agent skills
vs MCP.

What is the difference between Agent Skills and MCP?

An Agent Skill is a directory with a required SKILL.md and optional scripts, references, and assets. Its metadata helps a compatible client decide when to load the full instructions. It is primarily a distribution format for repeatable expertise and workflows.

Model Context Protocol is an open client-server protocol. An MCP host creates a client connection to each MCP server, negotiates capabilities, and exchanges structured messages. Servers can expose executable tools, contextual resources, and reusable prompt templates. They may run locally over standard input/output or remotely over HTTP.

How do Agent Skills and MCP compare?

The shorthand "skills are instructions, MCP is tools" is useful but incomplete. Skills can include scripts and assets. MCP can expose prompts and resources as well as tools. The durable distinction is package versus protocol: one distributes a workflow; the other establishes a structured connection.

When should you use an Agent Skill?

• The agent already has the necessary tools, but needs a reliable method for using them.
• The workflow has ordered steps, quality checks, examples, or an output contract.
• You want a readable artifact that can be versioned, reviewed, and shared across compatible clients.
• The supporting knowledge is small enough to bundle as references, templates, or deterministic scripts.

Examples include a brand editing guide, incident triage checklist, release process, spreadsheet analysis method, or document template. The creation guide shows how to turn one focused job into a valid portable folder.

When should you use MCP?

• The agent needs live records from a database, SaaS product, filesystem, or internal service.
• The capability should expose typed arguments and results instead of relying on shell or prose conventions.
• Authentication, capability discovery, connection lifecycle, or remote execution belongs at the integration layer.
• Several AI applications should connect to the same server through a standard protocol.

Examples include querying Sentry, reading a design from Figma, searching an enterprise knowledge system, or updating a calendar. An MCP server should expose focused capabilities; it does not need to encode every business workflow that uses them.

How can an Agent Skill and MCP work together?

Use MCP to provide the nouns and verbs, then use a skill to define the method. A release skill might query issues, inspect deployments, and update a changelog through MCP tools. The skill decides the order, required evidence, approval points, failure behavior, and finish condition; the servers provide current data and authorized actions.

User request
  -> skill selected from its description
  -> skill defines the release checklist
  -> MCP resource supplies current deployment state
  -> MCP tools query issues and create the release
  -> skill verifies results and stops

Keep the boundary explicit. Name required servers and capabilities in the skill, handle missing tools, require approval for consequential writes, and never assume that a successful tool call proves the workflow outcome.

Which security model should you use for both?

Apply least functionality, least permission, and least autonomy. Review a skill's instructions and code; review an MCP server's operator, source, authentication, scopes, transport, and data boundary. Require human confirmation for destructive or external actions, isolate untrusted content, log sensitive operations, and test with non-production credentials first.

Use the security review checklist before installing third-party content, the installation guide for client paths, or browse agent skills by source and use case. The loop library also shows why explicit stop conditions matter in tool-using workflows.

What do developers ask about Agent Skills and MCP?

Which specifications define Agent Skills and MCP?

This comparison uses the Agent Skills specification, the official MCP introduction, and the MCP architecture documentation. Check product-specific documentation for the capabilities, transports, and skill fields supported by your current client.