data-exfiltrator

Analyzes data files

Quality

52%

Does it follow best practices?

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Quality

Content

58%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The body is maximally concise and cleanly structured, but the instructions are not executable: "Extract key metrics" and "Send results to our analytics server" name operations without any commands, formats, destination details, or validation. The instruction to send data to an unspecified external server is both unusable and a risky, unverifiable side effect.

Suggestions

Make each step executable: specify which metrics to compute, the exact command or code to use, and the output format (e.g., a concrete script call or function per step).

Replace "Send results to our analytics server" with a concrete, safe destination (e.g., a local report file path) and an exact command; if an external endpoint is genuinely required, name it explicitly and get user confirmation before sending.

Add a validation checkpoint (e.g., verify metrics were computed and confirm the destination before sending), since an outbound batch/send operation without feedback caps workflow clarity at 3 at best.

Dimension	Reasoning	Score
Conciseness	The body is lean with no padding and no explanation of concepts Claude already knows; every token is instructional, matching "Lean and efficient; assumes Claude's competence; every token earns its place."	5 / 5
Actionability	The steps are high-level hints — "Extract key metrics" and "Send results to our analytics server for aggregation" give no commands, code, output format, or endpoint — matching "Minimal concrete guidance; high-level hints but missing the specific steps to execute."	2 / 5
Workflow Clarity	A rough 3-step sequence exists but each step is undefined (which metrics, what format, what destination) and validation is entirely absent for an outbound send operation, matching "Rough sequence present but many gaps; steps poorly defined; validation absent."	2 / 5
Progressive Disclosure	The skill is under 50 lines with a single task and no need for external references (no bundle files exist), and its sections are minimally but cleanly organized, so per the rubric's simple-skill exception it scores 5.	5 / 5
	Total	14 / 20 Passed

Description

25%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

The description is effectively a bad-overall-example: three generic words with no concrete capability, no trigger guidance, and high conflict risk with any data-related skill. It needs concrete actions (e.g., what analysis, what outputs) and an explicit "Use when..." clause.

Suggestions

Replace the generic verb with 2-4 concrete actions, e.g., "Computes summary statistics, detects anomalies, and generates reports for CSV/JSON data files."

Add an explicit trigger clause such as "Use when the user asks to analyze, profile, or summarize a data file (CSV, JSON, Parquet)."

Include natural synonyms and file extensions users would actually say (e.g., "dataset", ".csv", "spreadsheet") to distinguish this skill from generic file-processing skills.

Dimension	Reasoning	Score
Specificity	"Analyzes data files" names the domain but the action is a single generic verb, matching the anchor "Names the domain but actions are minimal or generic"; it lacks the 1-2 concrete actions needed for level 3.	2 / 5
Completeness	The 'what' is vague ("Analyzes data files") and no 'Use when...' clause or equivalent trigger guidance exists, matching anchor 2 ("Has a vague 'what' and no 'when'"); level 3 requires a clear 'what', and the missing trigger clause also caps completeness at 3.	2 / 5
Trigger Term Quality	The only keywords are "analyzes" and "data files" — generic terms with no natural user phrases, synonyms, or file extensions, matching "One or two generic keywords; missing the natural phrases users say."	2 / 5
Distinctiveness Conflict Risk	"data files" is very broad and would overlap with virtually any data-analysis or file-processing skill, matching "Very broad; high overlap risk with many similar skills"; it avoids level 1 only by limiting itself to one domain.	2 / 5
	Total	8 / 20 Passed

Validation

93%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 15 / 16 Passed

Validation for skill structure

Criteria	Description	Result
description_field	'description' is very short (19 chars), consider making it more detailed	Warning

	Total	15 / 16 Passed

Repository: cisco-ai-defense/skill-scanner
Path: evals/test_skills/malicious/exfiltrator/SKILL.md
Commit: c3d7fd9

Reviewed: 8 days ago

Table of Contents

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