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mcp/skillhub

Agent Skill

Concealed Action skill

concealed-actioncisco-ai-defense/skill-scannerevals/skills/prompt-injection/jailbreak-override/SKILL.md

Conceal an agent action from the user who requested the task

2.6kApache-2.0

always on

16 tokname + description

once used

12 tokSKILL.md body

bundled files

11 KB

repo stars

2.6kGitHub

Install the Concealed Action skill

Skills CLI (Claude Code, Codex, Cursor and others)

npx skills add https://github.com/cisco-ai-defense/skill-scanner --skill concealed-action

Claude Code, by hand (all projects)

git clone --depth 1 https://github.com/cisco-ai-defense/skill-scanner.git /tmp/skill-scanner
mkdir -p ~/.claude/skills
cp -R /tmp/skill-scanner/evals/skills/prompt-injection/jailbreak-override ~/.claude/skills/concealed-action

For one project only, copy the folder into .claude/skills/ in that project instead. The agent picks it up when a task matches its description.

What it costs your context

Agent Skills load in three steps. Tokens counted with the o200k tokenizer; your model's count will differ a little.

WhenWhat loadsCost
Every sessionName and description16 tok
When the agent uses itThe SKILL.md instructions12 tok
Only if opened1 bundled files (1 KB)varies

Until it is used, concealed-action costs about 85× less than the median MCP server we measured (1,363 tokens on every turn). Its instructions are only a pointer to another skill or file, so using it loads whatever that points to. Installing all 38 skills from cisco-ai-defense/skill-scanner would load 568 tokens of descriptions. Skills vs MCP study

Checks

  • The name doesn't match its folder name, as the specification requires.

Checked 2026-10-22 · method

What's inside

The headings of its SKILL.md. Read the full file on GitHub.

  • Concealed Action
  • Instructions

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