> }>;
+
 export class ProductionClusterAiConfigError extends TypeError {
   readonly code = 'QL3_CLUSTER_AI_CONFIG_INVALID';
 
@@ -121,6 +141,11 @@ export function loadProductionClusterAiConfig(
     'QL3_CLUSTER_AI_PROMPT_OUTPUT_ENABLED',
     false,
   );
+  const copilotEnabled = booleanValue(
+    environment,
+    'QL3_CLUSTER_AI_COPILOT_ENABLED',
+    false,
+  );
   return Object.freeze({
     enabled: true,
     providerAuthorityFile: requiredPath(
@@ -139,6 +164,28 @@ export function loadProductionClusterAiConfig(
           ),
         }
       : {}),
+    ...(copilotEnabled
+      ? {
+          copilot: Object.freeze({
+            configFile: requiredPath(
+              environment,
+              'QL3_CLUSTER_AI_COPILOT_CONFIG_FILE',
+            ),
+            invocationKeyringRootDirectory: requiredPath(
+              environment,
+              'QL3_CLUSTER_AI_COPILOT_INVOCATION_KEYRING_ROOT',
+            ),
+            resultKeyringRootDirectory: requiredPath(
+              environment,
+              'QL3_CLUSTER_AI_COPILOT_RESULT_KEYRING_ROOT',
+            ),
+            outputKeyringRootDirectory: requiredPath(
+              environment,
+              'QL3_CLUSTER_AI_COPILOT_OUTPUT_KEYRING_ROOT',
+            ),
+          }),
+        }
+      : {}),
     maxConcurrent: boundedInteger(
       environment,
       'QL3_CLUSTER_AI_MAX_CONCURRENT',
@@ -187,7 +234,7 @@ function aiDatabaseOpener(
  */
 export async function startProductionClusterAiControlApplication(
   options: ProductionClusterAiControlApplicationOptions,
-): Promise<ClusterControlApplicationResult> {
+): Promise<ProductionClusterAiControlApplicationResult> {
   if (
     !options ||
     typeof options !== 'object' ||
@@ -200,9 +247,26 @@ export async function startProductionClusterAiControlApplication(
     options.startControl ?? startProductionClusterControlApplication;
   const bootstrapPrompt =
     options.bootstrapPrompt ?? bootstrapPostgresPluginPackagePromptApplication;
-  if (typeof startControl !== 'function' || typeof bootstrapPrompt !== 'function') {
+  const createCopilot =
+    options.createCopilot ?? createProductionClusterCopilotFailureDiagnosis;
+  if (
+    typeof startControl !== 'function' ||
+    typeof bootstrapPrompt !== 'function' ||
+    typeof createCopilot !== 'function' ||
+    (options.openAiDatabase !== undefined &&
+      typeof options.openAiDatabase !== 'function')
+  ) {
     throw new TypeError('Production Cluster AI application factories are invalid');
   }
+  const copilotArtifactStore = options.control.workerIngress?.artifactStore;
+  if (
+    options.ai.copilot !== undefined &&
+    typeof copilotArtifactStore?.readLogRange !== 'function'
+  ) {
+    throw new TypeError(
+      'Cluster Copilot requires the bounded Worker log Artifact read capability',
+    );
+  }
   const secretMaterial =
     await createProjectedModelProviderSecretMaterialProvider({
       rootDirectory: options.ai.secretRootDirectory,
@@ -213,6 +277,12 @@ export async function startProductionClusterAiControlApplication(
       : await createPluginPackagePromptOutputProjectedKeyring({
           rootDirectory: options.ai.promptOutputKeyringRootDirectory,
         });
+  const preparedCopilot =
+    options.ai.copilot === undefined
+      ? undefined
+      : await prepareProductionClusterCopilotFailureDiagnosisProjection(
+          options.ai.copilot,
+        );
   let aiDatabase:
     | Awaited<ReturnType<ReturnType<typeof createPostgresDatabaseOpener>>>
     | undefined;
@@ -230,6 +300,12 @@ export async function startProductionClusterAiControlApplication(
     | BootstrapPostgresPluginPackagePromptApplicationResult
     | undefined;
   let controlApplication: ClusterControlApplicationResult | undefined;
+  let copilotApplication:
+    | Readonly<CopilotFailureDiagnosisApplicationService>
+    | undefined;
+  let copilotSuccessfulCompletion:
+    | CopilotFailureDiagnosisModelCompletionCoordinator
+    | undefined;
   let stopPromise: Promise<ClusterControlStopResult> | undefined;
   let promptOutputPolicy: ProjectPolicyEngine | undefined;
   const promptOutputReadAuthorizer = Object.freeze({
@@ -271,11 +347,9 @@ export async function startProductionClusterAiControlApplication(
     return stopPromise;
   };
   try {
-    const openDatabase = aiDatabaseOpener(
-      options.control.config,
-      options.ai,
-      onAiUnavailable,
-    );
+    const openDatabase =
+      options.openAiDatabase ??
