xby-biomarker-ranges: A Biological Age Calculation Plugin Based on the PhenoAge Model

`xby-biomarker-ranges` is a DeepSeek Harness (DSH) plugin based on Morgan Levine's PhenoAge model, designed to provide agents with biological age calculation and biomarker reference range lookups. Users can persistently configure their API key using `set_xby_apikey` and analyze blood data with commands such as `calculate_phenoage` and `get_biomarker_ranges`. The plugin supports local debugging and is suitable for agent applications that require integrating biological data analysis, but it should be run in a controlled environment and require a valid API key.