How to Sync AI Coding Agent Skills Across Every Platform: One Repo, Zero Copy-Paste

The Multi-Agent Skill Fragmentation Problem If you use more than one AI coding agent in 2026, you've almost certainly encountered this: you refine a skill in Claude Code, then realize Codex doesn't have it. You copy it over. Then you update the original. Now Codex is stale. Then you remember Perplexity Computer needs it too, but that requires uploading through a web dashboard. Multiply this by 20+ skills across 5 platforms and you've built yourself a maintenance nightmare that feels eerily similar to the pre-package-manager era of vendoring dependencies. This isn't a hypothetical pain point. Developer forums and communities are full of threads describing exactly this workflow breakdown. The root cause is structural: each AI coding agent stores skills in a different location, using different formats, and some platforms (Claude Desktop, Perplexity Computer) don't even have local file access — they require browser-based uploads to cloud dashboards. The common workarounds developers reach