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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+Hohoff Editor — an Electron desktop app for novel editing with AI-powered writing analysis. Built with React 18, TypeScript, CodeMirror 6, and Zustand. Uses the Anthropic Claude API for chat and text analysis features.
+
+## Commands
+
+- `npm run dev` — Start Electron dev server with hot reload
+- `npm run build` — Production build (outputs to `out/`)
+- `npm run typecheck` — Type-check both Node and browser TypeScript configs
+- `npm run preview` — Preview production build
+
+No test runner or linter is configured.
+
+## Architecture
+
+**Electron three-process model:**
+
+- **Main process** (`src/main/`) — Node.js environment. Handles file I/O (`fileSystem.ts`), Claude API streaming (`aiService.ts`), and IPC handlers (`ipcHandlers.ts`).
+- **Preload** (`src/preload/index.ts`) — Bridges main↔renderer via `contextBridge`. Exposes `window.api.*` methods.
+- **Renderer** (`src/renderer/`) — React app with CodeMirror editor. All file/AI operations go through `window.api.*` IPC calls, never direct Node access.
+
+**State management:** Single Zustand store (`src/renderer/store/editorStore.ts`) holds all app state — active file, chat history (per-file), annotations (per-file), UI preferences. State auto-persists to `.session.json` in the draft directory with 1500ms debounce.
+
+**Key renderer components:**
+
+| Directory | Purpose |
+|-----------|---------|
+| `components/Editor/` | CodeMirror 6 markdown editor with custom annotation decorations and theme compartments |
+| `components/AIChat/` | Streaming chat interface, per-file conversation history, attachment support (images/PDF/text) |
+| `components/Feedback/` | AI annotation panel — highlights parsed from AI responses, hover tooltips, one-click apply |
+| `components/FileTree/` | Drag-and-drop file navigation with custom ordering (`.order.json`) |
+| `components/Revisions/` | Version history with word count tracking, stored in `.revisions/` directory |
+| `components/Toolbar/` | Analysis mode triggers (passive voice, consistency, style, critique) |
+
+## Key Patterns
+
+**IPC flow:** Renderer calls `window.api.method()` → preload forwards via `ipcRenderer.invoke()` → main process handler in `ipcHandlers.ts` executes and returns result. AI streaming uses event-based IPC (`ai:chunk` events).
+
+**CodeMirror annotations:** Custom `StateField` tracks annotation positions. Positions are remapped through document changes via `tr.changes.mapPos()`. Annotations auto-dismiss 1.2s after the user edits the annotated region. Apply/dismiss actions integrate with CodeMirror undo history via `invertedEffects`.
+
+**Annotation parsing** (`src/renderer/utils/annotationParser.ts`): AI responses are parsed for quoted text, which is matched against document content (exact match first, then normalized whitespace fallback). Each quote becomes a positioned annotation with type, message, and optional suggestion.
+
+**Path alias:** `@renderer/*` resolves to `src/renderer/*` (configured in both Vite and tsconfig.web.json).
+
+## Environment
+
+Requires `.env.local` in project root with:
+- `ANTHROPIC_API_KEY` — Claude API key
+- `DRAFT_PATH` — Absolute path to the directory containing markdown draft files
+
+## TypeScript Configuration
+
+Two separate tsconfig files referenced from root `tsconfig.json`:
+- `tsconfig.node.json` — Main and preload processes (Node.js environment)
+- `tsconfig.web.json` — Renderer process (browser environment, has `@renderer/*` path alias)