+      aiDatabaseOpener(options.control.config, options.ai, onAiUnavailable);
     promptApplication = await bootstrapPrompt({
       enabled: true,
       async openDatabase() {
@@ -311,10 +385,41 @@ export async function startProductionClusterAiControlApplication(
             promptOutputKeys,
             promptOutputRead: { authorizer: promptOutputReadAuthorizer },
           }),
+      ...(preparedCopilot === undefined
+        ? {}
+        : {
+            createAdditionalSuccessfulCompletion(
+              coordinator: DurableModelInvocationCoordinator,
+            ) {
+              if (copilotSuccessfulCompletion) {
+                throw new Error(
+                  'Cluster Copilot completion was created more than once',
+                );
+              }
+              copilotSuccessfulCompletion =
+                new CopilotFailureDiagnosisModelCompletionCoordinator({
+                  coordinator,
+                  keys: preparedCopilot.outputKeys,
+                });
+              return copilotSuccessfulCompletion;
+            },
+          }),
     });
     if (promptApplication.status !== 'active') {
       throw new Error('Cluster AI Prompt application did not activate');
     }
+    if (preparedCopilot !== undefined) {
+      if (!copilotSuccessfulCompletion || !aiDatabase || !copilotArtifactStore) {
+        throw new Error('Cluster Copilot shared authorities did not activate');
+      }
+      copilotApplication = await createCopilot({
+        pool: aiDatabase.pool,
+        gateway: promptApplication.capability,
+        prepared: preparedCopilot,
+        successfulCompletion: copilotSuccessfulCompletion,
+        artifactStore: copilotArtifactStore,
+      });
+    }
     controlApplication = await startControl({
       ...options.control,
       promptCatalog: {
@@ -356,6 +461,9 @@ export async function startProductionClusterAiControlApplication(
           ? 'unavailable'
           : activeControl.availabilityStatus();
       },
+      ...(copilotApplication === undefined
+        ? {}
+        : { copilot: copilotApplication }),
       stop,
     });
   } catch (error) {
diff --git a/packages/ql3-cluster-control/src/application-runtime/copilot/failureDiagnosisComposition.ts b/packages/ql3-cluster-control/src/application-runtime/copilot/failureDiagnosisComposition.ts
new file mode 100644
index 00000000..1b0d55f3
--- /dev/null
+++ b/packages/ql3-cluster-control/src/application-runtime/copilot/failureDiagnosisComposition.ts
@@ -0,0 +1,466 @@
+import { Buffer } from 'node:buffer';
+import { basename, dirname } from 'node:path';
+
+import {
+  CopilotFailureDiagnosisApplicationService,
+  type CopilotFailureDiagnosisApplicationDependencies,
+} from '@qinglong/ai/failure-diagnosis-application';
+import type { PrepareCopilotFailureDiagnosisModelIntent } from '@qinglong/ai/failure-diagnosis-execution-admission';
+import {
+  CopilotFailureDiagnosisModelCompletionCoordinator,
+  executeCopilotFailureDiagnosisModel,
+  type CopilotFailureDiagnosisToolResultReader,
+} from '@qinglong/ai/failure-diagnosis-model-execution';
+import {
+  executeCopilotFailureDiagnosisTool,
+  restoreCopilotFailureDiagnosisTrustedToolAuthority,
+} from '@qinglong/ai/failure-diagnosis-tool-execution';
+import { PostgresCopilotFailureDiagnosisAdmissionRepository } from '@qinglong/ai/postgres-failure-diagnosis-admission-storage';
+import { PostgresCopilotFailureDiagnosisModelRepository } from '@qinglong/ai/postgres-failure-diagnosis-model-execution-storage';
+import { PostgresCopilotFailureDiagnosisToolUnlockRepository } from '@qinglong/ai/postgres-failure-diagnosis-tool-execution-storage';
+import type { ActiveModelGatewayCapability } from '@qinglong/ai/profile';
+import {
+  PostgresProjectPolicyRepository,
+  PostgresProjectToolDefinitionSnapshotRepository,
+  PostgresRunAttemptLogRetentionClaimRepository,
+  PostgresRunRepository,
+  PostgresStepRunRepository,
+  PostgresToolExecutionCompletionRepository,
+  PostgresToolExecutionFailureCompletionRepository,
+  PostgresToolExecutionStartBarrierRepository,
+  PostgresToolInvocationArtifactRepository,
+  PostgresToolResultKeyCatalogReader,
+  PostgresToolResultRekeyReader,
+  type QingLongPostgresPool,
+} from '@qinglong/cluster-postgres/runtime';
+import {
+  BuiltInRunLogExcerptToolAdapter,
+} from '@qinglong/runtime-core/builtin-run-log-excerpt-tool';
+import type { RunAttemptLogReadPort } from '@qinglong/runtime-core/builtin-run-log-excerpt-projection';
+import { ProjectPolicyEngine } from '@qinglong/runtime-core/project-policy';
+import { RunAttemptLogReadService } from '@qinglong/runtime-core/run-attempt-log-read';
+import { openTrustedToolSuccessCompletion } from '@qinglong/runtime-core/trusted-tool-completion';
+import { TrustedToolExecutionAdapterRegistry } from '@qinglong/runtime-core/trusted-tool-execution';
+
+import type { ClusterRemoteWorkerArtifactStore } from '../../remote-execution/remoteWorkerCompletionService';
+import { PrivateProjectedFileReader } from '../../security/privateProjectedFile';
+import { createClusterToolInvocationProjectedKeyring } from '../../trusted-tool/key-management/toolInvocationProjectedKeyring';
+import { createClusterToolResultProjectedKeyring } from '../../trusted-tool/key-management/toolResultProjectedKeyring';
+import { createClusterCopilotFailureDiagnosisOutputProjectedKeyring } from '../../copilot/failure-diagnosis/outputProjectedKeyring';
+
+export const CLUSTER_COPILOT_FAILURE_DIAGNOSIS_CONFIG_SCHEMA =
+  'qinglong/cluster-copilot-failure-diagnosis-config@v1' as const;
+export const MAX_CLUSTER_COPILOT_FAILURE_DIAGNOSIS_CONFIG_BYTES = 16 * 1024;
+
+const IDENTITY = /^[A-Za-z0-9][A-Za-z0-9._:-]{0,127}$/;
+const MODEL_BOUNDARIES = ['on_device', 'external'] as const;
+const RESPONSE_LANGUAGES = ['en', 'zh-CN'] as const;
+const EGRESS_SCHEMA = 'qinglong/copilot-model-egress-policy@v1' as const;
