analyzing-malware-family-relationships-with-malpedia
Use the Malpedia platform and API to research malware family relationships, track variant evolution, link families to threat actors, and integrate YARA rules for detection across malware lineages.
66
58%
Does it follow best practices?
Impact
Pending
No eval scenarios have been run
Risky
Do not use without reviewing
Optimize this skill with Tessl
npx tessl skill review --optimize ./skills/analyzing-malware-family-relationships-with-malpedia/SKILL.mdQuality
Discovery
82%Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.
This is a strong, specific description that clearly identifies the Malpedia platform and lists concrete threat intelligence actions. Its main weakness is the absence of an explicit 'Use when...' clause, which would help Claude know exactly when to select this skill. The domain-specific terminology provides excellent distinctiveness and trigger term coverage for security researchers.
Suggestions
Add an explicit 'Use when...' clause, e.g., 'Use when the user asks about malware families, malware lineage tracking, Malpedia lookups, threat actor attribution, or YARA rule integration for malware detection.'
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Lists multiple specific concrete actions: 'research malware family relationships', 'track variant evolution', 'link families to threat actors', and 'integrate YARA rules for detection across malware lineages'. | 3 / 3 |
Completeness | Clearly answers 'what does this do' with specific actions, but lacks an explicit 'Use when...' clause or equivalent trigger guidance, which caps this dimension at 2 per the rubric. | 2 / 3 |
Trigger Term Quality | Includes strong natural keywords a security researcher would use: 'Malpedia', 'malware family', 'variant evolution', 'threat actors', 'YARA rules', 'malware lineages', and 'detection'. These cover the domain well. | 3 / 3 |
Distinctiveness Conflict Risk | Highly distinctive due to the specific mention of 'Malpedia platform and API', 'YARA rules', 'malware family relationships', and 'threat actors'. This is a clear niche unlikely to conflict with other skills. | 3 / 3 |
Total | 11 / 12 Passed |
Implementation
35%Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
This skill provides a functional Malpedia API client with reasonable code structure, but suffers from significant verbosity—explaining concepts Claude already knows (malware naming, family relationships, what Malpedia is) and including boilerplate sections. The workflow lacks validation checkpoints (e.g., testing compiled YARA rules, handling API rate limits) and the hardcoded loader-payload chains undermine the API-driven approach. Prerequisites list unused libraries (yara-python, stix2).
Suggestions
Remove the Overview explanation of what Malpedia is, the 'Key Concepts' section explaining malware naming and relationships, and the generic 'When to Use' section—Claude already knows these concepts. This could cut 40+ lines.
Add validation steps: compile YARA rules with `yara.compile()` after extraction, verify API responses match expected schemas, and add rate limiting/retry logic for batch API calls.
Remove `yara-python` and `stix2` from prerequisites or add code that actually uses them (e.g., validate compiled YARA rules with yara-python, export relationships as STIX2 bundles).
Replace the hardcoded `known_chains` dictionary in `build_loader_payload_chain` with actual API-derived relationship data, or clearly document this as a supplementary heuristic with a note about its limitations.
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The skill is excessively verbose. The Overview explains what Malpedia is (Claude already knows), the 'When to Use' section is generic boilerplate, 'Key Concepts' explains basic malware naming conventions and relationship types that Claude already understands, and the 'Malware Family Naming' section explains platform prefixes unnecessarily. The `build_loader_payload_chain` method hardcodes known chains rather than deriving them from the API, adding bulk without value. | 1 / 3 |
Actionability | The code is mostly executable with a proper API client class and concrete API calls, but several issues reduce actionability: the `build_loader_payload_chain` method uses hardcoded data rather than actual API-derived relationships, the YARA compilation function doesn't validate/test the compiled rules, and the `yara-python` and `stix2` libraries listed in prerequisites are never used in the code. The API response handling assumes specific JSON structures without documenting them. | 2 / 3 |
Workflow Clarity | Steps are listed sequentially (query API, map relationships, extract YARA rules) but lack validation checkpoints. There's no error recovery for API failures beyond basic status code checks, no rate limiting consideration for batch API calls, no validation that compiled YARA rules actually compile correctly, and the 'Validation Criteria' section is a checklist of outcomes rather than actionable verification steps integrated into the workflow. | 2 / 3 |
Progressive Disclosure | The content is a monolithic document with all code inline. The large code blocks (especially the MalwareFamilyMapper class) could be split into separate reference files. References are provided at the end but there's no structured navigation to supplementary materials. The skill would benefit from a concise overview with links to detailed API usage, relationship mapping, and YARA compilation guides. | 2 / 3 |
Total | 7 / 12 Passed |
Validation
90%Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.
Validation — 10 / 11 Passed
Validation for skill structure
| Criteria | Description | Result |
|---|---|---|
frontmatter_unknown_keys | Unknown frontmatter key(s) found; consider removing or moving to metadata | Warning |
Total | 10 / 11 Passed | |
- Repository
- mukul975/Anthropic-Cybersecurity-Skills
- Commit
888bbe4
- Reviewed
Table of Contents
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