Claude Code Guide is a reference collection for configuring and using Claude Code, Anthropic’s command-line coding agent. Developers use it to learn commands, skills, agents, MCP, automation, security, integrations, and troubleshooting. Its catalogue add-ons provide many of the documented skills and agents.
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 zebbern/claude-code-guide --skill authentication-patternsgit clone --depth 1 https://github.com/zebbern/claude-code-guideWrote 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/zebbern/claude-code-guide/authentication-patterns)<a href="https://agentmods.dev/skills/zebbern/claude-code-guide/authentication-patterns"><img src="https://agentmods.dev/badge/skills/zebbern/claude-code-guide/authentication-patterns/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/zebbern/claude-code-guide/authentication-patterns"><img src="https://agentmods.dev/badge/skills/zebbern/claude-code-guide/authentication-patterns.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 35 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 37 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 46 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 158 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 | $0.00047 | $0.01894 |
| Opus 5.5 | $0.00019 | $0.00758 |
| Sonnet 5.5 | $0.00009 | $0.00379 |
| Haiku 4.5 | $0.00005 | $0.00189 |
Grade A, and why
authentication-patterns 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 1mo 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 — 167 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Authentication Patterns Skill
Reference for implementing secure, production-ready authentication.
WHEN_TO_USE
Apply this skill when implementing authentication in a project, reviewing existing auth flows for security issues, choosing between auth providers, or migrating between auth strategies. Use the security checklist before shipping any auth-related change.
AUTH_APPROACHES
| Approach | How It Works | Best For | Drawbacks |
|---|---|---|---|
| Session-based | Server stores session in DB/Redis, client holds session ID cookie | Traditional server-rendered apps, apps needing instant revocation | Requires server-side storage, harder to scale horizontally without shared store |
| JWT (stateless) | Server signs token, client sends it on each request | API-first apps, microservices, mobile clients | Cannot revoke without blocklist, token size grows with claims |
| OAuth 2.0 / OIDC | Delegates auth to external provider (Google, GitHub, etc.) | Social login, enterprise SSO, reducing auth responsibility | More complex flow, depends on external provider availability |
| Passkeys / WebAuthn | Cryptographic key pair, no passwords | High-security apps, passwordless UX | Limited browser support legacy, user education needed |
Decision Guide
- Server-rendered app with simple needs → Session-based
- SPA or mobile app calling APIs → JWT with refresh token rotation
- Want social login or SSO → OAuth 2.0 / OIDC
- Greenfield with modern UX goals → Passkeys + OAuth fallback
JWT_BEST_PRACTICES
Token Lifecycle
Login → Access Token (short-lived) + Refresh Token (long-lived, rotated)
│
├─ Access Token: 15 min expiry, sent via httpOnly cookie or Authorization header
│
└─ Refresh Token: 7-30 day expiry, stored in httpOnly secure cookie
│
└─ On use: issue new access + new refresh token, invalidate old refresh token
Rules
- [P0-MUST] Set short expiry on access tokens (15 minutes or less).
- [P0-MUST] Store tokens in
httpOnly,Secure,SameSite=Laxcookies — never inlocalStorageorsessionStorage. - [P0-MUST] Implement refresh token rotation — each refresh token is single-use.
- [P0-MUST] Maintain a server-side blocklist for revoked refresh tokens.
- [P1-SHOULD] Include only essential claims in JWT payload (sub, iat, exp, role). Keep it small.
- [P1-SHOULD] Use asymmetric signing (RS256 or ES256) for distributed systems; symmetric (HS256) for single-service only.
- [P1-SHOULD] Validate
iss,aud, andexpclaims on every request. - [P2-MAY] Use JWE (encrypted JWT) when token payload contains sensitive data.
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.
- 1mo ago First seen · 167 lines · 47 tokens per session scan A 4c26152037ad
authentication-patterns is a skill published in the GitHub repository zebbern/claude-code-guide (4,664 stars, last pushed yesterday), licensed MIT. It adds 47 tokens to every session and 1,894 once invoked, about $0.0002 per session on Opus 5.5. 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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