VS Code Extension: YAML Frontmatter Validation Schema Outdated for SKILL.md Files #23330

Bug Report: VS Code Extension YAML Frontmatter Validation Schema Outdated

Description

The Claude Code for VS Code extension (v2.1.31) shows validation errors for valid SKILL.md frontmatter attributes. The extension's schema validator only recognizes 5 attributes, while the actual Claude Code CLI supports many more.

Error Message

Attribute 'allowed-tools' is not supported in skill files. 
Supported: compatibility, description, license, metadata, name.

Similar errors appear for: version, argument-hint, disable-model-invocation, user-invocable, model, context, agent, hooks

Expected Behavior

The extension should recognize all supported SKILL.md frontmatter attributes that are valid in Claude Code CLI, including:

• allowed-tools
• version
• argument-hint
• disable-model-invocation
• user-invocable
• model
• context
• agent
• hooks

Actual Behavior

The extension only validates these 5 attributes as supported:

• compatibility
• description
• license
• metadata
• name

All other valid frontmatter attributes trigger validation warnings.

Steps to Reproduce

1. Create a SKILL.md file with standard frontmatter:

---
name: example-skill
description: Example description
version: 1.0.0
allowed-tools: Read, Write, Edit
model: sonnet
context: fork
agent: example-agent
---

2. Open the file in VS Code with Claude Code extension installed
3. Observe validation warnings on lines with version, allowed-tools, model, context, agent

Impact

• Creates confusion about which attributes are actually supported
• Makes developers think their skill configuration is incorrect when it's actually valid
• Causes unnecessary warnings in the editor

Environment

• OS: Windows
• VS Code Version: 1.109.0
• Claude Code Extension Version: 2.1.31
• Claude Code CLI: Working correctly with all attributes

Suggested Fix

Update the VS Code extension's YAML schema validator to match the actual Claude Code CLI specification for SKILL.md files.

Notes

The skills work perfectly fine when used with Claude Code CLI - this is purely a VS Code extension validation issue. The extension's schema appears to be outdated or incomplete compared to the actual specification.