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docs/USER_GUIDE.md

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+<!-- docs/USER_GUIDE.md -->
+
+# User Guide
+
+## Sidebar
+
+- **Model**: Select among HF, OpenAI, Gemini, Groq, and Fireworks models.  
+- **Input**: Describe your app or paste code/text.  
+- **Generate**: Click to invoke the AI pipeline.
+
+## Tabs
+
+- **Code**: View generated code (editable).  
+- **Preview**: Live HTML preview (for web outputs).  
+- **History**: Conversation log with assistant.
+
+## Files & Plugins
+
+- Upload reference files (PDF, DOCX, images) for extraction.  
+- Use **Plugins** to integrate GitHub, Slack, DB queries, etc.  
+
+---
+
+```markdown
+<!-- docs/API_REFERENCE.md -->
+
+# API Reference
+
+## `models.py`
+
+### `ModelInfo`
+- `name: str`  
+- `id: str`  
+- `description: str`  
+- `default_provider: str`
+
+### `find_model(identifier: str) -> Optional[ModelInfo]`
+
+## `inference.py`
+
+### `chat_completion(model_id, messages, provider=None, max_tokens=4096) -> str`
+
+### `stream_chat_completion(model_id, messages, provider=None, max_tokens=4096) -> Generator[str]`
+
+---
+
+```markdown
+<!-- docs/ARCHITECTURE.md -->
+
+# Architecture
+