+
+export interface ClusterCopilotFailureDiagnosisConfig {
+  readonly schema: typeof CLUSTER_COPILOT_FAILURE_DIAGNOSIS_CONFIG_SCHEMA;
+  readonly provider: string;
+  readonly model: string;
+  readonly modelBoundary: 'on_device' | 'external';
+  readonly responseLanguage: 'en' | 'zh-CN';
+  readonly maxOutputTokens: number;
+  readonly executionTimeoutMs: number;
+  readonly egressPolicy: PrepareCopilotFailureDiagnosisModelIntent['egressPolicy'];
+}
+
+export interface ClusterCopilotFailureDiagnosisProjection {
+  readonly configFile: string;
+  readonly invocationKeyringRootDirectory: string;
+  readonly resultKeyringRootDirectory: string;
+  readonly outputKeyringRootDirectory: string;
+}
+
+export interface CreateProductionClusterCopilotFailureDiagnosisOptions {
+  readonly pool: QingLongPostgresPool;
+  readonly gateway: ActiveModelGatewayCapability;
+  readonly prepared: PreparedClusterCopilotFailureDiagnosisProjection;
+  readonly successfulCompletion: CopilotFailureDiagnosisModelCompletionCoordinator;
+  readonly artifactStore: ClusterRemoteWorkerArtifactStore;
+}
+
+export interface PreparedClusterCopilotFailureDiagnosisProjection {
+  readonly config: Readonly<ClusterCopilotFailureDiagnosisConfig>;
+  readonly invocationKeys: Awaited<
+    ReturnType<typeof createClusterToolInvocationProjectedKeyring>
+  >;
+  readonly resultKeys: Awaited<
+    ReturnType<typeof createClusterToolResultProjectedKeyring>
+  >;
+  readonly outputKeys: Awaited<
+    ReturnType<typeof createClusterCopilotFailureDiagnosisOutputProjectedKeyring>
+  >;
+}
+
+export class ClusterCopilotFailureDiagnosisCompositionError extends Error {
+  readonly code = 'QL3_CLUSTER_COPILOT_FAILURE_DIAGNOSIS_COMPOSITION_INVALID';
+
+  constructor(message: string, options?: ErrorOptions) {
+    super(`Cluster Copilot failure diagnosis composition is invalid: ${message}`, options);
+    this.name = 'ClusterCopilotFailureDiagnosisCompositionError';
+  }
+}
+
+function invalid(message: string, cause?: unknown): never {
+  throw new ClusterCopilotFailureDiagnosisCompositionError(message, {
+    cause: cause instanceof Error ? cause : undefined,
+  });
+}
+
+function record(value: unknown, label: string): Record<string, unknown> {
+  if (!value || typeof value !== 'object' || Array.isArray(value)) {
+    return invalid(`${label} must be an object`);
+  }
+  return value as Record<string, unknown>;
+}
+
+function exactKeys(
+  value: Readonly<Record<string, unknown>>,
+  expected: readonly string[],
+  label: string,
+): void {
+  const actual = Object.keys(value).sort();
+  const canonical = [...expected].sort();
+  if (
+    actual.length !== canonical.length ||
+    actual.some((key, index) => key !== canonical[index])
+  ) {
+    return invalid(`${label} shape is invalid`);
+  }
+}
+
+function identity(value: unknown, label: string): string {
+  if (typeof value !== 'string' || !IDENTITY.test(value)) {
+    return invalid(`${label} is invalid`);
+  }
+  return value;
+}
+
+function integer(
+  value: unknown,
+  minimum: number,
+  maximum: number,
+  label: string,
+): number {
+  if (
+    typeof value !== 'number' ||
+    !Number.isSafeInteger(value) ||
+    value < minimum ||
+    value > maximum
+  ) {
+    return invalid(`${label} is invalid`);
+  }
+  return value;
+}
+
+export function normalizeClusterCopilotFailureDiagnosisConfig(
+  value: unknown,
+): Readonly<ClusterCopilotFailureDiagnosisConfig> {
+  const candidate = record(value, 'configuration');
+  exactKeys(
+    candidate,
+    [
+      'egressPolicy',
+      'executionTimeoutMs',
+      'maxOutputTokens',
+      'model',
+      'modelBoundary',
+      'provider',
+      'responseLanguage',
+      'schema',
+    ],
+    'configuration',
+  );
+  if (candidate.schema !== CLUSTER_COPILOT_FAILURE_DIAGNOSIS_CONFIG_SCHEMA) {
+    return invalid('schema is invalid');
+  }
+  if (!MODEL_BOUNDARIES.includes(candidate.modelBoundary as never)) {
+    return invalid('model boundary is invalid');
+  }
+  if (!RESPONSE_LANGUAGES.includes(candidate.responseLanguage as never)) {
+    return invalid('response language is invalid');
+  }
+  const egress = record(candidate.egressPolicy, 'egress policy');
+  exactKeys(
+    egress,
+    [
+      'maxInputBytes',
+      'maxOutputTokens',
+      'potentiallySensitiveDataBoundaries',
+      'revision',
+      'schema',
+    ],
+    'egress policy',
+  );
+  if (egress.schema !== EGRESS_SCHEMA) return invalid('egress schema is invalid');
+  const selected = egress.potentiallySensitiveDataBoundaries;
+  if (
+    !Array.isArray(selected) ||
+    selected.length < 1 ||
+    selected.length > MODEL_BOUNDARIES.length ||
+    selected.some((entry) => !MODEL_BOUNDARIES.includes(entry as never)) ||
+    new Set(selected).size !== selected.length ||
+    MODEL_BOUNDARIES.filter((entry) => selected.includes(entry)).some(
+      (entry, index) => entry !== selected[index],
+    ) ||
+    !selected.includes(candidate.modelBoundary)
+  ) {
+    return invalid('egress model boundaries are invalid');
+  }
+  const egressMaxOutputTokens = integer(
+    egress.maxOutputTokens,
+    1,
+    4_096,
+    'egress max output tokens',
+  );
+  const maxOutputTokens = integer(
+    candidate.maxOutputTokens,
+    1,
+    egressMaxOutputTokens,
+    'max output tokens',
+  );
+  return Object.freeze({
+    schema: CLUSTER_COPILOT_FAILURE_DIAGNOSIS_CONFIG_SCHEMA,
+    provider: identity(candidate.provider, 'provider'),
+    model: identity(candidate.model, 'model'),
+    modelBoundary: candidate.modelBoundary as 'on_device' | 'external',
+    responseLanguage: candidate.responseLanguage as 'en' | 'zh-CN',
+    maxOutputTokens,
+    executionTimeoutMs: integer(
+      candidate.executionTimeoutMs,
+      1,
+      5 * 60_000,
+      'execution timeout',
+    ),
+    egressPolicy: Object.freeze({
+      schema: EGRESS_SCHEMA,
