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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Language Conventions
+
+- **Output / explanations:** Russian
+- **Code:** English
+- **Comments, commit messages:** Russian
+
+## Commands
+
+```bash
+# Build
+dotnet build
+
+# Run (starts TUI + HTTP MCP endpoint on port 5000)
+dotnet run --project LazyBear.MCP
+
+# Test MCP tool wiring (only needed after changing transport or tool registration)
+npx @modelcontextprotocol/inspector dotnet run --project LazyBear.MCP
+```
+
+There are **no test projects**. After making changes, run `dotnet build`. If MCP wiring changed (new tool, new module, transport changes), also run the inspector.
+
+Port is controlled via the `ASPNETCORE_URLS` environment variable (default `http://localhost:5000`). Ignore `launchSettings.json` — it shows a different port that is not used.
+
+## Architecture
+
+LazyBear is a .NET 10 MCP server exposing Jira, Confluence, and Kubernetes integrations to AI clients. It runs in two simultaneous modes that share a single DI container:
+
+1. **TUI (foreground)** — RazorConsole terminal UI (`App.razor`), owns the console, handles keyboard navigation
+2. **HTTP MCP endpoint (background)** — `McpWebHostedService` runs as a hosted service, serves MCP tool calls on port 5000
+
+Both share the same singletons: `ToolRegistryService`, `InMemoryLogSink`, and the three client providers.
+
+### Plugin System (IToolModule)
+
+Each integration implements `IToolModule` (in `Services/ToolRegistry/IToolModule.cs`) and declares its `ModuleName`, `ToolNames[]`, and `Description`. Tool classes are auto-discovered at startup via reflection using `WithToolsFromAssembly()` — classes are annotated with `[McpServerToolType]`, methods with `[McpServerTool]`. Registering a new module requires only: implement `IToolModule`, create tool classes with attributes, and add DI registration in `Program.cs`.
+
+### ToolRegistryService
+
+Singleton that tracks enabled/disabled state for both modules and individual tools at runtime (no restart needed). Uses `ConcurrentDictionary` for thread safety. Fires `StateChanged` event on toggles; TUI components subscribe to re-render. Tool keys use the format `"ModuleName::ToolName"`.
+
+### Provider Pattern
+
+Each client (`K8sClientProvider`, `JiraClientProvider`, `ConfluenceClientProvider`) is a lazy singleton. If initialization fails (missing config, unreachable endpoint), it captures an `InitializationError` string. **Tools return error strings instead of throwing exceptions** — this is intentional so MCP clients see the configuration issue gracefully.
+
+### Logging
+
+`InMemoryLogSink` maintains a 500-entry circular `ConcurrentQueue`. All .NET logs flow through `InMemoryLoggerProvider` → sink → `OnLog` event → TUI Logs tab live view.
+
+### TUI Navigation
+
+Tabs: Overview → Logs → Settings (switch with `Tab`/`Shift+Tab`). In Settings: arrow keys navigate the module→tool tree, `Space` toggles enable/disable, `Enter` expands/collapses. In Overview, `Enter` on a module jumps to its Settings entry.
+
+## Configuration Gotchas
+
+- **`Jira:Url`** is required; if missing, all Jira tools return string errors
+- **K8s kubeconfig fallback order:** explicit `Kubernetes:KubeconfigPath` → `~/.kube/config` → in-cluster config
+- **Source of truth:** `Program.cs`, not `README.md` (README is aspirational)
+- `Pages/` directory exists but Razor Pages are **not enabled** in `Program.cs` — do not use them
+
+## Key Dependencies
+
+| Package | Role |
+|---------|------|
+| `ModelContextProtocol.AspNetCore` 1.2.0 | HTTP MCP transport |
+| `KubernetesClient` 19.0.2 | K8s API |
+| `RestSharp` 112.0.0 | Jira / Confluence HTTP |
+| `RazorConsole.Core` 0.5.0 | Terminal UI framework |
+| `Polly` 8.4.2 | Retry/resilience policies |