nextjs-app-router-fundamentals

Guide for working with Next.js App Router (Next.js 13+). Use when migrating from Pages Router to App Router, creating layouts, implementing routing, handling metadata, or building Next.js 13+ applications. Activates for App Router migration, layout creation, routing patterns, or Next.js 13+ development tasks.

Quality

66%

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tessl review fix ./.agents/skills/nextjs-app-router-fundamentals/SKILL.md

Quality

Content

50%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 is highly actionable with concrete code for App Router migration and patterns, but it is padded with repetitive generateStaticParams examples and re-explained concepts, and it monolithically inlines content that should be split into reference files. The migration workflow lacks integrated validation checkpoints despite destructive cleanup steps.

Suggestions

Collapse the generateStaticParams section: keep one canonical example plus the migration comparison, and remove the redundant Common Patterns / Multiple Dynamic Segments / Dynamic Behavior Configuration restatements to cut substantial padding.

Move the detailed generateStaticParams, routing-pattern, and data-fetching deep dives into separate reference files under references/ and keep SKILL.md as a concise overview with one-level-deep links.

Integrate validation checkpoints into the migration workflow — e.g., after Step 4 run `npm run build` and only proceed to the destructive Step 5 cleanup once the build passes — rather than leaving validation as a detached final checklist.

Dimension	Reasoning	Score
Conciseness	Noticeably verbose: the generateStaticParams section restates the same function across Basic Usage, Common Patterns (3 variants), Multiple Dynamic Segments, Dynamic Behavior Configuration, and Migration — heavily padded — and several sections re-explain Next.js concepts Claude already knows (e.g., Server Component benefits).	2 / 5
Actionability	Mostly executable guidance with concrete, copy-paste TypeScript/TSX and file paths for layouts, metadata, routing, and migration; minor gaps from undefined helpers (getPost, getCategories, db.post.findMany) and a `return (/* render */)` placeholder.	4 / 5
Workflow Clarity	The migration guide has a clear Step 1–5 sequence, but validation lives in a separate end-of-document checklist rather than as inline checkpoints, and the destructive Step 5 (deleting pages/ files) lacks a verify-before-delete feedback loop — capping this at 3 per the destructive-operation rule.	3 / 5
Progressive Disclosure	Section headers are well organized, but this is a ~780-line monolithic SKILL.md with no bundle files; large blocks that belong in separate references (the generateStaticParams deep-dive, data-fetching patterns) are inlined, and cross-skill pointers at the end are not bundle references.	3 / 5
	Total	12 / 20 Passed

Description

83%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 is strong, third-person, and explicitly covers both what the skill does and when to use it with concrete trigger phrases. It is comprehensive for the App Router domain with only minor keyword and coverage gaps.

Dimension	Reasoning	Score
Specificity	Lists several specific actions — "migrating from Pages Router to App Router, creating layouts, implementing routing, handling metadata" — covering the main App Router tasks with only minor gaps (e.g., data fetching not named).	4 / 5
Completeness	Explicitly answers both what ("Guide for working with Next.js App Router...") and when ("Use when migrating..." plus "Activates for App Router migration, layout creation, routing patterns...") with concrete trigger phrases.	5 / 5
Trigger Term Quality	Good natural keyword coverage ("Pages Router", "App Router", "layouts", "routing", "metadata", "Next.js 13+"); a few common variations a user might say (e.g., "SSG", "server components") are missing.	4 / 5
Distinctiveness Conflict Risk	Mostly distinct niche (Next.js 13+ App Router specifics) with clear triggers; minor overlap risk with generic Next.js or React skills, but the App Router framing keeps it well-scoped.	4 / 5
	Total	17 / 20 Passed

Validation

87%

Warnings & errors only

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

Criteria	Description	Result
skill_md_line_count	SKILL.md is long (785 lines); consider splitting into references/ and linking	Warning
allowed_tools_field	'allowed-tools' contains unusual tool name(s)	Warning

	Total	14 / 16 Passed

Repository: AzizBelhassan/timeverse
Path: .agents/skills/nextjs-app-router-fundamentals/SKILL.md
Commit: 9dc2cb4

Reviewed: ~15 hours ago

Table of Contents

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