Developer packages marketing Skills for Claude, ChatGPT and Codex

On October 25, 2026, a developer published a write-up on DEV Community about packaging marketing Skills so they can be installed in Claude, ChatGPT, and Codex at the same time. The author shipped 11 marketing Skills as the companion pack to a free handbook written in Chinese, AI Digital Marketing in Practice (1,100+ pages). Its readers use Claude, ChatGPT, and Codex, and the book never asks them to open a terminal. The piece notes that Claude and Codex now both have a skills folder, and neither one reads the other's. Because the two tools keep separate skills directories, the author had to build three kinds of ZIP from a single source folder, with an install path in all three tools that never touches a shell. Five things broke along the way, including an inconsistency in the character limit for Skill descriptions: an open standard allows 1,024 characters, while Claude's help center lists only 200. To verify that the Skills actually get triggered, the author provides a validation script and headless tests. No further developments are reported in the available material.