Mail classification using AI waterfall

email_classification_ai_waterfall.py

import re

def classify_email_basic(email_content, subject):
    # Support tickets
    if re.search(r'\b(help|support|issue|problem|bug|error)\b', subject.lower()):
        return 'support'
    
    # Sales inquiries
    if re.search(r'\b(quote|pricing|purchase|buy|demo)\b', subject.lower()):
        return 'sales'
    
    # HR/Recruitment
    if re.search(r'\b(job|career|interview|resume|hiring)\b', subject.lower()):
        return 'hr'
    
    # If no pattern matches, escalate to LLM
    client = OpenAI(api_key=API_KEY)
    prompt = 
    f"""
    Classify the following email into one of the following categories
    1. Support - For support tickets and issues
    2. Sales - For sales inquiries, pricing etc.
    3. HR - For recruitment inquiries, interviews scheduling etc.
    
    {subject} {email_content}
    """
    llm_classification = client.responses.create(model='gpt-4.1', input=prompt).output_tex
    return llm_classification