Compare
The things people mix up
Four pairs that get confused constantly. Each one written from actually using both, not from the docs.
Plugins vs skills
One runs code inside your session. One is text the model reads.
Mods vs MCP servers
Both add capability. Only one runs in your terminal.
Being written
Mods vs slash commands
A command you type. A thing that runs when you did not type it.
Being written
Claude Code mods vs Codex mods
Same idea, different host, different failure modes.
Being written