Documentation Index
Fetch the complete documentation index at: https://chatjs.dev/docs/llms.txt
Use this file to discover all available pages before exploring further.
Directory Overview
├── app/ # Next.js App Router
│ ├── (auth)/ # Auth routes (login, register)
│ ├── (chat)/ # Main chat interface
│ ├── api/ # API routes (chat, auth, trpc)
│ └── actions/ # Server Actions
│
├── components/
│ ├── ai-elements/ # AI Elements registry components
│ ├── chat/ # Chat UI components
│ ├── part/ # Tool part renderers
│ ├── settings/ # Settings pages
│ └── ui/ # shadcn/ui components
│
├── lib/
│ ├── ai/ # AI SDK integration, tools, prompts
│ │ └── gateways/ # Gateway abstraction (Vercel, OpenRouter)
│ ├── db/ # Database schema, queries, and data access
│ ├── models/ # Model types and utilities
│ └── stores/ # Zustand stores
│
├── trpc/ # tRPC routers and procedures
├── hooks/ # React hooks
├── providers/ # React context providers
├── evals/ # AI evaluation tests
└── scripts/ # Build and dev scripts
Key Files
| File | Purpose |
|---|
chat.config.ts | Central configuration (features, models, branding) |
lib/config.ts | Parsed config export with defaults |
lib/env.ts | Environment variable validation (t3-env) |
lib/auth.ts | Better Auth server configuration |
lib/auth-client.ts | Better Auth client configuration |
lib/db/schema.ts | Drizzle ORM database schema |
proxy.ts | Route protection middleware |
App Router Structure
Route Groups
(auth) - Authentication pages, shared layout without chat UI(chat) - Main application, chat interface layout
API Routes
app/api/
├── auth/[...all]/ # Better Auth handler
├── chat/ # AI streaming endpoint
├── trpc/[trpc]/ # tRPC handler
└── cron/ # Scheduled tasks
Components Architecture
UI Layer
components/
├── ui/ # Base components (shadcn/ui)
│ └── extra/ # Local tweaks on shadcn components
├── ai-elements/ # AI Elements components
│ └── extra/ # Local tweaks on AI Elements
├── chat/ # Chat-specific components
└── part/ # Tool result renderers
Part Components
Tool results are rendered by part components in components/part/. Each tool has a corresponding component:
components/part/
├── web-search-part.tsx
├── code-execution-part.tsx
├── image-generation-part.tsx
└── ...
Library Structure
AI Integration
lib/ai/
├── gateways/ # Gateway abstraction
│ ├── types.ts # GatewayProvider interface
│ ├── index.ts # Gateway registry + getActiveGateway()
│ ├── vercel-gateway.ts
│ └── openrouter-gateway.ts
├── models.ts # Model fetching and caching
├── models.generated.ts # Fallback model list
├── tools/ # Tool definitions
│ ├── web-search.ts
│ ├── code-execution.ts
│ └── ...
└── prompts/ # System prompts
Data Layer
lib/
├── db/
│ ├── schema.ts # Drizzle schema
│ ├── queries.ts # Database queries (chats, messages, users)
│ ├── credits.ts # Credit balance queries
│ └── client.ts # Database connection
└── stores/ # Client state (Zustand)
Configuration Flow
chat.config.ts # Define features, models, branding
↓
lib/config.ts # Parse defaults and export config
↓
lib/env.ts # Validate environment variables
↓
Runtime # Features toggle based on config + env
Data Flow
Client Component
↓
tRPC Procedure (or Server Action)
↓
Database Queries (lib/db/)
↓
Drizzle ORM
↓
PostgreSQL
AI Streaming Flow
Client (useChat hook)
↓
POST /api/chat
↓
Vercel AI SDK (streamText)
↓
Gateway Abstraction → Provider (OpenAI, Anthropic, etc.)
↓
Stream response with tool calls
↓
Tool execution (if needed)
↓
Client renders parts
