Langsmith Cowriter is an AI writing tool designed to make the entire writing process more efficient, from early planning to final review. It supports a wide range of content, including blog articles, press releases, proposals, reports, social media posts, emails, white papers, and other business documents. Rather than focusing only on generating text, the service helps users reduce the time spent organizing ideas, checking content, and making revisions.

Writers can use chat to clarify their audience, purpose, and key points, then develop an outline, organize information in notes, and generate a draft. Suggestions and rewriting tools help improve selected passages or identify areas for broader revision, while review features support consistency and fact-checking. Web search, adjustable tone and length settings, and the ability to ask questions are also included.

Langsmith Cowriter offers a seven-day trial with access to its features, followed by a single plan priced at ¥1,500 per month.