Use a Skill when a task needs a repeatable method, supporting files or project-specific instructions. It complements the request; it does not replace saying what result you want now.
Work with an installed Skill
Open Settings → Skills. Select a Skill to inspect its description, instructions and supporting files. User-created entries can be edited; built-in entries are read-only. When creating one, choose the location and whether it belongs to the user or the project.
In a project conversation, type @ and choose the Skill from the mention list. Add the task and send. / is the command picker, not a second Skill palette.
Find a procedure someone else published
On desktop or Web, Settings → Skills Catalog is a separate settings page. Select a source, search, inspect an entry and choose its installation location. Add catalog accepts another source.
The dedicated phone Settings navigation does not expose Skills Catalog. Install from a supported interface, then return to the installed Skills page on the host you use.
For tool connections rather than instructions, configure MCP.