Overview
This step-by-step guide explains how to use the Document Analyst feature in CustomGPT.ai, which enables advanced document-based reasoning for your agents.
What is the Document Analyst feature?
Document Analyst is an advanced agentic feature that allows your agent to analyze documents uploaded by end users. It combines the contents of an uploaded document with the agentβs existing knowledge base to deliver richer, more contextual answers - ideal for discussing reports, contracts, or any detailed reference material.
When enabled, users can upload a PDF document during their conversation. This mode activates multiple reasoning steps, making it more powerful for understanding and responding to user-provided data.

Overview of the feature
- You will see an attachment icon next to the chat input field to upload a document (see this guide to enable Document Analyst).
- Uploaded documents are available only within the active chat session.
- The agent analyzes the document alongside its knowledge base to generate richer, more accurate responses (learn more about Document Analyst best practices).
- One document analysis consumes the equivalent of ten standard queries due to advanced multi-step reasoning (learn more about Action Costs and Usage Tracking).
- Supported file type: PDF only (other formats are not supported yet)
- Maximum file size: 5 MB (split large documents into smaller sections if needed).
- Maximum word length: 3,000 words (longer content is truncated)
- Only one document can be analyzed per session; if multiple are uploaded, the latest is used
- Limits will expand as the feature evolves
How it works
- Users will see an attachment icon next to the chat input field.
- They can upload a document (PDF) directly within the chat.
- Once uploaded, the document is available only for that chat session and not stored permanently.
- The agent performs multi-step reasoning, combining its knowledge base with your documentβs content.
Note:Document Analyst is an advanced feature that involves multiple reasoning steps. Each analysis counts as 10 queries in your usage which may significantly impact your usage costs. Review the action costs before proceeding.
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Updated 5 days ago