SubPilot: An AI Assistant for Smart Contract and Subscription Management

SubPilot is a full-stack web application positioned as "your AI co-pilot for subscriptions and contracts". It aims to help users centrally manage recurring contracts and subscriptions, track expenses, keep track of deadlines, and use AI to generate professional cancellation letter drafts. It integrates contract tracking, expense analysis, deadline reminders, and AI-assisted cancellation features to address pain points in the subscription economy, while emphasizing privacy protection and open-source characteristics.

In the digital age, users often subscribe to dozens of services (streaming, cloud storage, SaaS, etc.) with automatic renewal, making it easy to forget subscription details, deduction times, and expiration dates. Canceling services involves tedious processes and requires writing formal emails, which deters users. SubPilot is an AI-driven contract management tool designed to solve these pain points.

1. Unified Contract Dashboard: Centrally manage all subscription and contract statuses, eliminating the need to switch between multiple platforms;
2. Expense Tracking and Visual Analysis: Automatically monitor recurring expenses, display composition and category distribution via charts to assist financial decision-making;
3. Smart Deadline Management: Track renewal and cancellation deadlines, send reminders at key points to avoid forgetting to cancel deductions;
4. AI-Driven Cancellation Letter Generation: Generate professional drafts with basic information provided, privacy-first design (separation of sensitive data from AI layer), and users can preview and approve before sending;
5. Activity Tracking and Auditing: Record all contract changes to form a complete log, suitable for enterprise team account management.

Backend: Built with Python + FastAPI for REST APIs, SQLAlchemy as the ORM layer, and SQLite for the development environment; Frontend: Uses React + TypeScript to ensure type safety, Vite as the build tool, TailwindCSS for UI design, and Framer Motion for animations; AI Integration: Generates cancellation letters based on large language models, uses structured prompts to ensure output quality, and employs privacy-aware design to separate sensitive data from the AI layer.

SubPilot places privacy protection at its core: The AI layer only processes general templates and does not access sensitive information; sensitive data is processed locally on the backend; users must review and approve all content before sending; the optional inbox subscription detection feature is enabled at the user's discretion. This design embodies the concept of AI as an auxiliary tool rather than a black-box decision-maker.

Future evolution directions include: AI-driven expense insight analysis, inbox-based automatic subscription detection, budget tracking and overspending alerts, and multi-language contract workflow support.

SubPilot represents a new paradigm for AI applications: embedding into specific workflows to handle tedious standardized tasks (such as writing cancellation letters) while keeping humans in control of key decisions. For ordinary users, it solves subscription management pain points; for developers, it demonstrates how to integrate large language models under privacy constraints. The "AI assistance + human review" hybrid model is one of the best practices for current AI implementation.