Climate services are increasingly recognized as important tools for supporting climate change adaptation by providing timely, relevant, and actionable climate information for decision-making. However, limited attention has been given to how climate services are conceptualized and recognized within the communities involved in researching, developing, and using them. In this paper, we investigate whether what is recognized as a climate service is shaped more by its purpose (the needs it addresses) and function (the processes through which it supports decision-making), or by its form (the way it is delivered, such as digital platforms or non-digital tools). Drawing on Rasmussen's Abstraction Hierarchy, we first analyze widely used definitions of climate services to examine how purpose, function, and form are embedded in formal conceptualizations. We then use this analysis to design a survey of researchers, developers/providers, and practitioners involved in European climate-service initiatives. The results show that widely used definitions emphasize purpose and function more than form. However, survey respondents were substantially more likely to recognize digital and data-driven tools as climate services than unconventional formats, even when the latter fulfilled similar functions. While recognition patterns were broadly consistent across disciplinary and professional backgrounds, the findings suggest that shared institutional expectations may shape what is considered a legitimate climate service. These findings point to the need to question implicit biases during the development and implementation of climate services and hint at the limits of interdisciplinarity alone in addressing the “usability gap”. Instead, we argue for the potential value of broader transdisciplinary and co-creative approaches that incorporate diverse actors, forms of expertise, and ways of delivering climate-related knowledge. Overall, the study provides an empirical basis for reflecting on how expectations about service form may influence the boundaries and future development of the climate services field. Form over Function: How design expectations shape what counts as a climate service