Developing sophisticated AI agents often brings to mind complex frameworks and extensive libraries. However, the HNG Stage 3 Backend task challenged this notion, leading to the creation of a powerful License Compatibility Checker Agent for Telex.im, built entirely from scratch using pure Java 17+. This agent is not just another Q&A bot; it’s a dedicated tool for developers, offering on-demand license checks, detailed insights, and proactive educational content, all without relying on heavyweight frameworks like Spring.

Architectural Elegance in Java

To ensure a clean, maintainable, and highly testable codebase, the agent adopts a straightforward Layered Architecture. Inspired by the classic Model-View-Controller (MVC) pattern, it replaces the “View” with a dedicated formatting layer. This design principle emphasizes the separation of concerns, with distinct classes handling specific tasks:
* Main: Manages server setup, thread pooling, and endpoint registration.
* Controllers: Process incoming HTTP requests and translate them into service calls.
* Services: House the core business logic, including caching, API interactions, scheduling, and the crucial compatibility matrix.
* Utilities: Provide shared helper functions for HTTP communication, JSON parsing, natural language processing (NLP), and Markdown formatting.
* Models: Simple POJOs (Plain Old Java Objects) for seamless data transfer.

This structured approach prevents code bloat and enhances clarity, allowing components like MessageProcessor and LicenseExtractor to work synergistically, from parsing complex natural language queries to formatting the final Markdown response.

Core Logic and Smart Features

The agent’s intelligence is powered by several key functionalities:

1. Data Sourcing and Intelligent Caching: The GitHub Licenses API serves as the primary, free data source. To optimize performance and conserve bandwidth, the LicenseService implements an efficient in-memory HashMap cache. Once a license’s details are fetched from GitHub, they are stored and instantly retrieved for all subsequent requests, ensuring rapid responses.

2. The “Clock System” for Proactive Insights: A standout feature is its proactive content delivery. The SchedulerService leverages Java’s ScheduledExecutorService to run a task every 24 hours. This task intelligently determines the “License of the Day” based on the day of the year, ensuring fresh content daily, and then posts this educational insight to a designated channel via an internal messaging mechanism.

3. Robust Compatibility Logic: At its heart, the LicenseService contains a meticulously pre-computed compatibility matrix. This matrix is based on established open-source license guidelines, such as GPL’s Copyleft requirements, enabling accurate and instantaneous answers to complex queries like, “Can I use MIT with GPL-3.0?”

Seamless Integration with Telex.im

Integration with the Telex.im platform was achieved by adhering strictly to the Agent-to-Agent (A2A) JSON-RPC 2.0 standard, exposed through three main public HTTP endpoints:

1. Agent Card Discovery (/.well-known/agent-card): This initial handshake endpoint serves a static agent-card.json file, clearly detailing the agent’s capabilities (e.g., license-compatibility-check, daily-license-insights) and available skills.

2. Message Handling (/v1/message): This is the primary interaction point. The MessageController receives JSON-RPC requests, extracts the user’s plain text message, and then delegates to the MessageProcessor to determine the user’s intent (compatibility check, info request, or list request), finally returning a valid JSON-RPC result object with the Markdown-formatted response.

3. Health Check (/health): A simple endpoint for platform monitoring, ensuring the agent server is operational and responsive.

This pure Java AI agent exemplifies how robust, high-performance, and feature-rich applications can be built without external frameworks, offering a tailored and efficient solution for license compatibility within the Telex.im ecosystem.