cometCOS is a multi-tenant content operating system designed for writers, publishers, and content teams who need an integrated environment for drafting, editing, versioning, and publishing. It functions as a writing studio that incorporates AI assistance, allowing users to generate drafts from their own OpenAI or Claude API keys, edit in a rich text editor, and publish to platforms such as WordPress, Ghost, Medium, LinkedIn, and Buffer. The system emphasizes keeping the writer in control: AI suggestions are presented for review before being accepted, and every version of a document is saved and accessible so previous iterations can be restored. Key features include per-client workspaces with separate voice, team, keys, and publishing settings; team roles that distinguish writers, editors, and approvers; an AI cost HUD that displays token usage by post, writer, and client; and a bring your own key (BYOK) model that keeps provider costs transparent. The platform supports portable open formats, allowing writers to export and retain ownership of their work. It is intended for individual writers, blog owners, ebook or long-form authors, and content agencies or studios. A typical workflow begins with pasting an idea, generating a draft in the user’s own voice using their own AI key, then editing and refining in the built-in rich text editor. Users can highlight a paragraph and ask the AI to tighten it, accept or reject the suggestion, and iterate through versions. Once finalized, content can be published to one or multiple destinations directly from the studio. The system aims to consolidate what often requires multiple tabs and tools into a single workspace, reducing context switching and providing visibility into content performance and AI costs.