CopilotKit <> PydanticAI AG-UI Canvas Starter
This is a starter template for building AI-powered canvas applications using PydanticAI and CopilotKit. It provides a modern Next.js application with an integrated PydanticAI agent that manages a visual canvas of interactive cards with real-time AI synchronization.
https://github.com/user-attachments/assets/2a4ec718-b83b-4968-9cbe-7c1fe082e958
🚀 Key Features
- Visual Canvas Interface: Drag-free canvas displaying cards in a responsive grid layout
- Four Card Types:
- Project: Includes text fields, dropdown, date picker, and checklist
- Entity: Features text fields, dropdown, and multi-select tags
- Note: Simple rich text content area
- Chart: Visual metrics with percentage-based bar charts
- Real-time AI Sync: Bidirectional synchronization between the AI agent and UI canvas
- Multi-step Planning: AI can create and execute plans with visual progress tracking
- Human-in-the-Loop (HITL): Intelligent interrupts for clarification when needed
- JSON View: Toggle between visual canvas and raw JSON state
- Responsive Design: Optimized for both desktop (sidebar chat) and mobile (popup chat)
Prerequisites
- Node.js 18+
- Python 3.8+
- OpenAI API Key (for the PydanticAI agent)
- Any of the following package managers:
Note: This repository ignores lock files (package-lock.json, yarn.lock, pnpm-lock.yaml, bun.lockb) to avoid conflicts between different package managers. Each developer should generate their own lock file using their preferred package manager. After that, make sure to delete it from the .gitignore.
Getting Started
- Install dependencies using your preferred package manager:
# Using pnpm (recommended)
pnpm install
# Using npm
npm install
# Using yarn
yarn install
# Using bun
bun install
- Install Python dependencies for the PydanticAI agent:
# Using pnpm
pnpm install:agent
# Using npm
npm run install:agent
# Using yarn
yarn install:agent
# Using bun
bun run install:agent
Note: This will automatically setup a
.venv(virtual environment) inside theagentdirectory.To activate the virtual environment manually, you can run:
source agent/.venv/bin/activate
- Set up your OpenAI API key:
export OPENAI_API_KEY="your-openai-api-key-here"
- Start the development server:
# Using pnpm
pnpm dev
# Using npm
npm run dev
# Using yarn
yarn dev
# Using bun
bun run dev
This will start both the UI and agent servers concurrently.
Getting Started with the Canvas
Once the application is running, you can:
-
Create Cards: Use the "New Item" button or ask the AI to create cards
- "Create a new project"
- "Add an entity and a note"
- "Create a chart with sample metrics"
-
Edit Cards: Click on any field to edit directly, or ask the AI
- "Set the project field1 to 'Q1 Planning'"
- "Add a checklist item 'Review budget'"
- "Update the chart metrics"
-
Execute Plans: Give the AI multi-step instructions
- "Create 3 projects with different priorities and add 2 checklist items to each"
- The AI will create a plan and execute it step by step with visual progress
-
View JSON: Toggle between the visual canvas and JSON view using the button at the bottom
Available Scripts
The following scripts can also be run using your preferred package manager:
dev- Starts both UI and agent servers in development modedev:debug- Starts development servers with debug logging enableddev:ui- Starts only the Next.js UI serverdev:agent- Starts only the PydanticAI agent serverbuild- Builds the Next.js application for productionstart- Starts the production serverlint- Runs ESLint for code lintinginstall:agent- Installs Python dependencies for the agent
Architecture Overview
graph TB
subgraph "Frontend (Next.js)"
UI[Canvas UI<br/>page.tsx]
Actions[Frontend Actions<br/>useCopilotAction]
State[State Management<br/>useCoAgent]
Chat[CopilotChat]
end
subgraph "Backend (Python)"
Agent[PydanticAI Agent<br/>agent.py]
Tools[Backend Tools<br/>- set_plan<br/>- update_plan_progress<br/>- complete_plan]
AgentState[Canvas State<br/>StateDeps]
Model[LLM<br/>GPT-4o]
end
subgraph "Communication"
Runtime[CopilotKit Runtime<br/>:8000]
end
UI <--> State
State <--> Runtime
Chat <--> Runtime
Actions --> Runtime
Runtime <--> Agent
Agent --> Tools
Agent --> AgentState
Agent --> Model
style UI fill:#e1f5fe
style Agent fill:#fff3e0
style Runtime fill:#f3e5f5
click UI "https://github.com/CopilotKit/CopilotKit/blob/main/examples/canvas/pydantic-ai/src/app/page.tsx"
click Agent "https://github.com/CopilotKit/CopilotKit/blob/main/examples/canvas/pydantic-ai/agent/agent.py"
Frontend (Next.js + CopilotKit)
The main UI component is in src/app/page.tsx. It includes:
- Canvas Management: Visual grid of cards with create, read, update, and delete operations
