The growing complexity and variety of Internet of Things (IoT) environments create significant challenges for keeping high-quality documentation throughout the Software Development Life Cycle (SDLC). This paper introduces a Multi-Agent System (MAS) architecture designed to automate documentation tasks across all phases of the SDLC, reducing manual effort and improving traceability. Outdated documentation methods, especially in distributed IoT systems, face hurdles due to constant changes, dynamically evolving requirements, and diverse stakeholder demands, resulting in an incessant need for updates, which makes traditional manual documentation unfeasible. The topic of this paper is to propose a novel architecture for Multi-Agent Systems (MAS) to formalize the automation of documentation development and updates throughout the SDLC stages in IoT system environments. The system proposed in this paper leverages the autonomous, cooperative, and specialized nature of MAS to assign the responsibility of generating structured documentation throughout SDLC stages to individual agents operating within coordinated processes. Every agent operates on domain-specific knowledge that includes task-related data and logic in accordance with its role, but they share a common memory system as a whole for coordination and data sharing. This allows for the production of verifiable, consistent, and traceable documents that are uniform but differ in granular detail across development phases. A detailed scenario of smart home development illustrates system effectiveness and practicality within real-world IoT environments while showcasing the initial simulations performed in controlled environments that demonstrate significant promise.