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Agent Skills

Open standard for portable skills across AI agents

open sourceupdated Aug 18, 2026

Agent Skills is the open SKILL.md folder specification for packaging reusable instructions, scripts, references, and assets that compatible AI agents load through progressive disclosure. Originally developed by Anthropic and released as an open standard, it defines the portable format itself—not an example library, marketplace, or hosted agent product.

Agent Skills defines an open, portable folder format for giving AI agents reusable capabilities. Each skill centers on a required SKILL.md file and can include scripts, references, and assets, letting compatible clients discover a concise skill description before loading detailed instructions and resources only when needed. The specification describes this progressive-disclosure flow as discovery, activation, and execution, and its official showcase currently lists 46 clients, including Claude Code, ChatGPT and Codex, Cursor, GitHub Copilot, Gemini CLI, VS Code, Goose, and OpenCode. Originally developed by Anthropic and released as an open standard, the project accepts community contributions while Anthropic reviews client showcase submissions. The repository's code and specification use Apache-2.0, while its documentation uses CC BY 4.0. Agent Skills is the format itself: Anthropic Agent Skills is an example-skills collection, Awesome Agent Skills is a curated directory, and AGENTS.md is a separate repository-guidance convention. The project has no hosted SaaS tier or tagged release. The format itself does not add telemetry, but data handling and execution permissions depend on the client that loads a skill.

Pricing

No paid product or SaaS tier: the Agent Skills format, reference code, and specification are available under Apache-2.0; documentation is CC BY 4.0. Implementing clients, model access, and infrastructure may have separate costs.

Platforms

Portable SKILL.md directories with optional scripts, references, and assets; documented for local, cloud, and sandboxed agents. The pinned official client showcase lists 46 compatible clients.

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FAQ

What is Agent Skills?

Agent Skills is the open SKILL.md folder specification for packaging reusable instructions, scripts, references, and assets that compatible AI agents load through progressive disclosure. Originally developed by Anthropic and released as an open standard, it defines the portable format itself—not an example library, marketplace, or hosted agent product.

Is Agent Skills free?

Yes — Agent Skills is open source and free to use. No paid product or SaaS tier: the Agent Skills format, reference code, and specification are available under Apache-2.0; documentation is CC BY 4.0. Implementing clients, model access, and infrastructure may have separate costs.

Is Agent Skills open source?

Yes — Agent Skills is open source.

What are the best Agent Skills alternatives?

The top editor-verified Agent Skills alternatives are Anthropic Agent Skills, Awesome Agent Skills, AGENTS.md.