TermSheet Analysis Tool (Azure OpenAI & Google Gemini)

Disclaimer: This tool performs an analysis of legal documents. It does not provide legal advice, and its use does not establish an attorney-client relationship or attorney-client privilege. If you require attorney-client privilege or legal counsel, please consult with a qualified attorney. The results generated by this should not be relied upon as a substitute for professional legal advice.

This tool automates the analysis of legal contracts (PDF, Word, Excel, Images) using Large Language Models (LLMs). It supports Azure OpenAI (GPT-4) and Google Gemini (2.0 Flash), allowing for flexible, high-capacity document review.

Key Features

• Hybrid Provider Support: Switch between Azure OpenAI and Google Gemini.
• Dynamic Context Window: Automatically adjusts analysis chunk sizes based on the selected model's capacity (maximizing "Vik's Law" of 20-30% utilization).
• Multi-Format Support: Extracts text from PDFs (OCR enabled), Word docs (.docx, .doc), Excel files (.xlsx), and common image formats.
• Excel Reporting: Generates a structured Excel report (ai_results.xlsx) with analysis results for each contract.
• GUI & CLI: Modern, user-friendly graphical interface and robust command-line interface.

1. Prerequisites

• Python 3.10+ (Recommended)
• Tesseract OCR (for scanned PDFs/Images)
  • Windows: Install from UB-Mannheim/tesseract and ensure tesseract.exe is in your system PATH.
• Poppler (for PDF processing)
  • Windows: Download from poppler-windows, extract, and add the bin folder to your system PATH.

2. Dependencies

Install the required Python packages:

pip install -r requirements.txt

3. Configuration

Environment Variables (Authentication)

Create a .env file or set these variables in your system:

For Azure OpenAI:

• AZURE_OPENAI_API_KEY: (Optional) If using API Key auth. If not set, the tool attempts Azure AD authentication (CLI, VS Code, Browser).

For Google Gemini:

• API Key: Set GOOGLE_API_KEY environment variable.
• OAuth (Recommended): Download client_secret.json from Google Cloud Console.
  • Create a Project > APIs & Services > Credentials.
  • Create "OAuth 2.0 Client ID" (Desktop App).
  • Download the JSON file and save it (e.g., as client_secret.json).

Prompts

• The tool uses LOI_prompts.yaml (formerly prompts.yaml) to define the analysis questions.
• Format:

  prompts:
    - column_header: "Parties Involved"
      prompt: "Identify the buyer and seller in this contract."
    - column_header: "Effective Date"
      prompt: "What is the effective date of the agreement?"

4. Usage

Graphical Interface (GUI)

Simply run the script without arguments to launch the GUI:

python LOI_Analysis.py

• Select Input: Local folder or file.
• Provider: Choose between Google (Gemini 2.0 Flash - Default) and Azure (GPT-4o).
• Auth Method:
  • Google: OAuth (Recommended), API Key, or ADC.
  • Azure: RBAC or API Key.

Command Line Interface (CLI)

Run headlessly for automation:

# Analyze a folder using Google Gemini (Default)
python LOI_Analysis.py --input "C:\Contracts" --output "ai_results.xlsx"

# Analyze using Azure OpenAI
python LOI_Analysis.py --input "C:\Contracts" --provider azure

# Specify a specific model
python LOI_Analysis.py --input "C:\Contracts" --provider google --model gemini-2.0-flash-001

5. Context Window Logic ("Vik's Law")

The tool dynamically calculates the safe amount of text to send based on the model:

• GPT-4o: ~128k tokens context -> Process ~30k tokens (~100k chars) per chunk.
• Gemini 2.0 Flash: ~1M tokens context -> Process huge documents in single pass.

6. Project Structure

• LOI_Analysis.py: Main application logic.
• auth.py: Authentication handlers for Azure and Google.
• LOI_prompts.yaml: Analysis questions configuration.
• requirements.txt: Python dependencies.
• Contracts/: Default input directory.

7. Building the Executable

You can create a standalone executable of the application using PyInstaller.

1. Install PyInstaller:

   pip install pyinstaller

2. Build the Executable:

   pyinstaller --onefile LOI_Analysis.py

   This command will generate a single executable file in the dist folder.

Troubleshooting

• Tesseract Not Found: Ensure Tesseract is installed and added to PATH. You may need to restart your terminal/IDE.
• Azure Auth Errors: Try running az login in your terminal if using RBAC.
• Google Auth Errors: Ensure GOOGLE_API_KEY is set correctly.
• PDF Extraction Issues: If OCR fails, check the logs for Poppler/Tesseract errors.