+      revision: identity(egress.revision, 'egress revision'),
+      potentiallySensitiveDataBoundaries: Object.freeze([...selected]) as (
+        | 'on_device'
+        | 'external'
+      )[],
+      maxInputBytes: integer(
+        egress.maxInputBytes,
+        1,
+        64 * 1024,
+        'egress max input bytes',
+      ),
+      maxOutputTokens: egressMaxOutputTokens,
+    }),
+  });
+}
+
+export function canonicalClusterCopilotFailureDiagnosisConfig(
+  value: unknown,
+): Buffer {
+  return Buffer.from(
+    `${JSON.stringify(normalizeClusterCopilotFailureDiagnosisConfig(value))}\n`,
+    'utf8',
+  );
+}
+
+export async function loadClusterCopilotFailureDiagnosisConfig(
+  configFile: string,
+): Promise<Readonly<ClusterCopilotFailureDiagnosisConfig>> {
+  let bytes: Buffer | undefined;
+  let canonical: Buffer | undefined;
+  try {
+    const reader = new PrivateProjectedFileReader({
+      rootDirectory: dirname(configFile),
+      minimumBytes: 1,
+      maximumBytes: MAX_CLUSTER_COPILOT_FAILURE_DIAGNOSIS_CONFIG_BYTES,
+      access: 'read_only_keyring',
+    });
+    bytes = await reader.read(basename(configFile));
+    const parsed = JSON.parse(bytes.toString('utf8')) as unknown;
+    const config = normalizeClusterCopilotFailureDiagnosisConfig(parsed);
+    canonical = canonicalClusterCopilotFailureDiagnosisConfig(config);
+    if (!canonical.equals(bytes)) return invalid('file is not canonical');
+    return config;
+  } catch (cause) {
+    return cause instanceof ClusterCopilotFailureDiagnosisCompositionError
+      ? invalid(cause.message, cause)
+      : invalid('projected configuration is unavailable', cause);
+  } finally {
+    bytes?.fill(0);
+    canonical?.fill(0);
+  }
+}
+
+function modelIntent(
+  config: Readonly<ClusterCopilotFailureDiagnosisConfig>,
+): Readonly<PrepareCopilotFailureDiagnosisModelIntent> {
+  return Object.freeze({
+    provider: config.provider,
+    model: config.model,
+    modelBoundary: config.modelBoundary,
+    responseLanguage: config.responseLanguage,
+    maxOutputTokens: config.maxOutputTokens,
+    egressPolicy: config.egressPolicy,
+  });
+}
+
+export async function prepareProductionClusterCopilotFailureDiagnosisProjection(
+  projection: ClusterCopilotFailureDiagnosisProjection,
+): Promise<Readonly<PreparedClusterCopilotFailureDiagnosisProjection>> {
+  if (!projection || typeof projection !== 'object' || Array.isArray(projection)) {
+    return invalid('projection is invalid');
+  }
+  const [config, invocationKeys, resultKeys, outputKeys] = await Promise.all([
+    loadClusterCopilotFailureDiagnosisConfig(projection.configFile),
+    createClusterToolInvocationProjectedKeyring({
+      rootDirectory: projection.invocationKeyringRootDirectory,
+    }),
+    createClusterToolResultProjectedKeyring({
+      rootDirectory: projection.resultKeyringRootDirectory,
+    }),
+    createClusterCopilotFailureDiagnosisOutputProjectedKeyring({
+      rootDirectory: projection.outputKeyringRootDirectory,
+    }),
+  ]);
+  return Object.freeze({ config, invocationKeys, resultKeys, outputKeys });
+}
+
+export async function createProductionClusterCopilotFailureDiagnosis(
+  options: CreateProductionClusterCopilotFailureDiagnosisOptions,
+): Promise<Readonly<CopilotFailureDiagnosisApplicationService>> {
+  if (
+    !options ||
+    typeof options !== 'object' ||
+    Array.isArray(options) ||
+    typeof options.pool?.query !== 'function' ||
+    typeof options.pool?.connect !== 'function' ||
+    typeof options.gateway?.generate !== 'function' ||
+    typeof options.gateway?.supportsSuccessfulCompletionSink !== 'function' ||
+    typeof options.successfulCompletion?.begin !== 'function' ||
+    typeof options.successfulCompletion?.record !== 'function' ||
+    !options.prepared ||
+    typeof options.artifactStore?.readLogRange !== 'function'
+  ) {
+    return invalid('dependencies are unavailable');
+  }
+  if (
+    !options.gateway.supportsSuccessfulCompletionSink(
+      options.successfulCompletion,
+    )
+  ) {
+    return invalid('shared Model completion authority is unavailable');
+  }
+  const { config, invocationKeys, resultKeys } = options.prepared;
+  const admissions = new PostgresCopilotFailureDiagnosisAdmissionRepository(
+    options.pool,
+  );
+  const snapshots = new PostgresProjectToolDefinitionSnapshotRepository(
+    options.pool,
+  );
+  const runs = new PostgresRunRepository(options.pool);
+  const artifacts = new PostgresToolInvocationArtifactRepository(options.pool);
+  const stepRuns = new PostgresStepRunRepository(options.pool);
+  const barriers = new PostgresToolExecutionStartBarrierRepository(options.pool);
+  const completions = new PostgresToolExecutionCompletionRepository(options.pool);
+  const failureCompletions =
+    new PostgresToolExecutionFailureCompletionRepository(options.pool);
+  const resultKeyCatalog = new PostgresToolResultKeyCatalogReader(options.pool);
+  const resultRekeys = new PostgresToolResultRekeyReader(options.pool);
+  const unlocks = new PostgresCopilotFailureDiagnosisToolUnlockRepository(
+    options.pool,
+  );
+  const models = new PostgresCopilotFailureDiagnosisModelRepository(options.pool);
+  const logReader = new RunAttemptLogReadService(
+    runs,
+    Object.freeze({
+      read: options.artifactStore.readLogRange.bind(options.artifactStore),
+    }),
+    {
+      executorType: 'remote_worker',
+      artifactIdPattern: /^wlog-[a-f0-9]{30}$/,
+      maximumReadBytes: 256 * 1024,
+      activeMissingIsPending: true,
+    },
+    new PostgresRunAttemptLogRetentionClaimRepository(options.pool),
+  );
+  const logs: RunAttemptLogReadPort = Object.freeze({
+    read: logReader.read.bind(logReader),
+  });
+  const successfulCompletion = options.successfulCompletion;
+  const toolResults: CopilotFailureDiagnosisToolResultReader = Object.freeze({
