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agent-development

This skill should be used when the user asks to "create an agent", "write an agent", "build an agent", or wants to add new agent capabilities to Claude Code.

68

1.84x
Quality

62%

Does it follow best practices?

Impact

96%

1.84x

Average score across 3 eval scenarios

SecuritybySnyk

Passed

No findings from the security scan

Fix and improve this skill with Tessl

tessl review fix ./plugins/toolkit/skills/agent-development/SKILL.md
SKILL.md
Quality
Evals
Security

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.

A compact, well-sectioned body with a concrete frontmatter example and useful color conventions, but it reads as reference notes rather than a creation guide — the actual agent-creation workflow (file location, required fields, steps) is absent.

Suggestions

Add the essential how-to up front: where agent definition files live (e.g. .claude/agents/) and which frontmatter fields are required (name, description) versus optional (color, tools).

Restructure around the creation workflow (write the definition file -> set name/description/tools -> choose a color -> changes hot-reload) so sections sequence into a process rather than standalone topics.

Trim the consequence sentence in Permission Denial Resilience ('This makes autonomous workflows more resilient and reduces the need for human intervention') or convert it into guidance on what to do when a subagent hits a permissions wall.

DimensionReasoningScore

Conciseness

The body is lean and table-driven ("Set in YAML frontmatter" with a copy-paste example and a compact color table), assuming Claude's competence. Only minor over-explanation could be trimmed, e.g. "This makes autonomous workflows more resilient and reduces the need for human intervention", which explains consequences rather than instructing — matching 'efficient; minor instances of over-explanation'.

4 / 5

Actionability

The YAML frontmatter example (name/description/color) and the color-conventions table are concrete, but key execution details are missing: no file location for agent definitions and no listing of required vs optional frontmatter fields. "Permission Denial Resilience" is purely descriptive with no instruction — fitting 'some concrete guidance but incomplete; missing key details'.

3 / 5

Workflow Clarity

There is no sequence for creating an agent — sections are topical (colors, behavior, a post-hoc note) rather than procedural, and the frontmatter snippet appears with no instruction on where to put it or which fields are mandatory. The simple-skill exemption does not apply because the single action (write an agent definition) is not unambiguous; this matches 'rough sequence present but many gaps; steps poorly defined'.

2 / 5

Progressive Disclosure

The body is under 50 lines, no bundle files (references/, scripts/, assets/) exist, and it is organized into clear ## / ### sections with no content that warrants external files. Per the simple-skill guideline, well-organized sections alone earn full marks here.

5 / 5

Total

14

/

20

Passed

Description

47%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.

A natural, explicit trigger description that clearly says when to invoke the skill, but it never states what the skill actually does. The missing capability statement leaves the completeness and specificity dimensions weak despite strong trigger phrasing.

Suggestions

Add a 'what' clause stating concrete actions, e.g. 'Creates and edits Claude Code agent definitions (name, description, tools, color) in .claude/agents/.'

Mention the concrete artifacts the skill works with (agent definition files and their frontmatter fields) so capabilities are explicit rather than inferred from triggers.

Include a few more natural trigger variations such as 'subagent', 'add an agent', or 'define an agent' to broaden keyword coverage.

DimensionReasoningScore

Specificity

The description names the domain ("add new agent capabilities to Claude Code") but states no concrete skill actions — phrases like "create an agent" and "build an agent" are user-side triggers, not descriptions of what the skill does (e.g. writing agent definition files). It matches the anchor 'Names the domain but actions are minimal or generic' rather than score 3, which requires 1-2 concrete actions by the skill itself.

2 / 5

Completeness

Only the 'when' is present ("This skill should be used when the user asks to...") with no 'what' — exactly the anchor 'only when is present without what'. It is not score 3 because no capability statement (what the skill does) is explicitly stated, and not score 1 because the 'when' is explicit and specific.

2 / 5

Trigger Term Quality

"create an agent", "write an agent", "build an agent" are natural verb-synonym phrases users would actually say, giving good keyword coverage. It falls short of score 5 because common variations like "subagent", "add an agent", or file-path/extension terms are missing.

4 / 5

Distinctiveness Conflict Risk

Scoping to "Claude Code" gives it a mostly distinct niche with clear triggers. Minor overlap risk remains with general AI/LLM agent-building skills triggered by the generic phrase "build an agent", keeping it below score 5.

4 / 5

Total

12

/

20

Passed

Validation

100%

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

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository

dwmkerr/claude-toolkit

Path

plugins/toolkit/skills/agent-development/SKILL.md

Reviewed

Table of Contents

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