CtrlK
BlogDocsLog inGet started
Tessl Logo

skill-creator

Guide for creating effective skills. This skill should be used when users want to create a new skill (or update an existing skill) that extends Claude's capabilities with specialized knowledge, workflows, or tool integrations.

68

1.17x
Quality

52%

Does it follow best practices?

Impact

99%

1.17x

Average score across 3 eval scenarios

SecuritybySnyk

Passed

No known issues

Optimize this skill with Tessl

npx tessl skill review --optimize ./plugins/all-skills/skills/skill-creator/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

47%

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

This skill has a well-structured workflow with clear sequential steps and validation checkpoints, but suffers significantly from verbosity. It spends too many tokens explaining what skills are and how they work conceptually, rather than focusing on lean, actionable instructions for creating them. The irony is that a skill about creating concise, effective skills is itself not concise or efficient with its token budget.

Suggestions

Cut the entire 'About Skills' section down to ~10 lines or move detailed explanations of scripts/references/assets to a references/ file, keeping only the directory structure diagram and one-line descriptions in SKILL.md.

Add a concrete example of a complete, well-written SKILL.md (even a short one) so Claude can see the expected output format rather than just reading abstract guidance about what to include.

Replace the descriptive 'When to include' / 'Benefits' / 'Use cases' bullets for each resource type with a single decision table or flowchart that's more token-efficient.

In Step 4's 'Update SKILL.md' section, provide a concrete template with placeholder text rather than just listing questions to answer.

DimensionReasoningScore

Conciseness

The skill is extremely verbose, explaining concepts Claude already knows (what skills are, what scripts/references/assets are, progressive disclosure as a concept). The 'About Skills' section is largely unnecessary background that Claude doesn't need to be taught. Many sections contain redundant explanations (e.g., 'Benefits' bullets that state obvious advantages). The entire content could be cut by 50%+ without losing actionable guidance.

1 / 3

Actionability

The skill provides some concrete guidance like specific script commands (init_skill.py, package_skill.py) and a clear directory structure, but much of the content is descriptive rather than instructive. The examples in Step 2 are illustrative but not executable. The actual SKILL.md writing guidance in Step 4 is relatively vague ('answer the following questions') rather than providing a concrete template or example output.

2 / 3

Workflow Clarity

The 6-step process is clearly sequenced with logical progression from understanding → planning → initializing → editing → packaging → iterating. Each step has clear entry/exit criteria (e.g., 'Conclude this step when there is a clear sense of the functionality'), and Step 5 includes explicit validation before packaging with error recovery guidance (fix errors and run again).

3 / 3

Progressive Disclosure

The skill references scripts (init_skill.py, package_skill.py) but no bundle files were provided, making it impossible to verify these references. The content is monolithic—the lengthy 'About Skills' section and detailed resource type descriptions could be moved to a references file, keeping SKILL.md focused on the workflow. The skill itself doesn't practice the progressive disclosure it preaches.

2 / 3

Total

8

/

12

Passed

Description

57%

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 successfully communicates when to use the skill with an explicit trigger clause, but falls short on specificity—it reads more like a category label than a concrete capability list. The 'what' portion is too abstract ('guide for creating effective skills') without detailing the specific actions performed (e.g., generating frontmatter, structuring markdown, validating fields). Trigger terms are adequate but could be expanded with more natural user phrasings.

Suggestions

Replace the vague 'Guide for creating effective skills' with specific actions like 'Generates skill.md files with proper YAML frontmatter, structured instructions, and validation of required fields'.

Add more natural trigger term variations such as 'skill.md', 'skill file', 'teach Claude', 'custom workflow', or 'extend Claude' to improve matching.

Expand the capability list to include concrete sub-tasks like 'writing description fields, defining tool integrations, structuring step-by-step instructions' to differentiate from generic documentation skills.

DimensionReasoningScore

Specificity

The description uses vague language like 'creating effective skills' and 'extends Claude's capabilities with specialized knowledge, workflows, or tool integrations' without listing concrete actions. It doesn't specify what the skill actually does (e.g., generates YAML frontmatter, writes markdown templates, validates skill structure).

1 / 3

Completeness

It explicitly answers both 'what' (guide for creating effective skills) and 'when' ('should be used when users want to create a new skill or update an existing skill'). The 'Use when' clause is clearly present with explicit triggers.

3 / 3

Trigger Term Quality

It includes some relevant trigger terms like 'create a new skill', 'update an existing skill', and 'skill' itself, which users might naturally say. However, it misses variations like 'skill.md', 'skill file', 'teach Claude', 'custom instruction', or 'workflow template'.

2 / 3

Distinctiveness Conflict Risk

The mention of 'skills' gives it a somewhat specific niche, but phrases like 'specialized knowledge, workflows, or tool integrations' are broad enough to potentially overlap with other meta-skills or documentation-related skills. The core concept of 'creating skills' is fairly distinct but could conflict with general documentation or template generation skills.

2 / 3

Total

8

/

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.

Validation10 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

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

Warning

Total

10

/

11

Passed

Repository
davepoon/buildwithclaude
Reviewed

Table of Contents

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.