nextjs-supabase-auth

Expert integration of Supabase Auth with Next.js App Router Use when: supabase auth next, authentication next.js, login supabase, auth middleware, protected route.

Quality

41%

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Securityby

Passed

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tessl review fix ./skills/nextjs-supabase-auth/SKILL.md

Quality

Content

18%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 is essentially a skeleton or outline with no substantive content. It identifies the right topics (client setup, middleware, OAuth callback, anti-patterns) but provides zero implementation details, code examples, or actionable steps. As-is, it offers no value beyond what Claude already knows about Supabase Auth + Next.js integration.

Suggestions

Add complete, executable code examples for each pattern section (Supabase client creation for server/client/middleware contexts, middleware.ts implementation, auth callback route handler).

Flesh out the Anti-Patterns section with concrete 'wrong' code snippets and their correct alternatives, explaining the specific failure modes.

Define a clear workflow sequence for setting up auth from scratch: 1) create clients → 2) set up middleware → 3) create callback route → 4) verify session flow works, with validation steps.

Either create bundle files for detailed reference material (e.g., MIDDLEWARE.md, CLIENT_SETUP.md) and link to them, or inline the essential code directly in the skill body.

Dimension	Reasoning	Score
Conciseness	The skill avoids lengthy explanations of basic concepts, but includes some filler content like the 'Capabilities' and 'Requirements' sections that read more like metadata than actionable content. The 'When to Use' section is entirely vacuous. The 'core principles' list is reasonable but could be tighter.	3 / 5
Actionability	The skill provides zero concrete code, commands, or executable examples. Every section that should contain implementation details (Client Setup, Auth Middleware, Auth Callback Route, Anti-Patterns) is just a heading with no content. Claude would have no specific guidance to follow beyond vague descriptions.	1 / 5
Workflow Clarity	There is no workflow defined. The 'Patterns' section lists headings (Client Setup, Auth Middleware, Auth Callback Route) but provides no steps, no sequence, and no validation checkpoints. For an auth integration skill involving middleware and OAuth callbacks, the complete absence of any workflow is a critical gap.	1 / 5
Progressive Disclosure	The document has some section structure (Patterns, Anti-Patterns, Related Skills), but no bundle files exist to support the empty pattern sections. References to 'nextjs-app-router' and 'supabase-backend' are mentioned but not linked. Content that should be present (either inline or in referenced files) is simply missing.	2 / 5
	Total	7 / 20 Passed

Description

65%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 has a strong 'Use when' clause with relevant trigger terms that would help Claude select this skill appropriately. However, the 'what' portion is extremely thin — 'Expert integration' tells Claude nothing about what concrete actions this skill enables (e.g., setting up auth middleware, creating login/signup flows, managing sessions, protecting routes). Adding specific capabilities would significantly improve this description.

Suggestions

Replace 'Expert integration of Supabase Auth with Next.js App Router' with specific actions like 'Sets up Supabase authentication in Next.js App Router projects, including login/signup flows, session management, auth middleware configuration, and route protection.'

Add more trigger term variations such as 'sign up', 'session', 'SSR authentication', 'server components', '@supabase/ssr', or 'createClient' to improve matching coverage.

Dimension	Reasoning	Score
Specificity	Names the domain (Supabase Auth with Next.js App Router) but provides no concrete actions beyond 'integration'. It doesn't describe what specific tasks it performs like setting up middleware, creating login pages, managing sessions, etc.	2 / 5
Completeness	Has an explicit 'Use when' clause with concrete trigger phrases, which is good. However, the 'what' portion is weak — 'Expert integration' is vague and doesn't describe specific capabilities. The 'when' compensates but the 'what' needs more substance.	4 / 5
Trigger Term Quality	Includes several natural trigger terms: 'supabase auth next', 'authentication next.js', 'login supabase', 'auth middleware', 'protected route'. These are terms users would naturally use, though it could include more variations like 'sign up', 'session management', 'SSR auth', or 'server components auth'.	4 / 5
Distinctiveness Conflict Risk	The combination of Supabase + Auth + Next.js App Router is fairly specific and unlikely to conflict with generic auth or generic Next.js skills. Minor overlap risk with broader Supabase skills or general Next.js authentication skills.	4 / 5
	Total	14 / 20 Passed

Validation

90%

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 — 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

Repository: administrakt0r/AI-Agents-Safe-Coding-Skills
Path: skills/nextjs-supabase-auth/SKILL.md
Commit: 57c135b

Reviewed: 3 days ago

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