Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add roedyrustam/vibes-plug --skill authentication-identity-expertgit clone --depth 1 https://github.com/roedyrustam/vibes-plugWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/roedyrustam/vibes-plug/authentication-identity-expert)<a href="https://agentmods.dev/skills/roedyrustam/vibes-plug/authentication-identity-expert"><img src="https://agentmods.dev/badge/skills/roedyrustam/vibes-plug/authentication-identity-expert/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/roedyrustam/vibes-plug/authentication-identity-expert"><img src="https://agentmods.dev/badge/skills/roedyrustam/vibes-plug/authentication-identity-expert.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 4 findings, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Privilege Escalation · line 52 Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
- high Privilege Escalation · line 219 Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
- high Privilege Escalation · line 251 Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
- high Privilege Escalation · line 269 Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00051 | $0.02795 |
| Opus 5 | $0.00026 | $0.01398 |
| Sonnet 5 | $0.00010 | $0.00559 |
| Haiku 4.5 | $0.00005 | $0.00280 |
Grade A, and why
authentication-identity-expert scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 280 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Authentication & Identity Expert (2026 Edition)
English
Description
Production-grade guide for implementing secure authentication, authorization, and identity management in modern web and mobile applications. Covers Clerk, Supabase Auth, Auth.js v5, Better Auth, JWT patterns, OAuth 2.1, PKCE flows, RBAC/ABAC, passkeys (WebAuthn), and MFA implementation for React 19 / Next.js 15 stacks.
Trigger Conditions
- Working on login/signup flows, session management, or OAuth integration.
- Integrating Clerk, Supabase Auth, Auth.js v5, Better Auth, or Auth0.
- Implementing Role-Based Access Control (RBAC) or Attribute-Based Access Control (ABAC).
- Setting up WebAuthn/Passkeys, MFA/2FA, or SSO.
- Securing Next.js App Router routes with middleware-based auth guards.
- Implementing OAuth 2.1 flows with PKCE for SPAs or mobile apps.
Identity Provider Selection Guide (2026)
| Provider | Best For | Key Strength |
|---|---|---|
| Clerk | SaaS, B2B apps | Built-in organizations, roles, MFA, UI components |
| Supabase Auth | Supabase-powered apps | RLS integration, social login, SSO |
| Auth.js v5 | Next.js self-hosted | Flexible adapters, edge-compatible |
| Better Auth | TypeScript-first self-hosted | Modern DX, built-in 2FA, org management |
| Auth0 | Enterprise, compliance | Enterprise SSO, compliance (SOC2, HIPAA) |
Recommendation: Use Clerk for most new SaaS apps (best DX). Use Supabase Auth if you're already using Supabase. Use Better Auth for full control without vendor lock-in.
Core Security Principles
1. Never Roll Your Own Crypto
- Use
argon2id(preferred) orbcryptfor password hashing — never MD5, SHA1, or plain SHA256. - Use battle-tested libraries:
@node-rs/argon2,bcryptjs. - Minimum: bcrypt cost factor ≥12, argon2id memory ≥64MB.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 9d ago First seen · 280 lines · 51 tokens per session scan A a82a8451a41f
authentication-identity-expert is a skill published in the GitHub repository roedyrustam/vibes-plug (50 stars, last pushed yesterday), licensed MIT. It adds 51 tokens to every session and 2,795 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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