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typescript-expert

TypeScript and JavaScript expert with deep knowledge of type-level programming, performance optimization, monorepo management, migration strategies, and modern tooling.

42

Quality

42%

Does it follow best practices?

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

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

SKILL.md
Quality
Evals
Security

Quality

Content

52%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 demonstrates strong TypeScript expertise with concrete, executable examples and a reasonable top-level workflow, but suffers significantly from verbosity and poor progressive disclosure. At 350+ lines with no bundle files, it tries to be a comprehensive TypeScript reference rather than a focused skill document, explaining many concepts Claude already understands. The content would benefit greatly from splitting into focused sub-files and trimming explanatory text.

Suggestions

Split the monolithic content into separate files: move Advanced Type System Expertise, Migration Expertise, Monorepo Management, Modern Tooling, Debugging Mastery, and Code Review Checklist into dedicated referenced files, keeping only the core workflow and brief pointers in SKILL.md.

Remove explanatory text Claude already knows — e.g., what branded types prevent, what ESM is, how error classes work, AI-assisted development tips — and keep only the specific patterns and commands unique to this skill's approach.

Add an explicit feedback loop to the validation step: specify what to do when typecheck or tests fail (e.g., 'If typecheck fails: read errors, fix, re-run; repeat until clean').

Trim the code review checklist to only items that represent non-obvious, project-specific conventions rather than general TypeScript best practices Claude already follows.

DimensionReasoningScore

Conciseness

The skill is significantly verbose at ~350+ lines. It explains many concepts Claude already knows (what branded types are, what ESM is, basic error class patterns, AI-assisted development tips). The code review checklist, decision trees, and resource links add bulk without proportional value. Multiple sections read like a tutorial rather than actionable instructions.

2 / 5

Actionability

The skill provides concrete, executable code examples throughout — branded types, DeepReadonly, validation commands, monorepo config, type testing with Vitest, and debugging CLI commands. Minor gaps exist where guidance is more advisory than executable (e.g., migration table, decision trees, code review checklist items are descriptive rather than actionable).

4 / 5

Workflow Clarity

The numbered workflow in 'When invoked' (steps 0-4) provides a clear sequence with validation at step 4 including specific commands. The safety note about avoiding watch processes is good. However, the validation step could be more explicit about what to do when checks fail (there's no feedback loop for fixing issues found during validation), and the migration workflow lacks explicit checkpoints.

4 / 5

Progressive Disclosure

The skill is a monolithic document with no bundle files to offload content to. The code review checklist, advanced type patterns, migration expertise, debugging mastery, and modern tooling sections all belong in separate referenced files. The skill mentions subagents (typescript-build-expert, typescript-module-expert, typescript-type-expert) but doesn't reference any supporting markdown files for its own extensive content.

2 / 5

Total

12

/

20

Passed

Description

32%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.

This description reads more like a resume summary than a skill description. It lists broad expertise areas without specifying concrete actions Claude can perform, lacks any 'Use when...' trigger guidance, and uses a persona-style framing ('expert with deep knowledge') rather than describing actionable capabilities. The broad scope also creates significant overlap risk with other potential skills.

Suggestions

Replace the persona framing with concrete action verbs describing what the skill does, e.g., 'Writes advanced TypeScript types, configures monorepo tooling (Nx, Turborepo), migrates JavaScript codebases to TypeScript, and optimizes bundle size and runtime performance.'

Add an explicit 'Use when...' clause with natural trigger phrases, e.g., 'Use when the user asks about TypeScript types, generics, .ts/.tsx files, monorepo setup, JS-to-TS migration, or JavaScript performance tuning.'

Narrow the scope or clearly delineate boundaries to reduce conflict risk with other coding skills — specify what this skill handles that a general JavaScript/TypeScript skill would not.

DimensionReasoningScore

Specificity

Names the domain (TypeScript/JavaScript) and lists broad topic areas (type-level programming, performance optimization, monorepo management, migration strategies, modern tooling), but these are categories rather than concrete actions. No specific verbs or actionable capabilities are described.

2 / 5

Completeness

Provides a vague 'what' (expert knowledge in several areas) but completely lacks any 'when' clause or trigger guidance. There is no 'Use when...' or equivalent explicit guidance for when Claude should select this skill. Per rubric guidelines, missing 'Use when...' caps completeness at 3, and the 'what' is also quite vague, placing this at 2.

2 / 5

Trigger Term Quality

Includes relevant keywords like 'TypeScript', 'JavaScript', 'monorepo', 'migration', and 'performance optimization' that users might naturally mention. However, it lacks common variations, file extensions (.ts, .js, .tsx), framework names, or specific tool names that users would reference.

3 / 5

Distinctiveness Conflict Risk

Very broad scope covering TypeScript, JavaScript, performance, monorepos, migrations, and tooling — this could easily overlap with numerous other skills related to JavaScript frameworks, build tools, code optimization, or general programming assistance. The breadth creates high conflict risk.

2 / 5

Total

9

/

20

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

Table of Contents

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