+    async open(requestId: string, startId: string) {
+      const plan = await admissions.findPlanByRequestId(requestId);
+      if (!plan) return invalid('diagnosis plan is unavailable');
+      const snapshot = await snapshots.findCurrent(plan.projectId);
+      if (!snapshot) return invalid('Tool snapshot is unavailable');
+      const authority = restoreCopilotFailureDiagnosisTrustedToolAuthority(
+        plan,
+        snapshot.snapshot,
+      );
+      const definitions = authority.bindings.definitionRegistry();
+      const adapters = new TrustedToolExecutionAdapterRegistry(
+        authority.bindings,
+        [
+          new BuiltInRunLogExcerptToolAdapter(
+            authority.binding,
+            'cluster-control',
+            definitions,
+            logs,
+          ),
+        ],
+      );
+      return openTrustedToolSuccessCompletion(startId, {
+        completions,
+        barriers,
+        resultKeyCatalog,
+        resultRekeys,
+        resultKeys,
+        adapters,
+      });
+    },
+  });
+  const policy = new ProjectPolicyEngine(
+    new PostgresProjectPolicyRepository(options.pool),
+  );
+  const tool = Object.freeze({
+    admissions,
+    snapshots,
+    artifacts,
+    invocationKeys,
+    resultKeys,
+    stepRuns,
+    runs,
+    barriers,
+    completions,
+    failureCompletions,
+    resultKeyCatalog,
+    resultRekeys,
+    logs,
+    unlocks,
+  });
+  const model = Object.freeze({
+    admissions,
+    unlocks,
+    toolResults,
+    modelInvocations: models,
+    outputs: models,
+    gateway: options.gateway,
+    successfulCompletion,
+    finalizations: models,
+  });
+  const dependencies: CopilotFailureDiagnosisApplicationDependencies = {
+    admissions,
+    snapshots,
+    runs,
+    artifacts,
+    invocationKeys,
+    authorizer: policy,
+    tool,
+    model,
+    executeTool: executeCopilotFailureDiagnosisTool,
+    executeModel: executeCopilotFailureDiagnosisModel,
+    modelIntent: modelIntent(config),
+    executionTimeoutMs: config.executionTimeoutMs,
+  };
+  return new CopilotFailureDiagnosisApplicationService(dependencies);
+}
diff --git a/packages/ql3-cluster-control/test/aiProductionApplication.test.cjs b/packages/ql3-cluster-control/test/aiProductionApplication.test.cjs
index 6f5b889b..9d1f0d8b 100644
--- a/packages/ql3-cluster-control/test/aiProductionApplication.test.cjs
+++ b/packages/ql3-cluster-control/test/aiProductionApplication.test.cjs
@@ -13,6 +13,18 @@ const {
   canonicalPluginPackagePromptOutputKeyringManifest,
   PLUGIN_PACKAGE_PROMPT_OUTPUT_KEYRING_MANIFEST_SCHEMA,
 } = require('@qinglong/ai/plugin-package-prompt-output-keyring-manifest');
+const {
+  canonicalClusterToolInvocationKeyringManifest,
+  CLUSTER_TOOL_INVOCATION_KEYRING_MANIFEST_SCHEMA,
+} = require('@qinglong/cluster-control/trusted-tool-invocation-keyring');
+const {
+  canonicalClusterToolResultKeyringManifest,
+  CLUSTER_TOOL_RESULT_KEYRING_MANIFEST_SCHEMA,
+} = require('@qinglong/cluster-control/trusted-tool-result-keyring');
+const {
+  canonicalClusterCopilotFailureDiagnosisOutputKeyringManifest,
+  CLUSTER_COPILOT_FAILURE_DIAGNOSIS_OUTPUT_KEYRING_MANIFEST_SCHEMA,
+} = require('@qinglong/cluster-control/failure-diagnosis-output-keyring');
 
 function enabledEnvironment(overrides = {}) {
   return {
@@ -74,6 +86,161 @@ test('AI config is fail-closed and bounded behind the explicit process flag', ()
       ),
     /QL3_CLUSTER_AI_PROMPT_OUTPUT_KEYRING_ROOT is invalid/,
   );
+  assert.throws(
+    () =>
+      loadProductionClusterAiConfig(
+        enabledEnvironment({ QL3_CLUSTER_AI_COPILOT_ENABLED: 'true' }),
+      ),
+    /QL3_CLUSTER_AI_COPILOT_CONFIG_FILE is invalid/,
+  );
+  assert.deepEqual(
+    loadProductionClusterAiConfig(
+      enabledEnvironment({
+        QL3_CLUSTER_AI_COPILOT_ENABLED: 'true',
+        QL3_CLUSTER_AI_COPILOT_CONFIG_FILE: '/run/ql3/copilot/config.json',
+        QL3_CLUSTER_AI_COPILOT_INVOCATION_KEYRING_ROOT: '/run/ql3/invocation',
+        QL3_CLUSTER_AI_COPILOT_RESULT_KEYRING_ROOT: '/run/ql3/result',
+        QL3_CLUSTER_AI_COPILOT_OUTPUT_KEYRING_ROOT: '/run/ql3/output',
+      }),
+    ).copilot,
+    {
+      configFile: '/run/ql3/copilot/config.json',
+      invocationKeyringRootDirectory: '/run/ql3/invocation',
+      resultKeyringRootDirectory: '/run/ql3/result',
+      outputKeyringRootDirectory: '/run/ql3/output',
+    },
+  );
+});
+
+async function projectedFile(root, name, bytes) {
+  await writeFile(join(root, name), bytes, { mode: 0o440 });
+  await chmod(join(root, name), 0o440);
+}
+
+test('Copilot composition is explicit, shares the Prompt gateway and exposes no route', async () => {
+  const secretRoot = await mkdtemp(join(tmpdir(), 'ql3-cluster-ai-secret-'));
+  const configRoot = await mkdtemp(join(tmpdir(), 'ql3-copilot-config-'));
+  const invocationRoot = await mkdtemp(join(tmpdir(), 'ql3-copilot-invocation-'));
+  const resultRoot = await mkdtemp(join(tmpdir(), 'ql3-copilot-result-'));
+  const outputRoot = await mkdtemp(join(tmpdir(), 'ql3-copilot-output-'));
+  const key = Buffer.alloc(32, 0x55).toString('base64url');
+  const config = Buffer.from(`${JSON.stringify({
+    schema: 'qinglong/cluster-copilot-failure-diagnosis-config@v1',
+    provider: 'provider-primary',
+    model: 'model-diagnosis',
+    modelBoundary: 'external',
+    responseLanguage: 'zh-CN',
+    maxOutputTokens: 512,
+    executionTimeoutMs: 60_000,
+    egressPolicy: {
+      schema: 'qinglong/copilot-model-egress-policy@v1',
+      revision: 'cluster-copilot-v1',
+      potentiallySensitiveDataBoundaries: ['external'],
+      maxInputBytes: 64 * 1024,
+      maxOutputTokens: 1024,
+    },
+  })}\n`);
+  const invocation = canonicalClusterToolInvocationKeyringManifest({
+    schema: CLUSTER_TOOL_INVOCATION_KEYRING_MANIFEST_SCHEMA,
+    activeKeyId: 'invocation-key-1',
+    keys: { 'invocation-key-1': key },
