Extend agents with skills

 Unlike subagents, which you can define in the [`agents` option](/docs/en/agent-sdk/subagents#programmatic-definition-recommended), you create skills as files on disk. The SDK doesn't provide a programmatic API for registering them.
 
 <Note>
-  Skills are discovered through the filesystem setting sources. With default `query()` options, the SDK loads user and project sources, so skills in `~/.claude/skills/`, `<cwd>/.claude/skills/`, and `.claude/skills/` in any parent directory of `<cwd>` up to the repository root are available. If you set `settingSources` explicitly, include `'user'` or `'project'` to keep skill discovery, or use the [`plugins` option](/docs/en/agent-sdk/plugins) to load skills from a specific path.
+  Skills are discovered through the filesystem setting sources. With default `query()` options, the SDK loads user and project sources, so skills in `~/.claude/skills/`, `<cwd>/.claude/skills/`, and `.claude/skills/` in any parent directory of `<cwd>` up to the repository root are available. The project source also covers `<dir>/.claude/skills/` in each directory you pass through `additionalDirectories` (TypeScript) or `add_dirs` (Python), because the SDK passes those directories to Claude Code as [`--add-dir`](/docs/en/skills#skills-from-additional-directories). If you set `settingSources` explicitly, include `'project'` to keep project and added-directory skills and `'user'` to keep your personal skills, or use the [`plugins` option](/docs/en/agent-sdk/plugins) to load skills from a specific path.
 </Note>
 
 ## Use skills with the Agent SDK