tessl-labs/nextjs-api-patterns
Next.js App Router API patterns — Route Handlers, Server Actions, middleware, validation, caching, error handling
92
90%
Does it follow best practices?
Impact
95%
1.58xAverage score across 5 eval scenarios
Passed
No known issues
Quality
Discovery
100%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 is an excellent skill description that clearly defines its scope (Next.js App Router API patterns), lists specific capabilities, and provides explicit trigger guidance including edge cases. The description effectively communicates both the technical domain and when to apply it, even for seemingly simple requests that might otherwise be missed.
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Lists multiple specific concrete actions and patterns: 'Route Handlers, Server Actions, middleware, error boundaries, validation, streaming, caching, and runtime selection' - these are all specific, actionable technical concepts. | 3 / 3 |
Completeness | Clearly answers both what ('Covers Route Handlers, Server Actions, middleware...') and when ('Apply even when the task only asks for "an API endpoint" or "a form"'). The explicit trigger guidance about applying to seemingly simple requests is excellent. | 3 / 3 |
Trigger Term Quality | Includes natural keywords users would say: 'Next.js', 'App Router', 'API endpoint', 'form', 'Route Handlers', 'Server Actions', 'middleware'. These cover both technical terms and casual requests like 'an API endpoint' or 'a form'. | 3 / 3 |
Distinctiveness Conflict Risk | Highly distinctive with clear niche: specifically targets 'Next.js App Router' patterns, distinguishing it from general React skills, other Next.js versions (Pages Router), or generic API skills. The mention of 'App Router model' unique concerns further narrows scope. | 3 / 3 |
Total | 12 / 12 Passed |
Implementation
77%Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
This is a strong, highly actionable skill with excellent executable code examples and clear workflow patterns. The content successfully covers Next.js App Router patterns comprehensively with proper validation, error handling, and caching guidance. Minor improvements could include tightening some explanatory prose and potentially splitting detailed patterns into referenced files for better progressive disclosure.
Suggestions
Trim the 'Why This Matters From Day One' section to a brief bullet list - Claude doesn't need the detailed explanations of what goes wrong
Consider moving the full Route Handler and Server Action code examples to a separate EXAMPLES.md file, keeping only minimal quick-start snippets in the main skill
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The content is mostly efficient with good code examples, but includes some explanatory sections that could be tightened (e.g., 'Why This Matters From Day One' explains concepts Claude likely knows). The comparison table and gotchas are valuable, but some prose could be trimmed. | 2 / 3 |
Actionability | Excellent actionability with fully executable, copy-paste ready code examples for Route Handlers, Server Actions, middleware, error boundaries, and streaming. Every pattern includes complete TypeScript code with proper imports and error handling. | 3 / 3 |
Workflow Clarity | Clear workflows with explicit validation steps throughout. The Route Handler pattern shows try/catch with validation, Server Actions include revalidation steps, and the checklist provides a comprehensive verification workflow. Feedback loops are present (validate -> handle errors -> respond). | 3 / 3 |
Progressive Disclosure | Content is well-organized with clear sections and a logical flow from concepts to implementation to gotchas. However, at ~400 lines, some content (like the full API reference patterns) could be split into separate files. The verifiers section references external files appropriately, but the main content is monolithic. | 2 / 3 |
Total | 10 / 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.
Validation — 10 / 11 Passed
Validation for skill structure
| Criteria | Description | Result |
|---|---|---|
frontmatter_unknown_keys | Unknown frontmatter key(s) found; consider removing or moving to metadata | Warning |
Total | 10 / 11 Passed | |
Reviewed
Table of Contents