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AI EngineeringPython

Purple Team

by gaasher

Purple Team is an AI Engineering skill for Claude Code, published by gaasher in Agent-Loop-Skills.

166 stars19 forkson gaasher/Agent-Loop-SkillsAdded 2026/09/08+2% in starsRepository updated 2026/06/30
View source on GitHubDownload repo ZIP
agent-skillsagentic-loopsagentic-workflowsai-agentsanthropicautoresearchclaudeclaude-codedata-analysisliterature-reviewllm-agentsmachine-learningml-autoresearchopen-sourceprompt-engineeringred-teamingscientific-writingskillssubagents
Install in seconds
Install Purple Team
Copy Purple Team into your Claude Code skills folder. Run the command in your terminal, or review the source on GitHub before installing.
terminal
npx degit https://github.com/gaasher/Agent-Loop-Skills/tree/main/loops/purple-team ~/.claude/skills/purple-team

Requires Node.js. Downloads this skill only — not the rest of the repository — into your Claude Code skills folder.

Without Node.js

git clone https://github.com/gaasher/Agent-Loop-Skills.git

Clones the whole repository, then copy the skill’s own directory into your skills folder yourself.

In this catalog

Source file
loops/purple-team/SKILL.md in gaasher/Agent-Loop-Skills
Installs to
~/.claude/skills/purple-team
Collection
One of 25 skills cataloged from this repository
Category
AI Engineering — 3670 skills

What Purple Team does

Purple Team runs red-team and blue-team as separate phases to harden a guardrail, classifier, prompt, or API you own. It repeats find, fix, and re-verify cycles until a fresh attack pass is dry or the cycle budget is reached, then opens a pull request.

Purple Team is cataloged under AI Engineering on DirSkills. Purple Team comes from a repository tagged agent-skills, agentic-loops, agentic-workflows, ai-agents and anthropic.

Documentation

README

Purple Team

The combined red+blue loop — the outer orchestration the red-team skill says "lives outside it." The artifact is a target system (frozen within a phase, patched between phases); the feedback signal is how many new failure classes a fresh attack pass finds against the patched target. Each cycle runs three strictly separated phases — find (red-team), fix (blue-team), re-verify (a fresh red-team pass) — and you repeat until a fresh find stays dry (zero new classes), meaning the target is hardened. Red and blue run as independent agents so the attacker that wrote a catalogue never grades its own patch. On stop it opens a pull request with the cycle history and the patch set.

This is the opening of the README. Read the full README on GitHub.

Frequently asked about Purple Team

  • What else does gaasher publish alongside Purple Team?

    Purple Team is one of 25 skills that DirSkills catalogs from gaasher/Agent-Loop-Skills, the repository it ships in. Its siblings there include Alpha Evolve, Anomaly Investigation and Blue Team. Each one is a separate skill with its own page in this directory, installs the same way Purple Team does, and is maintained by gaasher in that same repository. The rest of the collection is listed on the gaasher/Agent-Loop-Skills page.

  • How does Purple Team compare to other AI Engineering skills?

    Purple Team ranks #3342 by stars among the 3670 AI Engineering skills in this catalog. The most-starred ones next to it are Architecture Decision Records, AI-First Engineering and Agentic OS. DirSkills ranks by the star count of the repository each skill ships in, so that order reflects how popular those repositories are rather than any review of Purple Team against them. Open each page to compare what they document and how they install.

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