# Invalid Agent Skill > Use when testing invalid agent validation - Skill: `tomevault-io/invalid-agent-skill` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/invalid-agent-skill` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/invalid-agent-skill/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/invalid-agent-skill --- This skill has an invalid agent type. Agent must be a built-in (Explore, Plan, general-purpose) or a custom kebab-case name. Invalid_Agent is rejected because underscores are not allowed; use hyphens for kebab-case format. --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/avifenesh) — claim your Tome and manage your conversions.