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nestjs-expert

You are an expert in Nest.js with deep knowledge of enterprise-grade Node.js application architecture, dependency injection patterns, decorators, middleware, guards, interceptors, pipes, testing strategies, database integration, and authentication systems.

Quality

59%

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tessl review fix ./skills/nestjs-expert/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

52%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 delivers strong, concrete Nest.js diagnostics — real issue patterns with frequency/complexity ratings, executable detection and validation commands, and a clear invocation workflow. Its main weaknesses are a ~550-line monolithic structure with zero progressive disclosure (no reference files despite content that warrants them) and substantial padding of framework knowledge Claude already has.

Suggestions

Split the 17 'Problem-Specific Approaches', the Code Review Checklist, and the decision trees into separate reference files (e.g. references/problems.md, references/checklist.md), leaving a lean overview in SKILL.md with clearly signaled one-level-deep links.

Trim content Claude already knows — generic module/decorator/dynamic-module pattern examples, doc-link catalogs, and obvious checklist items — to respect the token budget.

Complete the skeletal code snippets (e.g. the exception filter with only "// Custom error handling") or drop them in favor of the already-good diagnostic guidance.

DimensionReasoningScore

Conciseness

At ~550 lines the body is noticeably verbose: generic checklists ("Caching is implemented for expensive operations"), doc-link catalogs, and standard framework patterns (module/decorator basics) that Claude already knows pad out the genuinely non-obvious material. It is above score 1 because the real GitHub/SO issue patterns and detection commands do add information Claude would not naturally recall.

2 / 5

Actionability

The body provides executable detection commands (grep-based package.json checks), fix-validation commands (npm run build / test / test:e2e), and concrete diagnostic guidance like "The '?' indicates missing provider at that position". Minor gaps remain: several code snippets are skeletons with placeholder comments ("// Custom error handling") rather than complete implementations.

4 / 5

Workflow Clarity

The "When invoked" section gives a numbered 0–4 sequence with escalation routing to other experts, and the validation order "typecheck → unit tests → integration tests → e2e tests" is stated explicitly with corresponding commands and repeated in the Fix Validation section. Not 5 because error-recovery feedback loops (what to do when a checkpoint fails) are implied rather than explicit.

4 / 5

Progressive Disclosure

There are no bundle files at all (no references/, scripts/, or assets/), and all ~550 lines are inlined in SKILL.md — content that clearly belongs in separate files (the 17 problem patterns, the review checklists, the decision trees) is all inline. It scores above 1 only because section headers make the monolith navigable.

2 / 5

Total

12

/

20

Passed

Description

48%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 establishes a clear Nest.js niche but is written as a second-person persona statement rather than a capability description: it lists knowledge areas without any concrete actions and provides no 'Use when...' trigger guidance. Natural trigger terms are adequate but lack common variations users actually type.

Suggestions

Rewrite in third person as concrete capabilities, e.g. "Diagnoses Nest.js dependency-injection errors, configures guards/interceptors/pipes, sets up Passport JWT authentication, and fixes TypeORM/Mongoose integration issues."

Append an explicit trigger clause: "Use when working on a NestJS project, debugging 'Nest can't resolve dependencies' errors, or configuring modules, guards, pipes, or testing."

Include natural user phrasings and synonyms such as "NestJS", "DI error", and "e2e testing" so the skill triggers on how users actually describe the problem.

DimensionReasoningScore

Specificity

The description names the domain richly ("dependency injection patterns, decorators, middleware, guards, interceptors, pipes, testing strategies, database integration") but states no concrete actions — only "deep knowledge of" — matching the anchor 'names the domain but actions are minimal or generic', and the second-person "You are an expert" voice reduces the score by 1 per the rubric guideline.

2 / 5

Completeness

The 'what' is present only as a persona claim enumerating knowledge areas, and the 'when' is entirely absent — no 'Use when...' clause — which caps completeness at 3 per the judging guidelines. It is not 2 because the enumerated domains do make the scope reasonably clear.

3 / 5

Trigger Term Quality

Relevant keywords like "Nest.js", "dependency injection", "guards", "interceptors", and "authentication" are present, but common user variations such as "NestJS" (un punctuated), "Nest can't resolve dependencies", or "DI" are missing, fitting 'some relevant keywords but missing common variations or synonyms'.

3 / 5

Distinctiveness Conflict Risk

"Nest.js" is a clear niche with distinct framework-specific triggers (guards, interceptors, Nest modules), with only minor overlap risk against a generic nodejs-expert or typescript skill.

4 / 5

Total

12

/

20

Passed

Validation

87%

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

Validation — 14 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

skill_md_line_count

SKILL.md is long (557 lines); consider splitting into references/ and linking

Warning

frontmatter_unknown_keys

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

Warning

Total

14

/

16

Passed

Repository

administrakt0r/AI-Agents-Safe-Coding-Skills

Path

skills/nestjs-expert/SKILL.md

Reviewed

Table of Contents

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