Summarist.ai: AI-Powered PDF Summarization Platform

Overview

Summarist.ai is a modern AI-powered application that transforms PDF documents into clear, structured, and visually engaging summaries. Built with Next.js and powered by Google Gemini AI, the platform allows users to upload PDFs, receive AI-generated summaries with emoji-enhanced formatting, manage their summaries in a personalized dashboard, and export them as markdown files.

What Users Can Do

• Upload PDFs: Drag and drop or click to upload PDF documents (up to 20MB)
• AI Summarization: Get instant AI-generated summaries using Google Gemini 2.5 Flash model
• Interactive Viewer: Navigate through summaries with a beautiful, section-based viewer with progress tracking
• Dashboard Management: Access and manage all your summaries in one place
• Download Summaries: Export summaries as markdown/text files for offline use
• Subscription Plans: Choose between Basic (5 summaries/month) or Pro (unlimited summaries) plans
• Progress Tracking: Visual progress bar showing reading progress through summary sections
• Beautiful UI: Modern, responsive design with smooth animations and gradients

Why I Built This

I built Summarist.ai to solve several key problems I faced while working with lengthy PDF documents:

• Time Consumption: Reading long PDFs takes too much time, especially for research papers, reports, and documentation
• Information Overload: Extracting key insights from dense documents is challenging
• Lack of Structure: PDFs often lack clear structure, making it hard to quickly find important information
• No Quick Summaries: Existing tools don't provide engaging, well-formatted summaries with visual elements
• Export Limitations: Need to easily save and share summaries in a portable format

Tech Stack

Frontend

• Next.js 15.2.2 - React framework with App Router
• React 19 - UI library
• TypeScript - Type safety
• Tailwind CSS 4 - Utility-first CSS framework
• Shadcn UI - Component library
• Framer Motion - Animation library
• Lucide React - Icon library

Backend & Services

• Google Gemini AI - AI model for summary generation (Gemini 2.5 Flash)
• LangChain - PDF text extraction and processing
• NeonDB - Serverless PostgreSQL database
• Clerk - Authentication and user management
• UploadThing - File upload service
• Stripe - Payment processing and subscription management

Development Tools

• Zod - Schema validation
• Sonner - Toast notifications
• date-fns - Date formatting utilities

Key Features

1. AI-Powered Summarization

• Uses Google Gemini 2.5 Flash model for fast, accurate summaries
• Structured prompt engineering for consistent output format
• Emoji-enhanced summaries for better readability
• Markdown formatting with proper sections and hierarchy

2. PDF Processing Pipeline

• LangChain PDFLoader for text extraction
• Handles multi-page documents seamlessly
• Error handling for corrupted or unreadable PDFs
• File size validation (20MB limit)

3. Interactive Summary Viewer

• Section-based navigation with smooth transitions
• Progress bar showing reading completion
• Sticky section headers for context
• Responsive design for all screen sizes
• Beautiful gradient backgrounds and animations

4. User Dashboard

• View all summaries in a grid layout
• Empty state with helpful messaging
• Upload limit tracking and upgrade prompts
• Quick access to create new summaries
• Summary cards with metadata (title, creation date)

5. Subscription Management

• Two-tier pricing: Basic ($7/month) and Pro ($15/month)
• Stripe integration for secure payments
• Automatic subscription status tracking
• Upload limit enforcement based on plan
• Seamless upgrade flow

6. File Management

• Secure file uploads via UploadThing
• Original PDF storage and retrieval
• Summary text storage in database
• Download functionality for summaries

Technical Implementation

Summary Generation Flow

1. User uploads PDF via UploadThing
2. Server action extracts text using LangChain PDFLoader
3. Text is sent to Google Gemini AI with structured prompt
4. AI generates formatted summary with emojis and markdown
5. Summary is saved to NeonDB with user association
6. User is redirected to summary viewer page

Database Schema

• pdf_summaries table: Stores summaries with user_id, file_url, summary_text, title, file_name
• users table: Manages user subscriptions with customer_id, price_id, status
• payments table: Tracks payment transactions

Authentication & Authorization

• Clerk handles user authentication
• Protected routes for dashboard and upload pages
• Server-side user validation for all actions
• Secure API routes for payment webhooks

After Launch & Impact

• Built a complete full-stack AI application from scratch
• Integrated multiple third-party services (Clerk, Stripe, UploadThing, Gemini)
• Learned advanced prompt engineering for consistent AI outputs
• Implemented subscription-based monetization model
• Created beautiful, responsive UI with modern animations
• Gained experience with serverless database architecture
• Learned file upload handling and PDF processing
• Implemented real-time feedback during processing

Challenges Overcome

1. PDF Text Extraction: Implemented robust PDF parsing using LangChain to handle various PDF formats and structures
2. AI Prompt Engineering: Created structured prompts to ensure consistent, well-formatted summaries with emojis
3. File Upload Handling: Integrated UploadThing for secure, scalable file storage
4. Payment Integration: Set up Stripe webhooks for subscription management and payment tracking
5. Real-time Feedback: Implemented toast notifications and loading states for better UX
6. Summary Formatting: Parsed markdown summaries into interactive sections with navigation
7. Database Design: Designed efficient schema for storing summaries and user data
8. Subscription Limits: Implemented upload limit tracking and enforcement based on user plans

Future Plans

• Add support for more file formats (DOCX, TXT, etc.)
• Implement summary sharing functionality
• Add summary editing capabilities
• Create summary templates for different document types
• Add batch processing for multiple PDFs
• Implement summary search and filtering
• Add export to PDF format
• Create API for third-party integrations
• Add team collaboration features
• Implement advanced analytics for summary insights