Skills

• Skill discovery

  Where each harness finds skills and what the model is told about them.

• Skill invocation

  How a skill gets used: by the model on its own or by you.

• Skill frontmatter

  Which SKILL.md frontmatter fields each harness reads.

• OpenAI YAML

  The agents/openai.yaml file Codex reads next to a skill.

• Skills over MCP

  Whether an agent can load skills directly from an MCP server.

• Skill usage

  Whether you can tell which skills get used, and how often.