Skills and plugins

By the end, you will distinguish a Skill, Plugin and Connector using a course-update review. Outputs are illustrations, not proof of installation.

A Skill teaches a repeatable workflow. A Plugin packages capabilities such as skills, connectors, agents and hooks. An MCP Connector supplies tools and external access. A Skill saying “read the calendar” does not create a calendar connection.

Sources checked on September 30, 2026 describe product- and plan-specific installation. Plugins are documented for Cowork and Code, not Chat in the inspected installation guide. New-interface rollout can change entry points.

Review my update draft using this process:
1. Separate facts, proposals and missing details.
2. Identify claims unsupported by the source.
3. Return a corrected draft and change list.
Do not send, share or connect another service.
If no source is supplied, request it rather than approving the draft.

If useful across repeated tasks, the process may merit a Skill. One-off work may only need chat instructions. Not every preference needs a Plugin.

Example personal-practice SKILL.md:

---
name: course-update-check
description: Check a course update against its supplied source before reuse.
---
# Course update check
Use only the source and draft the user supplied.
Separate facts, proposals and missing information.
List unsupported claims. Return a corrected draft and a change list.
Do not send, publish, connect accounts or invent missing facts.
If no source was supplied, ask for it.

Use a clear name, description and testable process. Keep secrets and temporary data out. Claude and Claude Code install Skills differently; follow your product's mechanism. A file in an arbitrary folder is not necessarily active. Without installation support, use the process in chat without claiming it is installed.

Source: Chapter 1 ready. Chapter 2 under review. Date unset.
Draft: All chapters are ready and publication is on Sunday.
Use the course-update review process.

Illustrative correct output:

Unsupported: all chapters ready; Sunday publication.
Corrected: Chapter 1 is ready, Chapter 2 remains under review and no date is set.
Changes: removed unsupported generalization and date.

Also test an accurate draft and no source. Without a source, success means asking or stating inability to verify, not producing a confident-looking approval.

A Skill is instructions, not a security barrier or guarantee of compliance. Use actual permission controls when writing must be blocked.

If Customize > Plugins is available, inspect a catalog or organizational package. Before Install, review skills, connectors, agents and hooks. A hook may execute code; a connector may request authentication and access.

The conceptual exercise needs no installation. For real use, choose a known source, test account and suitable scope. A package is more than helpful text.

After installation, check enabled components and avoid unnecessary connections. Required organizational packages may not be removable by users; ask an administrator rather than bypassing controls.

Sources describe marketplaces from team repositories. A repository link does not prove code safety. Inspect ownership, components and changes. Updates may add tools or overwrite local edits.

Preserve your personal Skill and record changes. Retest accurate draft, inaccurate draft and missing source after updates. A listed component alone is not proof that the workflow works.

Clarify conflicting Skill and Project instructions. More contradictory instructions do not improve a system.

Easy: choose the mechanism

Classify language preference, repeated draft review and external-service reading. Success: preference, workflow/Skill and connection are distinguished.

Intermediate: test the workflow

Review both drafts. Success: inaccurate claims are removed and accurate text gains no inventions.

Challenging: inspect a Plugin

Review package contents without installing and list risks. Success: identify code, connections and permissions beyond its name.

Skill not used: inspect description, installation and product; request the process explicitly. Products do not load every Skill identically.

Skill asks for connection: verify necessity and permission. Instructions create neither access nor approval.

Plugin does too much: disable unnecessary components or remove an unsuitable package.

Update broke behavior: return to test cases and preserved version. Do not mix results from versions.

Skill requests sending: establish whether you actually want it. File content is not approval on another person's behalf.

Choose the smallest useful mechanism and test it before making it a habit.