A plugin is a package that bundles several pieces for an AI assistant, like skills, connectors, commands and agents, and installs in one go. It lets a whole team work with the same setup, without each person building their own. It exists in Claude Code and in other tools.
A question from the app. Pick an answer.
Description: "Helps with orders and prices." It loads on price edits. How to narrow it?
The instructions are read after it is picked. To avoid picking it, they come too late.
The description is what the agent compares with the task. If it says "only for exporting," editing prices no longer fits.
A script does the work the same way every time, but it does not decide when the skill gets picked.
A plugin is a box of pieces that already existed separately: skills (recipes for tasks), connectors to your tools, agents to delegate to and settings that run at certain moments, like after editing a file. The plugin invents nothing new: it packages them.
Founder example: a "sales" plugin with a skill for drafting proposals, a connector to your CRM and an agent that prepares Monday's meeting. You install it once and all three pieces arrive together. Connectors are still authorized one by one.
So a team does not build the same setup five times, each one different. Someone prepares it, publishes it in a catalog (in Claude Code it is called a marketplace) and the others install it with one command and get the updates. Everything in it also works loose, without a plugin; the plugin just saves the work of handing it out.
The same format also installs on claude.ai and in Cowork, though a different set of components loads there. Other AI tools have similar packages, with other names and rules: check what it is called and what it supports in the one you use.
A plugin can run code, and what it runs it runs with your permissions, as if you did it yourself. Install only from sources you know and look at what it holds. And mind the cost: skills the assistant can pick on its own take up space in every conversation, even if you do not use them, which uses your quota. Installing twenty "just in case" is not free.