Agent skills are markdown files with a little frontmatter, and three different kinds of place now distribute them:
- skills.sh, a registry and leaderboard run by Vercel
- agenticskills.io, an independent curated directory
- Host-native marketplaces, like Claude Code’s plugin marketplace and OpenClaw’s ClawHub
The differences are worth mapping, because the unit being distributed is identical in all three.
The registry: skills.sh
skills.sh treats a GitHub repo as the unit. npx skills add <owner/repo> pulls a skill set straight from its repository and writes editable files into your project; the site itself is an index and install counter over repos it does not host. Skill sets from Anthropic, Microsoft, Vercel Labs, and individual authors sit in one namespace, browsable by topic, and the leaderboard ranks by installs.
The design bet is that GitHub already solved hosting, versioning, and trust, so the registry only needs to solve discovery. That keeps the barrier to publishing at “push a repo”, which is why so many single-author skill sets are listed.
The curated directory: agenticskills.io
agenticskills.io is editorial where skills.sh is algorithmic. Skills are hand-sorted into sixteen categories, given featured picks and a popularity rank, and listed alongside MCP servers, which the registry does not touch. It is explicitly independent, unaffiliated with any platform vendor.
Indexing skills and MCP servers side by side sets it apart. They are different layers (behaviour versus tools), but a developer setting up an agent shops for both at once, and this is the only place that treats them as one catalogue.
The host marketplaces
Claude Code’s plugin marketplace and ClawHub both distribute skills for one host, with the host’s own install, update, and permission story. What you gain is management: a marketplace plugin can be read-only and auto-updating rather than files you own and edit. What you lose is reach, since the listing works in one runtime.
What the map says
All three shapes move the same artefact: a SKILL.md file an agent reads. Nothing in the file binds it to a host, which is why one repo can appear in the registry, the directory, and a marketplace simultaneously, and why the cross-host installers can write the same files into ~/.claude/skills/, ~/.codex/skills/, or .cursor/skills/ without translation.
That makes skills the loosest, most portable layer of agent customisation. These sites compete on discovery and trust, the same ground package registries fought over a decade ago, minus the build step.