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matplotlib

Matplotlib is Python's foundational visualization library for creating static, animated, and interactive plots.

41

Quality

43%

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tessl review fix ./plugins/AI-Agents-Safe-Coding-Skills/skills/matplotlib/SKILL.md

The canonical home for this skill is matplotlib in administrakt0r/AI-Agents-Safe-Coding-Skills

SKILL.md
Quality
Evals
Security

Quality

Content

50%Scale 1-5

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

This skill reads more like a comprehensive matplotlib tutorial or documentation page than a focused skill for Claude. It extensively covers concepts Claude already knows (what plot types are, matplotlib's object hierarchy, basic Python library usage) while providing good executable code examples. The main weakness is verbosity and over-explanation—roughly half the content could be removed without losing actionable value.

Suggestions

Remove the 'Core Concepts' hierarchy explanation, 'When to Use This Skill' section, 'Integration with Other Tools', and 'Additional Resources'—Claude already knows all of this.

Trim the plot types section to just the code patterns without describing what each plot type is used for (e.g., remove 'Time series, continuous data, trends' descriptions).

Either provide the referenced bundle files (references/plot_types.md, references/styling_guide.md, etc.) or remove the references and keep only the essential inline content.

Add a brief validation step to the workflow, such as checking the saved file exists and has expected size, or verifying plot renders correctly before saving.

DimensionReasoningScore

Conciseness

Significantly verbose for a Claude skill. Explains concepts Claude already knows well (matplotlib hierarchy, what a Figure/Axes is, what line plots vs scatter plots are, two interfaces). The 'When to Use This Skill' section, 'Core Concepts' hierarchy explanation, 'Integration with Other Tools' list, and 'Additional Resources' links are all unnecessary padding. Much of this is standard matplotlib documentation rather than novel guidance.

2 / 5

Actionability

Provides executable, copy-paste ready code examples for most common operations (basic plots, subplots, saving, 3D, styling). The code is concrete and functional. Minor gaps: some examples use undefined variables (x, y1, y2, categories, values, data) without setup, and the referenced scripts (plot_template.py, style_configurator.py) don't exist in the bundle.

4 / 5

Workflow Clarity

The workflows are presented as numbered sections but lack validation checkpoints. For a visualization skill, there's no guidance on verifying output quality, checking for rendering issues, or handling errors (e.g., what if savefig fails, what if data is malformed). The 'Common Gotchas' section partially addresses this but reactively rather than as part of the workflow. Since this is not a destructive/batch operation skill, the cap doesn't apply, but the workflows are still more like a catalog than a guided process.

3 / 5

Progressive Disclosure

References four separate reference files and two scripts, which is good structure in principle, but none of these files exist in the bundle. The main SKILL.md is also quite long (~300 lines) with substantial inline content that could be better distributed. The styling guide, plot types catalog, and API reference are partially inlined AND referenced externally, creating redundancy.

3 / 5

Total

12

/

20

Passed

Description

36%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 reads like a marketing tagline for Matplotlib rather than a functional skill description. It lacks concrete actions, has no 'Use when...' clause to guide skill selection, and misses many natural trigger terms users would employ when requesting visualization help.

Suggestions

Add a 'Use when...' clause with trigger terms like 'chart', 'graph', 'scatter plot', 'histogram', 'bar chart', 'matplotlib', 'figure', '.png export'.

List specific concrete actions such as 'create bar charts, line plots, scatter plots, histograms, customize axes and legends, save figures to image files'.

Differentiate from other visualization libraries by specifying when to choose Matplotlib over alternatives like Seaborn or Plotly.

DimensionReasoningScore

Specificity

Names the domain (Matplotlib/Python visualization) but actions are minimal and generic — 'creating static, animated, and interactive plots' is broad and doesn't list concrete actions like 'generate bar charts, customize axes, export figures.'

2 / 5

Completeness

Has a vague 'what' (creating plots) but completely lacks a 'when' clause. There is no 'Use when...' guidance, and the description reads more like a library tagline than a skill selection guide.

2 / 5

Trigger Term Quality

Includes 'Matplotlib', 'Python', 'visualization', 'plots' which are relevant keywords, but misses common natural terms users would say like 'chart', 'graph', 'figure', 'plot data', '.png', 'bar chart', 'scatter plot', 'histogram'.

3 / 5

Distinctiveness Conflict Risk

Mentioning 'Matplotlib' specifically helps distinguish it from other visualization skills (e.g., Seaborn, Plotly), but the broad 'visualization library' framing could overlap with any Python plotting skill.

3 / 5

Total

10

/

20

Passed

Validation

81%

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

Validation9 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

9

/

11

Passed

Repository
administrakt0r/AI-Agents-Safe-Coding-Skills
Reviewed

Table of Contents

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