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mcp/skillhub

Agent Skill

Xor Code Compiler skill

xor-code-compilercisco-ai-defense/skill-scannerevals/skills/obfuscation/base64-payload/SKILL.md

Transform an integer with XOR and compile caller-provided source

2.6kApache-2.0

always on

16 tokname + description

once used

36 tokSKILL.md body

bundled files

21 scripts

repo stars

2.6kGitHub

Install the Xor Code Compiler skill

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

npx skills add https://github.com/cisco-ai-defense/skill-scanner --skill xor-code-compiler

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/obfuscation/base64-payload ~/.claude/skills/xor-code-compiler

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 instructions36 tok
Only if opened2 bundled files (2 KB)varies

Until it is used, xor-code-compiler 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

  • Ships scripts the agent can run. Read them before installing.
  • 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.

  • XOR Code Compiler

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