5 min
In regulated industries such as pharma, insurance, and legal, accuracy, auditability, and scalability are not optional. When evaluating AI solutions for document understanding, two main approaches emerge: a Custom GPT (a fine-tuned or prompt-engineered large language model) and Lettria Knowledge Studio, powered by a GraphRAG architecture.
Both can process text and generate answers. The difference lies in how they handle knowledge, context, and traceability.
Why GraphRAG Delivers More Than a Custom GPT
Lettria’s Knowledge Studio combines document intelligence, knowledge graphs, and retrieval-augmented generation. Instead of relying only on textual embeddings, it builds a structured graph of entities and relationships, enabling explicit reasoning and traceable results.
1. Performance
In pharma or legal contexts, Lettria outperforms Custom GPTs on complex queries. The graph structure allows the system to reason over explicit links (for example, molecule X → effect Y) rather than relying only on pattern recognition within text.
2. Scalability
A Custom GPT is limited by its input size. It can only ingest a few documents before reaching token limits.
Lettria’s architecture ingests and connects tens of thousands of scientific or regulatory documents. This makes it suitable for large-scale research, compliance, or knowledge management environments.
3. Explainability
Every answer generated by Lettria can be traced back to the nodes and sources in the graph that supported it. This ensures full transparency and auditability, a critical capability for compliance and internal validation.
Comparative Overview
When to Choose Each Approach
Bottom Line
A Custom GPT is useful for simple, text-based applications such as internal search or chat assistants.
But when document volume, complexity, or compliance matter, GraphRAG-based architectures like Lettria Knowledge Studio become essential. Here is the type of document you can ingest with Lettria :
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They turn unstructured text into connected, explainable knowledge, enabling enterprises to trust and scale their AI workflows.
Interested in seeing how this works with your own documents?
👉 Request a demo of Lettria Knowledge Studio
Frequently Asked Questions
Yes. Lettria’s platform including Perseus is API-first, so we support over 50 native connectors and workflow automation tools (like Power Automate, web hooks etc,). We provide the speedy embedding of document intelligence into current compliance, audit, and risk management systems without disrupting existing processes or requiring extensive IT overhaul.
It dramatically reduces time spent on manual document parsing and risk identification by automating ontology building and semantic reasoning across large document sets. It can process an entire RFP answer in a few seconds, highlighting all compliant and non-compliant sections against one or multiple regulations, guidelines, or policies. This helps you quickly identify risks and ensure full compliance without manual review delays.
Lettria focuses on document intelligence for compliance, one of the hardest and most complex untapped challenges in the field. To tackle this, Lettria uses a unique graph-based text-to-graph generation model that is 30% more accurate and runs 400x faster than popular LLMs for parsing complex, multimodal compliance documents. It preserves document layout features like tables and diagrams as well as semantic relationships, enabling precise extraction and understanding of compliance content.
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