App Builder is an AI-powered coding assistant built with LangGraph that functions like a multi-agent developer team.
It can take a natural language request and generate a complete, working project — file by file — using real developer workflows.

App Builder consists of three main agents working together in a state-based graph:

• Planner Agent – Analyzes user input and creates a structured project plan.
• Architect Agent – Breaks down the plan into detailed engineering tasks for each file.
• Coder Agent – Implements each task using tools like a real developer (reads, writes, and manages files).

Each agent communicates through a shared state that keeps updating as the workflow progresses.

The system uses LangGraph to connect agents through a directed graph:

1. Planner ➜ Architect ➜ Coder
2. The Planner creates a project plan.
3. The Architect converts the plan into step-by-step tasks.
4. The Coder executes each step — reading, writing, and updating files until the project is complete.
5. The process ends automatically when all tasks are done.

• Field: Decorator for model attributes, allows setting defaults, validations, and docs.
• END: Special marker indicating the end of the LangGraph workflow.
• StateGraph: Core class used to build and manage the state-based execution graph.
• set_debug(True): Enables detailed debugging info for LangChain execution.
• set_verbose(True): Enables step-by-step logs of LangChain flow.

• uv installed (for virtual environment management).
• A Groq account and API key — get one here.

# 1. Create a virtual environment
uv venv
source .venv/bin/activate

# 2. Install dependencies
uv pip install -r pyproject.toml

# 3. Configure environment variables
cp .sample_env .env
# Edit .env and add your Groq API key

# 4. Run the app
python main.py