Architectures for Agent Systems: A Survey of Isolation, Integration, and Governance
Large Language Model (LLM) based agent systems – software that leverages LLMs to autonomously plan and execute multi-step tasks using external tools – are rapidly moving from proof-of-concept demos into enterprise deployment. These agents promise to automate coding, IT operations, data analysis, and more, but deploying them in production raises new challenges in security, reliability, and integration. Over the last half-year, the community has converged on key strategies: strong isolation for executing untrusted actions, standardized protocols for tool integration, and governance frameworks to align agent behavior with enterprise policies. This survey provides a systematic review of recent developments (roughly the latter half of 2025), including agent sandbox architectures, emerging standards like MCP, open-source projects, industry initiatives, and research advances. We focus on the pain points encountered when bringing agent systems to production and how the latest solutions address (or still fall short on) those needs.