01
The method is the product
Create a skill. Put the trigger and core procedure in SKILL.md; keep deterministic checks in scripts.
All guides
Comparison guide
Agent Skills vs MCP vs plugins.
A skill defines how the agent should work. MCP gives it access to tools and data. A plugin packages extensions for installation and updates.
The short answer
Choose by the thing you need to add.
| Type | What it adds | Typical form | Use it when |
|---|---|---|---|
| Agent Skill | Give the agent instructions, examples, and optional scripts for one type of task. | A folder led by SKILL.md. | You repeat the same procedure or need the same judgment rules across sessions. |
| MCP server | Connect the agent to live tools, data, or external systems through a standard protocol. | A server that exposes tools, resources, or prompts to an MCP client. | The agent must read current data or perform an action in another system. |
| Plugin | Package and distribute one or more extensions through the host product’s installer. | A versioned bundle that can include skills and other host-supported components. | A team or community needs an installable, updateable package instead of copied files. |
Decision guide
Four common cases
02
The connection is the product
Use MCP. Define the smallest useful tools and limit credentials, scopes, and network access.
03
Distribution is the product
Create a plugin after the skill or integration works. Package only the components people need.
04
You need all three
Use a skill for the procedure, MCP for live access, and a plugin to distribute the combined setup.
Skill example
A release-review skill lists the checks, evidence, stop conditions, and rollback questions for every deployment.
MCP example
A deployment MCP server exposes the current build, logs, environment, and rollback actions through limited tools.
Plugin example
A team plugin installs the review skill and the approved deployment connection as one versioned package.
Review the access each layer adds.
Skill: inspect SKILL.md, scripts, filesystem commands, dependencies, and trigger scope.
MCP: inspect the server, authentication, tool schemas, allowed domains, scopes, and write operations.
Plugin: inspect the complete bundle, including every skill, MCP server, hook, executable, dependency, and update source.
Primary sources
Check the current product documentation.
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