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+# headlamp-tns-csi-plugin
+
+Headlamp plugin for tns-csi CSI driver visibility and kbench benchmarking.
+
+## Project
+
+- **Plugin name**: `headlamp-tns-csi-plugin`
+- **Provisioner**: `tns.csi.io`
+- **Upstream driver**: https://github.com/fenio/tns-csi
+- **Benchmark tool**: https://github.com/longhorn/kbench
+- **Reference plugin**: `../headlamp-polaris-plugin`
+
+## Commands
+
+```bash
+npm start          # dev server with hot reload
+npm run build      # production build
+npm run package    # package for headlamp
+npm run tsc        # TypeScript type check (no emit)
+npm run lint       # ESLint
+npm test           # vitest run
+npm run test:watch # vitest watch mode
+```
+
+## Architecture
+
+```
+src/
+├── index.tsx                    # Plugin entry: registerRoute, registerSidebarEntry, etc.
+├── api/
+│   ├── k8s.ts                   # Types + filtering helpers (provisioner: tns.csi.io)
+│   ├── metrics.ts               # Prometheus text format parser
+│   ├── kbench.ts                # kbench Job/PVC lifecycle + FIO log parser
+│   └── TnsCsiDataContext.tsx    # Shared React context provider
+└── components/
+    ├── OverviewPage.tsx
+    ├── StorageClassesPage.tsx
+    ├── VolumesPage.tsx
+    ├── SnapshotsPage.tsx
+    ├── MetricsPage.tsx
+    ├── BenchmarkPage.tsx        # ONLY write operation in the plugin
+    ├── DriverStatusCard.tsx
+    └── PVCDetailSection.tsx     # Injected into Headlamp PVC detail view
+```
+
+## Key constants
+
+- Provisioner: `tns.csi.io`
+- Controller pod selector: `app.kubernetes.io/name=tns-csi-driver,app.kubernetes.io/component=controller`
+- Node pod selector: `app.kubernetes.io/name=tns-csi-driver,app.kubernetes.io/component=node`
+- Driver namespace: `kube-system`
+- Metrics port: `8080`
+- kbench image: `yasker/kbench:latest`
+- kbench managed-by label: `app.kubernetes.io/managed-by=headlamp-tns-csi-plugin`
+
+## Code conventions
+
+- Functional React components only — no class components
+- All imports from `@kinvolk/headlamp-plugin/lib` and `@kinvolk/headlamp-plugin/lib/CommonComponents`
+- No additional UI libraries (no MUI direct imports, no Ant Design, etc.)
+- TypeScript strict mode — no `any`, use `unknown` + type guards at API boundaries
+- Slide-in detail panels follow the polaris plugin pattern: URL hash state, Escape to close, backdrop overlay
+- Context provider (`TnsCsiDataProvider`) wraps each route component in `index.tsx`
+- Tests: vitest + @testing-library/react, mock with `vi.mock('@kinvolk/headlamp-plugin/lib', ...)`
+
+## Subagent guidance
+
+When launching subagents for tasks in this repo:
+
+- **Research tasks** (reading files, searching code, exploring GitHub): use `subagent_type: Explore`
+  with tools: Read, Glob, Grep, Bash, WebFetch, GitHub MCP
+- **Implementation tasks** (writing/editing files): use `subagent_type: general-purpose`
+- **Debugging**: use `subagent_type: debugger`
+- **Avoid** launching background agents for open-ended research — do research in the main session
+  using Glob, Grep, Read, and GitHub MCP directly, then delegate scoped write tasks to agents
+- The main session has broader tool approvals than subagent sandboxes; use it for exploration
+
+## Testing
+
+All tests must pass before committing:
+
+```bash
+npm test        # 67 tests across 4 test files
+npm run tsc     # must exit 0
+```
+
+Mock pattern for headlamp APIs:
+```typescript
+vi.mock('@kinvolk/headlamp-plugin/lib', () => ({
+  ApiProxy: { request: vi.fn().mockResolvedValue({ items: [] }) },
+  K8s: {
+    ResourceClasses: {
+      StorageClass: { useList: vi.fn(() => [[], null]) },
+      PersistentVolume: { useList: vi.fn(() => [[], null]) },
+      PersistentVolumeClaim: { useList: vi.fn(() => [[], null]) },
+    },
+  },
+}));
+```