This repository implements the Azure Pipelines Agent, a cross-platform CI/CD agent that executes build, release, and deployment jobs for Azure DevOps and Team Foundation Server. The agent is written in C# on .NET Core and runs on Windows, macOS, and Linux. Its architecture consists of a Listener process that handles agent lifecycle (registration, authentication, message polling) and a Worker process that executes job steps (tasks, scripts, containers). The codebase includes a plugin system for source control (Git, TFVC, SVN), artifact management, pipeline caching, test result publishing, and code coverage. It features a robust configuration system based on knobs, secret masking, telemetry, and extensive logging. The agent communicates with Azure DevOps services via REST APIs and manages credential storage, proxies, and certificates. While the codebase is mature and well-structured, it contains some legacy code paths, platform-specific implementations, and feature flag complexity that reflect its long evolution.