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Extend agents with skills

agent-sdk/skills

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agent-sdk/skills Changed · +6 / -2 lines

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 ## Pre-approve tools for skills
 
 <Note>
-  For project and personal skills, the `allowed-tools` frontmatter field applies only when you use the Claude Code CLI directly. In SDK sessions, manage tool approval for these skills through the `allowedTools` option (`allowed_tools` in Python) in your query configuration. Skills [synced from claude.ai](/docs/en/skills#how-claude-code-handles-the-frontmatter-of-a-synced-skill) follow their own frontmatter rules.
+  For project and personal skills, Claude Code applies the [`allowed-tools`](/docs/en/skills#pre-approve-tools-for-a-skill) frontmatter field in SDK sessions. You can also pre-approve tools for these skills through the `allowedTools` option (`allowed_tools` in Python) in your query configuration. Skills [synced from claude.ai](/docs/en/skills#how-claude-code-handles-the-frontmatter-of-a-synced-skill) follow their own frontmatter rules.
 </Note>
 
 Skills run with the session's tools. The example below pre-approves `Read`, `Grep`, and `Glob` with `allowedTools` (`allowed_tools` in Python), so Claude can inspect files while running the [security-check skill](#create-and-dispatch-your-first-skill) without stopping for approval:
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     ```
 
     An empty name reports `Skill names must be non-empty strings.`
+
+    Before TypeScript Agent SDK 0.3.221, the SDK didn't run this check.
   </Tab>
 
   <Tab title="Python">
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     ```
 
     An empty name reports `Skill names must be non-empty strings`.
+
+    Before Python Agent SDK 0.2.129, the SDK didn't run this check.
   </Tab>
 </Tabs>
 
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 ## Next steps
 
-The [Claude Code skills guide](/docs/en/skills) covers authoring in depth. Its guidance applies to SDK sessions, with one exception: for project and personal skills, [Pre-approve tools for skills](#pre-approve-tools-for-skills) replaces the `allowed-tools` frontmatter field with the `allowedTools` option. Start with these sections:
+The [Claude Code skills guide](/docs/en/skills) covers authoring in depth. Its guidance applies to SDK sessions. Start with these sections:
 
 * [Frontmatter reference](/docs/en/skills#frontmatter-reference): every supported field
 * [Pass arguments to skills](/docs/en/skills#pass-arguments-to-skills): `$ARGUMENTS`, `$0`, `$1`, and skill stacking. The [full substitution table](/docs/en/skills#available-string-substitutions) adds named arguments and the `${CLAUDE_*}` variables