Modelator 2: Judgment day for manual modeling

"Modelator 2: Judgment day for manual modeling," presented by Stéphane Begaudeau (Obeo), demonstrates how large language models are integrated into web-based modelling tools to support system design, editing, and automation. This session is part of the Open Community for AI at Open Community Experience 2026 in Brussels, Belgium. This session presents ongoing work to integrate AI capabilities into the Sirius Web modelling ecosystem. The goal is to augment modelling tools with LLM-based assistants while remaining compatible with multiple models and deployment environments. Two integration approaches are explored. In the first, Sirius Web acts as an internal AI agent embedded in the application. It uses contextual data from the modelling environment such as diagrams, selections, and semantic models to assist with tasks like querying, editing, and generating architecture elements. In the second approach, Sirius Web exposes functionality through MCP APIs, allowing external agents to interact with models. This enables broader workflows where modelling tools become part of a larger agent ecosystem, with controlled access based on user permissions. The session demonstrates how AI can generate and modify system architectures using domain-specific concepts, moving from low-level model representations to domain-relevant abstractions such as components and functions. Customisation is achieved through configurable prompts, tools, and domain-specific extensions. Key topics covered - sirius web modelling platform - llm integration in modelling tools - ai agents for system modelling - internal vs external agent architectures - multi-agent workflows in modelling - access control and permissions in ai systems Why this matters Integrating AI into modelling tools changes how system architectures are created and maintained. Understanding how these systems operate within controlled environments is important for ensuring correctness, traceability, and integration with existing engineering workflows. About OCX26 Open Community Experience 2026 is the Eclipse Foundation’s flagship event, held in Brussels, Belgium. It brings together developers, architects, and industry leaders to explore open source technologies across domains including AI, automotive, tooling, and cloud systems, with a focus on practical implementation. Learn more at https://www.ocxconf.org/ Chapters 00:00 introduction and goals 00:29 integrating ai into sirius web 01:18 compatibility with multiple llms 01:45 experimentation and use case development 02:27 internal ai agent architecture 03:11 chat interface and prompt control 03:48 integration with modelling context 04:36 querying and navigating model data 05:26 semantic vs graphical model access 06:01 customising prompts and domain context 06:48 domain abstraction (uml, sysml, arcadia) 07:32 mapping to system engineering concepts 08:03 generating system architectures 09:02 planning and execution workflows 09:48 batch updates and automation 10:25 token optimisation and performance 10:32 external agents via mcp api 10:59 multi-project and cross-context workflows 11:44 collaboration and ecosystem integration 12:00 roadmap: undo/redo and ux improvements 13:31 authentication and mcp extensions