Guide
Best agent Skills for security & auditing
The best agent Skill for security is trail-of-bits — published by the security firm Trail of Bits, it runs CodeQL and Semgrep static analysis plus structured audit workflows, so the agent reviews with a vulnerability bias rather than style nitpicks. For confirmed exploitability use shannon; for Kubernetes hardening use k8s-security-policies.
Some of these Skills take action (shannon executes real exploits) — only run them on targets you are authorized to test. Static-analysis Skills are read-only and safe to run anywhere.
Top pick
trail-of-bitsThe default. Trail of Bits is a top-tier security firm; the skill brings CodeQL + Semgrep static analysis, variant analysis, and structured code auditing into the agent.
Best when: Pre-release vulnerability scans and ongoing security review on a codebase you control.
Ranked
The shortlist
Ranked by fit for the common case, not by raw popularity. Each is a catalogued, verified Skill — open the skill page for the composite score, license, and full install commands.
| Skill | Source | Best when | Verified agents |
|---|---|---|---|
| trail-of-bits | Verified | Pre-release vulnerability scans and ongoing security review on a codebase you control. | Claude Code, Cursor, Codex |
| shannon | Verified | Bug-bounty triage and real-world exploitability validation, only on targets you are authorized to test. | Claude Code |
| k8s-security-policies | Community | Hardening a Kubernetes cluster before it ships, not application-code review. | Claude Code, Cursor |
| ffuf-web-fuzzing | Community | Recon and web-fuzzing tasks inside an authorized pentest scope. | Claude Code |
See every entry, ranked by composite score, in the Security & Auditing category.
Why these
Pick by pick
- 1trail-of-bits
The default. Trail of Bits is a top-tier security firm; the skill brings CodeQL + Semgrep static analysis, variant analysis, and structured code auditing into the agent.
- 2shannon
Autonomous security validation that executes real exploits across 50+ vulnerability types — it confirms exploitability rather than flagging theoretical issues. Action-taking, so authorization matters.
- 3k8s-security-policies
Kubernetes hardening by the book: NetworkPolicies, Pod Security Standards, RBAC, OPA Gatekeeper, and service-mesh mTLS.
- 4ffuf-web-fuzzing
Web fuzzing patterns built around ffuf for content discovery and parameter testing.
FAQ
Common questions
What is the best Claude skill for security?
trail-of-bits. It is published by Trail of Bits, a top-tier security firm, and brings CodeQL + Semgrep static analysis, variant analysis, and structured code auditing into the agent. It is read-only and verified working on Claude Code, Cursor, and Codex.
Which security skill actually proves a vulnerability is exploitable?
shannon. It performs autonomous security validation that executes real exploits across 50+ vulnerability types, so it confirms exploitability instead of flagging theoretical findings. Because it is action-taking, only point it at systems you are explicitly authorized to test.
Is there a skill for Kubernetes security?
Yes — k8s-security-policies. It applies Kubernetes hardening by the book: NetworkPolicies, Pod Security Standards, RBAC, OPA Gatekeeper, and service-mesh mTLS. It is verified on Claude Code and Cursor.
Can a security skill run automatically in CI?
The static-analysis skills (trail-of-bits) fit a pre-merge or scheduled review and are read-only. Action-taking skills like shannon should stay human-gated. Pair a Skill (the methodology) with an MCP server or CLI (the access) for a repeatable pipeline.
Other surfaces
Same job, different tooling
- Security with an MCP server →
Top MCPs ranks the security MCP servers (scanners, SAST, secret detection) that give an agent live tool access.
Related
More best-skill guides
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