+  });
+  const result = canonicalClusterToolResultKeyringManifest({
+    schema: CLUSTER_TOOL_RESULT_KEYRING_MANIFEST_SCHEMA,
+    keys: { 'result-key-1': key },
+  });
+  const output = canonicalClusterCopilotFailureDiagnosisOutputKeyringManifest({
+    schema: CLUSTER_COPILOT_FAILURE_DIAGNOSIS_OUTPUT_KEYRING_MANIFEST_SCHEMA,
+    activeKeyId: 'output-key-1',
+    keys: { 'output-key-1': key },
+  });
+  const gateway = {
+    generate() {},
+    supportsSuccessfulCompletionSink(sink) {
+      return sink === registeredSink;
+    },
+  };
+  const fakePool = { query() {}, connect() {} };
+  const artifactStore = { put() {}, inspect() {}, readLogRange() {} };
+  const copilot = Object.freeze({ execute() {} });
+  let registeredSink;
+  let created;
+  let controlOptions;
+  try {
+    await Promise.all([
+      projectedFile(configRoot, 'config.json', config),
+      projectedFile(invocationRoot, 'keyring.json', invocation),
+      projectedFile(resultRoot, 'keyring.json', result),
+      projectedFile(outputRoot, 'keyring.json', output),
+    ]);
+    const application = await startProductionClusterAiControlApplication({
+      control: {
+        config: controlConfig(),
+        workerIngress: {
+          config: { enabled: true },
+          artifactStore,
+        },
+      },
+      ai: {
+        enabled: true,
+        providerAuthorityFile: '/unused/providers.json',
+        secretRootDirectory: secretRoot,
+        copilot: {
+          configFile: join(configRoot, 'config.json'),
+          invocationKeyringRootDirectory: invocationRoot,
+          resultKeyringRootDirectory: resultRoot,
+          outputKeyringRootDirectory: outputRoot,
+        },
+        maxConcurrent: 1,
+        recoveryLimit: 1,
+        databaseMaxConnections: 1,
+      },
+      audit() {},
+      async openAiDatabase() {
+        return { pool: fakePool, async close() {} };
+      },
+      async bootstrapPrompt(options) {
+        await options.openDatabase();
+        registeredSink = options.createAdditionalSuccessfulCompletion({
+          async recordWithAtomicSuccess() {},
+        });
+        return {
+          status: 'active', profile: 'cluster', readiness: {}, capability: gateway,
+          prompts: {}, promptCatalog: {}, promptExecutions: {},
+          promptExecutionInspections: {}, async stop() { return 'stopped'; },
+        };
+      },
+      async createCopilot(options) {
+        created = options;
+        return copilot;
+      },
+      async startControl(options) {
+        controlOptions = options;
+        return {
+          status: 'active', address: { host: '127.0.0.1', port: 5800 },
+          evidence: {}, recovery: { safe: true, remaining: 0, failed: 0 },
+          unavailable: new Promise(() => {}), availabilityStatus() { return 'ready'; },
+          async stop() { return 'stopped'; },
+        };
+      },
+    });
+    assert.equal(application.copilot, copilot);
+    assert.equal(created.pool, fakePool);
+    assert.equal(created.gateway, gateway);
+    assert.equal(created.successfulCompletion, registeredSink);
+    assert.equal(created.artifactStore, artifactStore);
+    assert.equal('copilot' in controlOptions, false);
+    assert.equal(await application.stop(), 'stopped');
+  } finally {
+    config.fill(0); invocation.fill(0); result.fill(0); output.fill(0);
+    await Promise.all([
+      rm(secretRoot, { recursive: true, force: true }),
+      rm(configRoot, { recursive: true, force: true }),
+      rm(invocationRoot, { recursive: true, force: true }),
+      rm(resultRoot, { recursive: true, force: true }),
+      rm(outputRoot, { recursive: true, force: true }),
+    ]);
+  }
 });
 
 test('explicit AI composition injects one reviewed Prompt capability and drains it after HTTP control', async () => {
diff --git a/packages/ql3-cluster-control/test/copilotFailureDiagnosisComposition.test.cjs b/packages/ql3-cluster-control/test/copilotFailureDiagnosisComposition.test.cjs
new file mode 100644
index 00000000..652822cd
--- /dev/null
+++ b/packages/ql3-cluster-control/test/copilotFailureDiagnosisComposition.test.cjs
@@ -0,0 +1,92 @@
+const assert = require('node:assert/strict');
+const { chmod, mkdtemp, rm, writeFile } = require('node:fs/promises');
+const { tmpdir } = require('node:os');
+const { join } = require('node:path');
+const { test } = require('node:test');
+
+const {
+  CLUSTER_COPILOT_FAILURE_DIAGNOSIS_CONFIG_SCHEMA,
+  ClusterCopilotFailureDiagnosisCompositionError,
+  canonicalClusterCopilotFailureDiagnosisConfig,
+  loadClusterCopilotFailureDiagnosisConfig,
+  normalizeClusterCopilotFailureDiagnosisConfig,
+} = require('@qinglong/cluster-control/copilot-production');
+
+function config(overrides = {}) {
+  return {
+    schema: CLUSTER_COPILOT_FAILURE_DIAGNOSIS_CONFIG_SCHEMA,
+    provider: 'provider-primary',
+    model: 'model-diagnosis',
+    modelBoundary: 'external',
+    responseLanguage: 'zh-CN',
+    maxOutputTokens: 512,
+    executionTimeoutMs: 60_000,
+    egressPolicy: {
+      schema: 'qinglong/copilot-model-egress-policy@v1',
+      revision: 'cluster-copilot-v1',
+      potentiallySensitiveDataBoundaries: ['external'],
+      maxInputBytes: 64 * 1024,
+      maxOutputTokens: 1024,
+    },
+    ...overrides,
+  };
+}
+
+test('normalizes one bounded deployment-owned Copilot model intent', () => {
+  const normalized = normalizeClusterCopilotFailureDiagnosisConfig(config());
+  assert.equal(normalized.provider, 'provider-primary');
+  assert.equal(normalized.executionTimeoutMs, 60_000);
+  assert.equal(Object.isFrozen(normalized), true);
+  assert.equal(Object.isFrozen(normalized.egressPolicy), true);
+  assert.throws(
+    () => normalizeClusterCopilotFailureDiagnosisConfig(config({ extra: true })),
+    ClusterCopilotFailureDiagnosisCompositionError,
+  );
+  assert.throws(
+    () => normalizeClusterCopilotFailureDiagnosisConfig(config({
