A Trust Pipeline for Agent Skills

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AI agent skills package instructions, code, references, and assets into a format agents can reuse. They are also a new supply-chain surface: a skill can ask an agent to run commands, read files, call tools, fetch remote content, or make decisions on a user’s behalf.

A skill on its own is a set of statements about what it does and how safe it is. The pipeline exists to replace those statements with artifacts a reviewer can check without taking the author’s word for it. Each stage answers one question and leaves behind one piece of evidence.

QuestionEvidence producedStage
Is this skill safe to run?Scan report over the complete bundleSkillSpector, inside SkillEvaluator Tier 1
Does it already exist in the catalog?Semantic overlap reportSkillEvaluator Tier 2
Does it improve an agent’s output?BENCHMARK.md with per-dimension scoresSkillEvaluator Tier 3
What does it do, and who owns it?Skill cardAuthor, reviewed
Is this the artifact that was reviewed?Detached signature over the directoryOMS signing

One Framework, Three Tiers

SkillSpector is part of SkillEvaluator. It is the security scanner that runs as SkillEvaluator’s first tier, not a separate step alongside it. Running SkillEvaluator runs SkillSpector.

  • Tier 1 — Validation. Schema, license, PII, Unicode safety, and the full SkillSpector security scan. Deterministic, and it can fail a skill outright.
  • Tier 2 — Deduplication. Semantic overlap against skills already in the catalog, so the same capability is not published twice under two names.
  • Tier 3 — Live evaluation. The skill is exercised by real agents in a sandbox against a task set, with and without the skill loaded. Each dimension is scored in both conditions, and the difference is the skill’s measured contribution.

A skill can pass every security check and still make an agent worse. Tier 3 is where that shows up. See Evaluate Agent Skills Before Publication for what to ship and how to read the result.

The Release Gate

Use this order for skills intended for enterprise deployment as NVIDIA-Verified:

  1. Author the skill with a narrow purpose, clear triggers, and explicit permissions.
  2. Ship an evaluation task set at evals/evals.json so Tier 3 has something to measure against.
  3. Run SkillEvaluator against the complete skill directory. Tier 1 includes the SkillSpector scan.
  4. Fix high-risk findings, or record why a finding is accepted.
  5. Review the BENCHMARK.md verdict. A skill that does not improve agent performance is not ready, regardless of how it scores on security.
  6. Complete the skill card with owner, license, use case, deployment geography, output shape, risks, and references.
  7. Sign the skill directory and publish the detached skill.oms.sig file with the skill.
  8. Ask consumers or CI to verify the signature before installation.

Scanning, evaluation, and signing solve three different problems. Scanning asks whether the content appears safe to ship. Evaluation asks whether it does any good. Signing asks whether what shipped is what was reviewed.

What Each Layer Catches

LayerPrimary jobExample evidence
SkillSpector scan (SkillEvaluator Tier 1)Detect risky behavior before installationMarkdown, JSON, SARIF, or terminal report
Semantic deduplication (Tier 2)Prevent duplicate capability entering the catalogOverlap report against catalog skills
Live agent evaluation (Tier 3)Measure whether the skill improves agent outputBENCHMARK.md with per-dimension scores and verdict
Skill cardState human-readable intent, ownership, limits, and output behaviorSkill Card.md or equivalent release metadata
OMS signatureVerify integrity and authenticity of the published skill directoryskill.oms.sig plus NVIDIA signing certificate

Every released skill should ship or link to:

  • SKILL.md
  • Supporting scripts/, references/, and assets/ as needed
  • A completed skill card (skill-card.md)
  • A SkillEvaluator report or CI link
  • A Tier-3 evaluation dataset — accepted at evals/evals.json, evals/*.json, eval/*.json, or benchmark/evals.json
  • BENCHMARK.md capturing the benchmark report from the evaluation run
  • skill.oms.sig
  • Verification instructions for the signing certificate and verifier command

Review Questions

Before approval, reviewers should be able to answer:

  • Does the skill description match the behavior of its executable files?
  • Are permissions limited to what the skill actually needs?
  • Are network, shell, file, environment, and MCP capabilities declared in the SKILL.md frontmatter and justified by the skill’s stated use case?
  • Are known risks and mitigations written in plain language?
  • Does the BENCHMARK.md verdict show the skill improving agent output?
  • Does the signature verify against the released directory?

If one of those answers is unclear, the skill is not ready for broad deployment.