Abstract: With the continuous deepening of digital transformation in water conservancy, traditional water conservancy business systems are facing problems such as process solidification, difficulty in coordinating model resources, and insufficient integration of domain knowledge, which are difficult to meet the intelligent analysis and decision-making needs in complex business scenarios. To address the above issues, a research and development approach for water conservancy business intelligent agents(Agents) based on task orchestration and engine assembly is proposed. With business tasks as the core, complex business processes are structured and organized through task modeling and orchestration. The engine assembly mechanism is used to dynamically combine large language models, domain knowledge, water conservancy professional models, business tools, and existing intelligent service capabilities. Combined with dynamic scheduling and multi-agent collaboration mechanisms, different intelligent service capabilities are collaboratively executed around business goals. This method improves the organizational efficiency and reusability of models, knowledge, and tool resources in intelligent applications of water conservancy business,providing a technical path for the rapid construction and application of intelligent agents in complex water conservancy scenarios.