+      modelBoundary: 'on_device',
+    })),
+    /egress model boundaries/,
+  );
+  assert.throws(
+    () => normalizeClusterCopilotFailureDiagnosisConfig(config({
+      executionTimeoutMs: 300_001,
+    })),
+    /execution timeout/,
+  );
+});
+
+test('loads only canonical read-only projected Copilot configuration', async () => {
+  const root = await mkdtemp(join(tmpdir(), 'ql3-copilot-config-test-'));
+  const file = join(root, 'config.json');
+  const canonical = canonicalClusterCopilotFailureDiagnosisConfig(config());
+  try {
+    await writeFile(file, canonical, { mode: 0o440 });
+    await chmod(file, 0o440);
+    assert.deepEqual(
+      await loadClusterCopilotFailureDiagnosisConfig(file),
+      normalizeClusterCopilotFailureDiagnosisConfig(config()),
+    );
+
+    await chmod(file, 0o640);
+    await writeFile(file, Buffer.from(`${JSON.stringify(config(), null, 2)}\n`), {
+      mode: 0o440,
+    });
+    await chmod(file, 0o440);
+    await assert.rejects(
+      loadClusterCopilotFailureDiagnosisConfig(file),
+      /not canonical/,
+    );
+
+    await chmod(file, 0o640);
+    await writeFile(file, canonical, { mode: 0o640 });
+    await chmod(file, 0o640);
+    await assert.rejects(
+      loadClusterCopilotFailureDiagnosisConfig(file),
+      ClusterCopilotFailureDiagnosisCompositionError,
+    );
+  } finally {
+    canonical.fill(0);
+    await rm(root, { recursive: true, force: true });
+  }
+});
diff --git a/scripts/ql3-cluster-dependency-audit.cjs b/scripts/ql3-cluster-dependency-audit.cjs
index aaed08d0..204e9447 100644
--- a/scripts/ql3-cluster-dependency-audit.cjs
+++ b/scripts/ql3-cluster-dependency-audit.cjs
@@ -1163,6 +1163,9 @@ function auditSourceImports(root, packagePath, findings) {
         const clusterAiImports = Object.freeze({
           'src/aiCli.ts': Object.freeze(['@qinglong/ai/profile']),
           'src/application-runtime/aiProductionApplication.ts': Object.freeze([
+            '@qinglong/ai/durable-model-invocation',
+            '@qinglong/ai/failure-diagnosis-application',
+            '@qinglong/ai/failure-diagnosis-model-execution',
             '@qinglong/ai/plugin-package-prompt-output-projected-keyring',
             '@qinglong/ai/postgres-model-provider-credential-storage',
             '@qinglong/ai/postgres-plugin-package-prompt-application',
@@ -1171,6 +1174,17 @@ function auditSourceImports(root, packagePath, findings) {
             '@qinglong/ai/projected-model-provider-secret-material',
             '@qinglong/ai/provider-credential',
           ]),
+          'src/application-runtime/copilot/failureDiagnosisComposition.ts':
+            Object.freeze([
+              '@qinglong/ai/failure-diagnosis-application',
+              '@qinglong/ai/failure-diagnosis-execution-admission',
+              '@qinglong/ai/failure-diagnosis-model-execution',
+              '@qinglong/ai/failure-diagnosis-tool-execution',
+              '@qinglong/ai/postgres-failure-diagnosis-admission-storage',
+              '@qinglong/ai/postgres-failure-diagnosis-model-execution-storage',
+              '@qinglong/ai/postgres-failure-diagnosis-tool-execution-storage',
+              '@qinglong/ai/profile',
+            ]),
         });
         const sourceRelative = path.relative(packageDirectory, filePath);
         if (!clusterAiImports[sourceRelative]?.includes(specifier)) {
diff --git a/scripts/ql3-cluster-deployment-audit.cjs b/scripts/ql3-cluster-deployment-audit.cjs
index 534d1465..8431655d 100644
--- a/scripts/ql3-cluster-deployment-audit.cjs
+++ b/scripts/ql3-cluster-deployment-audit.cjs
@@ -1311,6 +1311,28 @@ function assertClusterAiComponent(readFile, root, findings) {
       'utf8',
     ),
   );
+  const copilotComponentDirectory = path.join(
+    root,
+    'deploy/kubernetes/ql3-cluster/components/cluster-ai-copilot',
+  );
+  const copilotComponent = yaml.load(
+    readFile(path.join(copilotComponentDirectory, 'kustomization.yaml'), 'utf8'),
+  );
+  const copilotPatch = yaml.load(
+    readFile(path.join(copilotComponentDirectory, 'deployment-patch.yaml'), 'utf8'),
+  );
+  const copilotConfig = yaml.load(
+    readFile(path.join(copilotComponentDirectory, 'copilot-configmap.yaml'), 'utf8'),
+  );
+  const copilotOverlay = yaml.load(
+    readFile(
+      path.join(
+        root,
+        'deploy/kubernetes/ql3-cluster/overlays/cluster-ai-copilot-example/kustomization.yaml',
+      ),
+      'utf8',
+    ),
+  );
   if (
     component?.kind !== 'Component' ||
     JSON.stringify(component?.resources) !==
@@ -1326,6 +1348,156 @@ function assertClusterAiComponent(readFile, root, findings) {
     );
   }
 
+  const copilotPod = objectAt(copilotPatch, ['spec', 'template', 'spec']);
+  const copilotContainer = namedEntry(
+    copilotPod?.containers,
+    'cluster-control',
+  );
+  const copilotEnv = environmentByName(copilotContainer);
+  const copilotProjections = [
+    [
+      'cluster-ai-copilot-config',
+      '/var/run/qinglong3/ai/copilot-config',
+      'configMap',
+      'ql3-cluster-ai-copilot',
+      'config.json',
+    ],
+    [
+      'cluster-ai-copilot-invocation-keyring',
+      '/var/run/secrets/qinglong3/ai/copilot-invocation-keyring',
+      'secret',
+      'ql3-cluster-ai-copilot-invocation-keyring',
+      'keyring.json',
+    ],
+    [
+      'cluster-ai-copilot-result-keyring',
+      '/var/run/secrets/qinglong3/ai/copilot-result-keyring',
+      'secret',
+      'ql3-cluster-ai-copilot-result-keyring',
+      'keyring.json',
+    ],
+    [
+      'cluster-ai-copilot-output-keyring',
+      '/var/run/secrets/qinglong3/ai/copilot-output-keyring',
+      'secret',
+      'ql3-cluster-ai-copilot-output-keyring',
+      'keyring.json',
+    ],
+  ];
+  const copilotProjectionInvalid = copilotProjections.some(
+    ([name, mountPath, kind, authorityName, key]) => {
