Building Your Own Deep Research with LangChain

Core User Research Workflow

graph TD
    subgraph "Start"
        A[User Input: Research Question & Target Demographic]
    end

    subgraph "LangGraph Workflow"
        B(Configuration Node 
 Generates interview questions)
        C(Persona Generation Node 
 Creates synthetic user personas)

        subgraph "Interview Loop"
            D(Interview Node 
 Conducts Q&A with a persona)
            E{Interview Router 
 All personas interviewed?}
        end

        F(Synthesis Node 
 Analyzes all interviews and generates insights)
    end

    subgraph "End"
        G[Output: Comprehensive Research Report]
    end

    A --> B
    B --> C
    C --> D
    D --> E
    E -- No --> D
    E -- Yes --> F
    F --> G

Optional Workflow with Follow-Up Questions

graph TD
    subgraph "Start"
        A[User Input: Research Question & Target Demographic]
    end

    subgraph "LangGraph Workflow"
        B(Configuration Node 
 Generates interview questions)
        C(Persona Generation Node 
 Creates synthetic user personas)

        subgraph "Interview Loop (for each persona)"
            D(Interview Node 
 1. Asks standard questions in a loop 
 2. Asks one follow-up question)
        end

        E{Interview Router 
 All personas interviewed?}

        F(Synthesis Node 
 Analyzes all interviews and generates insights)
    end

    subgraph "End"
        G[Output: Comprehensive Research Report]
    end

    A --> B
    B --> C
    C --> D
    D --> E
    E -- No (Next Persona) --> D
    E -- Yes --> F
    F --> G

Source: How to Build Advanced AI Agents