Workflows are used in industry to organize LLM applications. Existing workflow representations are not well suited for LLM-based generation and reasoning. In this paper, we define requirements for an LLM-oriented workflow language. We propose SysML v2 action flows as a language satisfying these requirements. To support quantitative research in this direction, we build a public dataset of nearly 75k SysML v2 action flows by transforming existing datasets of workflow graphs, BPMN models, and standard operating procedures. The resulting dataset covers workflows with diverse complexity, providing a useful basis for future work on workflow analysis and generation with LLMs.