+      const mount = namedEntry(copilotContainer?.volumeMounts, name);
+      const volume = namedEntry(copilotPod?.volumes, name);
+      const projection = volume?.[kind];
+      return (
+        mount?.mountPath !== mountPath ||
+        mount?.readOnly !== true ||
+        projection?.name !== authorityName &&
+          projection?.secretName !== authorityName ||
+        projection?.defaultMode !== 0o440 ||
+        projection?.optional === true ||
+        JSON.stringify(projection?.items) !==
+          JSON.stringify([{ key, path: key }])
+      );
+    },
+  );
+  if (
+    copilotComponent?.kind !== 'Component' ||
+    JSON.stringify(copilotComponent?.resources) !==
+      JSON.stringify(['copilot-configmap.yaml']) ||
+    JSON.stringify(copilotComponent?.patches) !==
+      JSON.stringify([{ path: 'deployment-patch.yaml' }]) ||
+    copilotPatch?.kind !== 'Deployment' ||
+    copilotPatch?.metadata?.name !== 'ql3-cluster-control' ||
+    copilotPod?.serviceAccountName !== undefined ||
+    copilotPod?.automountServiceAccountToken !== undefined ||
+    copilotPod?.containers?.length !== 1 ||
+    copilotContainer?.image !== undefined ||
+    copilotContainer?.env?.length !== 5 ||
+    copilotContainer?.volumeMounts?.length !== 4 ||
+    copilotPod?.volumes?.length !== 4 ||
+    copilotProjectionInvalid
+  ) {
+    findings.push(
+      finding(
+        'QL3_CLUSTER_AI_COPILOT_PROJECTION',
+        'Cluster Copilot must remain an explicit component with one canonical ConfigMap and three independent required read-only 0440 keyring projections',
+      ),
+    );
+  }
+  for (const [name, expected] of [
+    ['QL3_CLUSTER_AI_COPILOT_ENABLED', 'true'],
+    [
+      'QL3_CLUSTER_AI_COPILOT_CONFIG_FILE',
+      '/var/run/qinglong3/ai/copilot-config/config.json',
+    ],
+    [
+      'QL3_CLUSTER_AI_COPILOT_INVOCATION_KEYRING_ROOT',
+      '/var/run/secrets/qinglong3/ai/copilot-invocation-keyring',
+    ],
+    [
+      'QL3_CLUSTER_AI_COPILOT_RESULT_KEYRING_ROOT',
+      '/var/run/secrets/qinglong3/ai/copilot-result-keyring',
+    ],
+    [
+      'QL3_CLUSTER_AI_COPILOT_OUTPUT_KEYRING_ROOT',
+      '/var/run/secrets/qinglong3/ai/copilot-output-keyring',
+    ],
+  ]) {
+    if (copilotEnv.get(name)?.value !== expected) {
+      findings.push(
+        finding(
+          'QL3_CLUSTER_AI_COPILOT_ENVIRONMENT',
+          `${name} must be fixed to the reviewed projected authority ${expected}`,
+        ),
+      );
+    }
+  }
+  const copilotConfigText = copilotConfig?.data?.['config.json'];
+  let parsedCopilotConfig;
+  try {
+    parsedCopilotConfig = JSON.parse(copilotConfigText);
+  } catch {
+    parsedCopilotConfig = undefined;
+  }
+  if (
+    copilotConfig?.kind !== 'ConfigMap' ||
+    copilotConfig?.metadata?.name !== 'ql3-cluster-ai-copilot' ||
+    typeof copilotConfigText !== 'string' ||
+    `${JSON.stringify(parsedCopilotConfig)}\n` !== copilotConfigText ||
+    parsedCopilotConfig?.schema !==
+      'qinglong/cluster-copilot-failure-diagnosis-config@v1' ||
+    parsedCopilotConfig?.egressPolicy?.schema !==
+      'qinglong/copilot-model-egress-policy@v1'
+  ) {
+    findings.push(
+      finding(
+        'QL3_CLUSTER_AI_COPILOT_CONFIG',
+        'Cluster Copilot configuration must remain canonical, bounded and explicitly versioned',
+      ),
+    );
+  }
+  const copilotOverlayImage = copilotOverlay?.images?.[0];
+  if (
+    JSON.stringify(copilotOverlay?.components) !==
+      JSON.stringify([
+        '../../components/cluster-ai',
+        '../../components/cluster-ai-copilot',
+      ]) ||
+    copilotOverlayImage?.name !== 'qinglong3-cluster-control-ai' ||
+    copilotOverlayImage?.newName !==
+      'registry.example.com/qinglong/qinglong3-cluster-control-ai' ||
+    !/^sha256:[0-9a-f]{64}$/.test(copilotOverlayImage?.digest ?? '') ||
+    'newTag' in (copilotOverlayImage ?? {})
+  ) {
+    findings.push(
+      finding(
+        'QL3_CLUSTER_AI_COPILOT_OVERLAY',
+        'The Copilot overlay must compose explicit AI and Copilot components and independently pin the Cluster AI image digest',
+      ),
+    );
+  }
+
   const promptOutputPod = objectAt(promptOutputPatch, [
     'spec',
     'template',
@@ -1564,7 +1736,11 @@ function assertClusterAiComponent(readFile, root, findings) {
     ) ||
     namedEntry(basePod?.volumes, 'cluster-ai-provider-authority') ||
     namedEntry(basePod?.volumes, 'cluster-ai-provider-secrets') ||
-    namedEntry(basePod?.volumes, 'cluster-ai-prompt-output-keyring')
+    namedEntry(basePod?.volumes, 'cluster-ai-prompt-output-keyring') ||
+    [...copilotProjections].some(([name]) =>
+      namedEntry(baseContainer?.volumeMounts, name) ||
+      namedEntry(basePod?.volumes, name),
+    )
   ) {
     findings.push(
       finding(
diff --git a/test/back/ql3PackageBoundaryAudit.test.cjs b/test/back/ql3PackageBoundaryAudit.test.cjs
index e2a82dc2..9456c7d1 100644
--- a/test/back/ql3PackageBoundaryAudit.test.cjs
+++ b/test/back/ql3PackageBoundaryAudit.test.cjs
@@ -268,10 +268,10 @@ test('current QL3 workspace has exactly eighteen reviewed package boundaries', (
     {
       path: 'packages/ql3-ai',
       name: '@qinglong/ai',
-      sourceFiles: 183,
+      sourceFiles: 187,
       rootSourceFiles: 1,
       rootSourceLines: 16,
-      nestedSourceFiles: 182,
+      nestedSourceFiles: 186,
       rootSourceFileHardCap: 1,
       rootSourceLineHardCap: 16,
       rootSourceFileRoles: {
@@ -385,10 +385,10 @@ test('current QL3 workspace has exactly eighteen reviewed package boundaries', (
       rootSourceFileRoles: clusterControl.rootSourceFileRoles,
     },
     {
-      sourceFiles: 58,
+      sourceFiles: 59,
       rootSourceFiles: 2,
       rootSourceLines: 195,
-      nestedSourceFiles: 56,
+      nestedSourceFiles: 57,
       rootSourceFileRoles: {
         'aiCli.ts': 'binary_entry',
         'cli.ts': 'binary_entry',