Salesforce's Voice and Tone Guidelines (part of the Lightning Design System) cover writing standards for in-app text, error messages, help documentation, developer docs and Trailhead learning content, a practical intro to applying Salesforce's distinct voice consistently.
Free: part of the public Lightning Design System documentation.
Content designers wanting a real, large-scale enterprise example of voice-and-tone guidelines applied consistently across product UI, documentation and learning content.
Useful specifically as a reference for how one company applies a single documented voice across very different content types (error messages vs. learning modules), a good model for teams facing the same consistency challenge.
Voice and tone guidelines from the Salesforce Lightning Design System.
