Object-Oriented Models(OOM)are widely used in Model-Driven Engineering(MDE).As a complement, OCL constraints are used to specify business rules and detailed aspects of the business domain. Automatically co-evolving OCL constraints w.r.t. the evolved OOM is challenging since alternative resolutions can be applied but also a resolution cannot be applied to any arbitrary constraint. In this paper, we present SAC-OCL an Eclipse-based tool to semi automatically co-evolve OCL constraints when an OOM evolves. In contrast to existing tools, SAC-OCL proposes alternative resolutions for an impacted OCL constraint and proposes only the appropriate resolutions that can be applied on the impacted constraint. Our evaluation on six case studies shows an average correct co-evolution rate of 92%