Learn to Generate Reports with LangGraph and AI
Fecha del documento: 04-06-2025

In the current landscape of data analysis and artificial intelligence, the automatic generation of comprehensive and coherent reports represents a significant challenge. While traditional tools allow for data visualization or generating isolated statistics, there is a need for systems that can investigate a topic in depth, gather information from diverse sources, and synthesize findings into a structured and coherent report.
In this practical exercise, we will explore the development of a report generation agent based on LangGraph and artificial intelligence. Unlike traditional approaches based on templates or predefined statistical analysis, our solution leverages the latest advances in language models to:
- Create virtual teams of analysts specialized in different aspects of a topic.
- Conduct simulated interviews to gather detailed information.
- Synthesize the findings into a coherent and well-structured report.
Access the data laboratory repository on Github.
Run the data preprocessing code on Google Colab.
As shown in Figure 1, the complete agent flow follows a logical sequence that goes from the initial generation of questions to the final drafting of the report.
Figure 1. Agent flow diagram.
Application Architecture
The core of the application is based on a modular design implemented as an interconnected state graph, where each module represents a specific functionality in the report generation process. This structure allows for a flexible workflow, recursive when necessary, and with capacity for human intervention at strategic points.
Main Components
The system consists of three fundamental modules that work together:
1. Virtual Analysts Generator
This component creates a diverse team of virtual analysts specialized in different aspects of the topic to be investigated. The flow includes:
- Initial creation of profiles based on the research topic.
- Human feedback point that allows reviewing and refining the generated profiles.
- Optional regeneration of analysts incorporating suggestions.
This approach ensures that the final report includes diverse and complementary perspectives, enriching the analysis.
2. Interview System
Once the analysts are generated, each one participates in a simulated interview process that includes:
- Generation of relevant questions based on the analyst's profile.
- Information search in sources via Tavily Search and Wikipedia.
- Generation of informative responses combining the obtained information.
- Automatic decision on whether to continue or end the interview based on the information gathered.
- Storage of the transcript for subsequent processing.
The interview system represents the heart of the agent, where the information that will nourish the final report is obtained. As shown in Figure 2, this process can be monitored in real time through LangSmith, an open observability tool that allows tracking each step of the flow.
Figure 2. System monitoring via LangGraph. Concrete example of an analyst-interviewer interaction.
3. Report Generator
Finally, the system processes the interviews to create a coherent report through:
- Writing individual sections based on each interview.
- Creating an introduction that presents the topic and structure of the report.
- Organizing the main content that integrates all sections.
- Generating a conclusion that synthesizes the main findings.
- Consolidating all sources used.
The Figure 3 shows an example of the report resulting from the complete process, demonstrating the quality and structure of the final document generated automatically.
Figure 3. View of the report resulting from the automatic generation process to the prompt "Open data in Spain".
What can you learn?
This practical exercise allows you to learn:
Integration of advanced AI in information processing systems:
- How to communicate effectively with language models.
- Techniques to structure prompts that generate coherent and useful responses.
- Strategies to simulate virtual teams of experts.
Development with LangGraph:
- Creation of state graphs to model complex flows.
- Implementation of conditional decision points.
- Design of systems with human intervention at strategic points.
Parallel processing with LLMs:
- Parallelization techniques for tasks with language models.
- Coordination of multiple independent subprocesses.
- Methods for consolidating scattered information.
Good design practices:
- Modular structuring of complex systems.
- Error handling and retries.
- Tracking and debugging workflows through LangSmith.
Conclusions and future
This exercise demonstrates the extraordinary potential of artificial intelligence as a bridge between data and end users. Through the practical case developed, we can observe how the combination of advanced language models with flexible architectures based on graphs opens new possibilities for automatic report generation.
The ability to simulate virtual expert teams, perform parallel research and synthesize findings into coherent documents, represents a significant step towards the democratization of analysis of complex information.
For those interested in expanding the capabilities of the system, there are multiple promising directions for its evolution:
- Incorporation of automatic data verification mechanisms to ensure accuracy.
- Implementation of multimodal capabilities that allow incorporating images and visualizations.
- Integration with more sources of information and knowledge bases.
- Development of more intuitive user interfaces for human intervention.
- Expansion to specialized domains such as medicine, law or sciences.
In summary, this exercise not only demonstrates the feasibility of automating the generation of complex reports through artificial intelligence, but also points to a promising path towards a future where deep analysis of any topic is within everyone's reach, regardless of their level of technical experience. The combination of advanced language models, graph architectures and parallelization techniques opens a range of possibilities to transform the way we generate and consume information.