Comparison · pkgscan.dev
Argus scans it all. SkillSpector only focuses on skills.
Argus runs on any artifact — package, extension, SKILL.md or skill archive. SkillSpector only focuses on skills, so it's the one that names the specific risk: prompt injection, exfiltration, escalation or tool poisoning.
Scan a package or file · All comparisons
Where Argus is different
Generalist vs specialist
Argus reads whatever artifact you give it, skill files included. SkillSpector only focuses on skills, and that focus is exactly why it can name the attack category.
Different failure modes
A malicious skill can be plain text that convinces an agent to leak data; a malicious package ships code. Argus asks whether the artifact's malicious, and SkillSpector tells you which skill risk it resembles.
Both in the same report
pkgscan runs both on the same submission. Argus's malware read and SkillSpector's skill categories sit side by side, each with its own evidence.
No double counting
SkillSpector reports clean when an archive has no skill files, so it doesn't add noise to ordinary packages. Argus still scans the whole artifact.
How Argus and SkillSpector compare
They overlap on skill artifacts and diverge everywhere else. It's about specialisation, not one engine covering a single file type.
| Capability | Argus | Opponent |
|---|---|---|
| What it reads | ||
| Approach | Generalist content + structure analysis | Skill-specific static analysis |
| Package bytes | Yes | Skill files only |
| SKILL.md and skill archives | Yes | Yes |
| Prompt injection and tool poisoning | Can flag malicious content | Named skill categories |
| Executable package code | Yes | No |
| Any artifact type | Packages, extensions, skills, files | Skill files |
| Detection | ||
| Novel malicious behaviour | Yes | Skill-specific |
| Campaign context | Yes | No |
| Reports known CVEs | No | No |
| File-level findings | Yes | Yes |
| Operations | ||
| Runs without setup | Yes | No |
| Open source | No | Yes |
| Runs as a registry publish gate | Yes | No |
| Cost | Free tier, paid plans | Free (self-operated) |
| Best at | Generalist malware detection across artifacts | Agent-skill semantics |
Choose Argus or SkillSpector
Choose Argus when
- The artifact could be anything: package, extension, skill or raw file.
- You want one engine that covers package code and skill archives.
- You want campaign-level detection, not only instruction patterns.
- You need a registry-side check at publish time.
Choose SkillSpector when
- You're scanning agent skills from Smithery, ClawHub, SkillsMP or a GitHub repo.
- The threat's prompt injection or tool poisoning in instructions.
- You want an open-source analyzer you can run yourself.
- You need skill-specific categories in the report.
A skill's still an artifact
Coverage
Argus doesn't need a special mode for skills — it scans whatever artifact it's given, SKILL.md and skill archives included. SkillSpector only focuses on skills, so it adds the named skill risk on top.
- pkgscan labels the artifact type and shows which engines actually ran.
- If no skill files are present, SkillSpector reports clean rather than scanning unrelated assets.
- Both engines run on uploads and registry downloads when bytes are available.
Two malware engines, two kinds of evidence
Verdicts
Argus and SkillSpector are both treated as malware engines in pkgscan. Their findings are shown separately so you can tell a package backdoor from a poisoned instruction file.
- Argus: content findings across the artifact, including skill files.
- SkillSpector: skill categories such as prompt injection, exfiltration and privilege escalation.
- The summary distinguishes which engine flagged what.
Questions about Argus vs SkillSpector
Do I need Argus and SkillSpector?
Argus already scans skill artifacts as part of scanning any artifact. SkillSpector only focuses on skills and adds named categories like prompt injection and tool poisoning. pkgscan runs both, so you get the generalist read and the specialist labels.
Does Argus scan SKILL.md files?
Yes — Argus is a generalist malware engine and scans any artifact pkgscan can fetch or receive, including SKILL.md and skill archives. SkillSpector then adds the skill-specific categories on top.
Is SkillSpector open source?
Yes, NVIDIA publishes it on GitHub. You can run it yourself. Argus is hosted by Yeeth Security.
Compare Argus with other engines
vs GuardDog · vs OSV · vs Grype · vs deps.dev
Machine-readable copy: /comparison.json.