security

security is a skill for Claude Code, Codex from rekabytes/opencode-skills. It costs 17 tokens per session (3,088 once invoked), scanned A, original, MIT.

Security guidance covering authentication and access control in a specific application setup. Authentication checks who a user is, while access control checks what that user may view or change.

In plain words
What is it for?
Use it when reviewing or changing login-related code, protected server procedures, and user-data access.
Why use it?
It identifies insecure public data procedures and shows the intended protected approach for user data.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions OpenCode.

Good fit Use it when reviewing or changing login-related code, protected server procedures, and user-data access.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/rekabytes/opencode-skills/security
Install

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.

Any agent
npx skills add rekabytes/opencode-skills --skill security
Clone the repo
git clone --depth 1 https://github.com/rekabytes/opencode-skills

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for security

README.md
[![agentmods](https://agentmods.dev/badge/skills/rekabytes/opencode-skills/security/github.svg)](https://agentmods.dev/skills/rekabytes/opencode-skills/security)
Your own site
<a href="https://agentmods.dev/skills/rekabytes/opencode-skills/security"><img src="https://agentmods.dev/badge/skills/rekabytes/opencode-skills/security/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.

agentmods 80×15 button for security

Your own site · 80×15
<a href="https://agentmods.dev/skills/rekabytes/opencode-skills/security"><img src="https://agentmods.dev/badge/skills/rekabytes/opencode-skills/security.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 17 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,088 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00017 $0.03088
Opus 5.5 $0.00007 $0.01235
Sonnet 5.5 $0.00003 $0.00618
Haiku 4.5 $0.00002 $0.00309

Measured 2mo ago against content hash 374cb41df90d, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

security 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 2mo 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.

templates/skills/security/SKILL.md · 458 lines

How it starts

The opening of the file, as written. The whole thing — 458 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Security Patterns

1. Authentication

Current State

  • Frontend: Logto (OAuth/OIDC) handles user sessions
  • Backend: protectedProcedure exists but NEVER used
  • All 15 routers use publicProcedure (INSECURE for user data)

Code: protectedProcedure vs publicProcedure

// CURRENT (INSECURE) - used everywhere in this codebase
export const userRouter = router({
  getProfile: publicProcedure
    .input(z.object({ userId: z.string() }))
    .query(({ input }) => {
      // ❌ Anyone can access any user's profile!
      return prisma.user.findUnique({ where: { id: input.userId } });
    }),
});

// SHOULD BE - using protectedProcedure
export const userRouter = router({
  getMyProfile: protectedProcedure
    .query(({ ctx }) => {
      // ✅ Only authenticated users can access
      // ctx.user is guaranteed to be populated
      return prisma.user.findUnique({ where: { id: ctx.user.id } });
    }),
});

Auth Context (trpc.ts)

// Current state - ctx.user is ALWAYS null!
export const createContext = async ({ req, res }) => {
  return {
    req,
    res,
    prisma,
    user: null, // Will be populated when token verification is implemented
  };
};

// Protected procedure always throws UNAUTHORIZED
export const protectedProcedure = t.procedure.use(async function isAuthed(opts) {
  const { ctx } = opts;
  if (!ctx.user) {
    throw new TRPCError({ code: 'UNAUTHORIZED' });
  }
  return opts.next({ ctx: { user: ctx.user } });
});

Rules

  • ✅ Use protectedProcedure for any user-specific data
  • ✅ Use publicProcedure only for truly public data (game info, item catalogs)
  • ❌ NEVER use publicProcedure for: user profiles, settings, private data, mutations

2. Input Validation

Current Approach

  • Zod on ALL inputs (this is good)
  • Example patterns from codebase:
// String with length limits
z.string().min(3).max(80)
z.string().email()
z.string().uuid()
z.string().optional()

// Numbers with bounds  
z.number().min(1).max(100)
z.number().min(1).max(50).default(20)

// Booleans with defaults
z.boolean().default(false)

// Enums for fixed values
z.enum(['OPEN', 'CLOSED', 'IN_PROGRESS'])
z.enum(['RANKED', 'CASUAL', 'CUSTOM', 'TOURNAMENT'])

// Arrays
z.array(z.string())
z.array(z.string()).min(1)

// Objects with nested validation
z.object({
  user: z.object({
    id: z.string(),
    username: z.string().optional(),
    avatarUrl: z.string().optional(),
    avatarConfig: z.record(z.string(), z.any()).optional(),
    isGuest: z.boolean().default(false),
  })
})

// Nullable and optional
z.string().nullable()
z.string().optional()
z.string().optional().nullable()

Read the full file on GitHub · 458 lines

Changes

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.

  1. 2mo ago First seen · 458 lines · 17 tokens per session scan A 374cb41df90d

Subscribe to this mod's changes

security is a skill published in the GitHub repository rekabytes/opencode-skills (5 stars, last pushed 7mo ago), licensed MIT. It adds 17 tokens to every session and 3,088 once invoked, about $0.0001 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 2026-08-31.

Related

Other skills, from other repositories

local-ai-agents

Build local-first AI agents that run entirely on a developer workstation with Microsoft Foundry Local and Qwen function-calling models. Covers Small Language Models (SLMs), the OpenAI-compatible local endpoint, sandboxed local tools, local RAG with Chroma, local MCP servers, hybrid cloud/local routing, and the…

microsoft/ai-agents-for-beginners · 200 tokens

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

next-cache-components-adoption

Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…

vercel/next.js · 95 tokens

chat-pet-sprite-creation

Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.

microsoft/vscode · 53 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens

insight-error-page

Write or audit an insight-kind error page for the Next.js dev overlay. Use when creating a new errors/ .mdx page, auditing an existing one, or checking that a page matches the framework fix cards. Covers page structure, title alignment, FixCard cards with Copy prompt button, code snippets, terminology verification…

vercel/next.js · 83 tokens