What Is LangSmith Prompt Hub and How to Use It to Create, Version, and Share Prompts

LangSmith Prompt Hub is a system within LangSmith for creating, versioning, tagging, testing, and sharing prompt templates for LLM applications. It supports two template formats (f-string and mustache), a Playground for testing, commit-based versioning with movable tags for staging/production environments, and SDK-based push/pull workflows. The post covers the full workflow: building prompts, testing in Playground, saving commits, tagging versions, pulling tagged prompts into app code, and using the public community hub. It also addresses common issues like deprecated langchainhub package migration, variable rendering problems, caching behavior, and safety considerations for public prompts.