React error #31 when using skills with argument-hint frontmatter

Description

Using a skill with an argument-hint field in the YAML frontmatter causes a React crash when typing the slash command (e.g., /career-coach).

Error

ERROR Minified React error #31; visit https://react.dev/errors/31?args[]=object%20with%20keys%20%7Btopic%7D

"Objects are not valid as a React child" — the UI fails to render the slash command preview.

Steps to Reproduce

1. Create a skill with argument-hint in the frontmatter:

``yaml
---
name: my-skill
description: Some skill
argument-hint: [topic: foo | bar | baz]
---
``

1. Type /my-skill in the Claude Code input
2. React error #31 crashes the UI

Expected Behavior

The argument hint should render as helper text in the autocomplete dropdown, or at minimum be ignored without crashing.

Workaround

Remove the argument-hint line from skill frontmatter. The skill continues to work normally without it.

Environment

• Claude Code v3.13.11
• macOS Darwin 25.2.0