- State Synchronization: Uses
useCoAgenthook for real-time state sync with the agent - Frontend Actions: Exposed as tools to the AI agent via
useCopilotAction - Plan Visualization: Shows multi-step plan execution with progress indicators
- HITL (Tool-based): Uses
useCopilotActionwithrenderAndWaitForResponsefor disambiguation prompts (e.g., choosing an item or card type)
Backend (PydanticAI Agent)
The agent logic is in agent/agent.py. It features:
- State Management: Uses
StateDeps[CanvasState]for typed state management - Tool Integration: Backend tools decorated with
@agent.toolfor planning and state updates - Strict Grounding: Enforces data consistency by always using shared state as truth
- Dynamic Instructions: Uses
@agent.instructionsto provide context-aware guidance - AG-UI Integration: Converts to FastAPI app with
agent.to_ag_ui()for seamless integration - Type Safety: Leverages Pydantic models for all data structures
Card Field Schema
Each card type has specific fields defined in the agent:
- Project: field1 (text), field2 (select), field3 (date), field4 (checklist)
- Entity: field1 (text), field2 (select), field3 (tags), field3_options (available tags)
- Note: field1 (textarea content)
- Chart: field1 (array of metrics with label and value 0-100)
Data Flow
sequenceDiagram
participant User
participant UI as Canvas UI
participant CK as CopilotKit
participant Agent as PydanticAI Agent
participant Tools
User->>UI: Interact with canvas
UI->>CK: Update state via useCoAgent
CK->>Agent: Send state + message
Agent->>Agent: Process with GPT-4o
Agent->>Tools: Execute tools
Tools-->>Agent: Return results
Agent->>CK: Return updated state
CK->>UI: Sync state changes
UI->>User: Display updates
Note over Agent: Maintains ground truth
Note over UI,CK: Real-time bidirectional sync
Customization Guide
Adding New Card Types
- Define the data schema in
src/lib/canvas/types.ts - Add the card type to the
CardTypeunion - Create rendering logic in
src/components/canvas/CardRenderer.tsx - Update the agent's Pydantic models in
agent/agent.py - Add corresponding frontend actions in
src/app/page.tsx
Modifying Existing Cards
- Field definitions are in the agent's Pydantic models (e.g.,
ProjectData,EntityData) - UI components are in
CardRenderer.tsx - Frontend actions follow the pattern:
set[Type]Field[Number]
Extending the Agent
PydanticAI makes it easy to extend the agent with:
- New Tools: Add functions decorated with
@agent.tool - Custom Instructions: Modify the
@agent.instructionsfunction - State Extensions: Add fields to the
CanvasStatemodel - Type Safety: All changes benefit from Pydantic's type validation
Styling
- Global styles:
src/app/globals.css - Component styles use Tailwind CSS with shadcn/ui components
- Theme colors can be modified via CSS custom properties
📚 Documentation
- PydanticAI Documentation - Learn more about PydanticAI and its features
- CopilotKit Documentation - Explore CopilotKit's capabilities
- Next.js Documentation - Learn about Next.js features and API
Contributing
Feel free to submit issues and enhancement requests! This starter is designed to be easily extensible.
License
This project is licensed under the MIT License - see the LICENSE file for details.
Troubleshooting
Agent Connection Issues
If you see "I'm having trouble connecting to my tools", make sure:
- The PydanticAI agent is running on port 8000 (check terminal output)
- Your OpenAI API key is set correctly as an environment variable
- Both servers started successfully (UI and agent)
Port Already in Use
If you see "[Errno 48] Address already in use":
- The agent might still be running from a previous session
- Kill the process using the port:
lsof -ti:8000 | xargs kill -9 - For the UI port:
lsof -ti:3000 | xargs kill -9
State Synchronization Issues
If the canvas and AI seem out of sync:
- Check the browser console for errors
- Ensure all frontend actions are properly registered
- Verify the agent is using the latest shared state (not cached values)
Python Dependencies
If you encounter Python import errors:
cd agent
pip install -r requirements.txt
Virtual Environment Issues
If the virtual environment is not activated properly:
cd agent
source .venv/bin/activate # On macOS/Linux
# or
.venv\Scripts\activate # On Windows
Dependency Conflicts
If issues persist, recreate the virtual environment:
cd agent
rm -rf .venv
python -m venv .venv
.venv/bin/pip install --upgrade pip
.venv/bin/pip install -r requirements.txt
Important
Some features are still under active development and may not yet work as expected. If you encounter a problem using this template, please report an issue to this repository.