Borrowing it
Nothing to install: this file belongs to tan-yong-sheng/ai-vision-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/tan-yong-sheng/ai-vision-mcp/main/.claude/skills/rbac-permissions-builder/SKILL.mdgit clone --depth 1 https://github.com/tan-yong-sheng/ai-vision-mcpWrote 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/tan-yong-sheng/ai-vision-mcp/rbac-permissions-builder)<a href="https://agentmods.dev/skills/tan-yong-sheng/ai-vision-mcp/rbac-permissions-builder"><img src="https://agentmods.dev/badge/skills/tan-yong-sheng/ai-vision-mcp/rbac-permissions-builder/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/tan-yong-sheng/ai-vision-mcp/rbac-permissions-builder"><img src="https://agentmods.dev/badge/skills/tan-yong-sheng/ai-vision-mcp/rbac-permissions-builder.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00061 | $0.00918 |
| Opus 5 | $0.00030 | $0.00459 |
| Sonnet 5 | $0.00012 | $0.00184 |
| Haiku 4.5 | $0.00006 | $0.00092 |
Grade A, and why
rbac-permissions-builder 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 13d 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.
Copies of this mod
2 near-identical copies found in the catalogue:
- rbac-permissions-builder — 100% identical, 315 lines differ
- rbac-permissions-builder — 100% identical, 315 lines differ
How it starts
The opening of the file, as written. The whole thing — 158 lines — stays where its author put it; the contents beside it link to each section on GitHub.
RBAC/Permissions Builder
Implement flexible role-based access control systems.
Permission Matrix
// Define permissions
export enum Permission {
USER_READ = "user:read",
USER_WRITE = "user:write",
USER_DELETE = "user:delete",
POST_READ = "post:read",
POST_WRITE = "post:write",
ADMIN_ACCESS = "admin:access",
}
// Define roles
export const ROLE_PERMISSIONS = {
user: [Permission.USER_READ, Permission.POST_READ, Permission.POST_WRITE],
moderator: [...userPermissions, Permission.POST_DELETE],
admin: Object.values(Permission), // All permissions
};
// Check permission
export const hasPermission = (user: User, permission: Permission): boolean => {
return ROLE_PERMISSIONS[user.role]?.includes(permission) ?? false;
};
Route Guards (Express)
export const requirePermission = (...permissions: Permission[]) => {
return (req: Request, res: Response, next: NextFunction) => {
if (!req.user) {
return res.status(401).json({ error: "Unauthorized" });
}
const hasAllPermissions = permissions.every((p) =>
hasPermission(req.user, p)
);
if (!hasAllPermissions) {
return res.status(403).json({ error: "Forbidden" });
}
next();
};
};
// Usage
router.delete(
"/users/:id",
authenticate,
requirePermission(Permission.USER_DELETE),
controller.delete
);
Policy Pattern
// policies/user.policy.ts
export class UserPolicy {
static canUpdate(currentUser: User, targetUser: User): boolean {
// Users can update themselves
if (currentUser.id === targetUser.id) return true;
// Admins can update anyone
if (hasPermission(currentUser, Permission.USER_WRITE)) return true;
return false;
}
static canDelete(currentUser: User, targetUser: User): boolean {
// Can't delete yourself
if (currentUser.id === targetUser.id) return false;
// Only admins can delete
return hasPermission(currentUser, Permission.USER_DELETE);
}
}
// Usage in controller
if (!UserPolicy.canUpdate(req.user, targetUser)) {
return res.status(403).json({ error: "Cannot update this user" });
}
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.
- 13d ago First seen · 158 lines · 61 tokens per session scan A e43a2fece53b
rbac-permissions-builder is a skill published in the GitHub repository tan-yong-sheng/ai-vision-mcp (78 stars, last pushed 5mo ago), licensed MIT. It adds 61 tokens to every session and 918 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.
Other skills, from other repositories
mem0-oss-to-platform
Plan and then execute a migration of a project from the mem0 open-source / self-hosted SDK (the local Memory class) to the mem0 Platform / hosted / managed SDK (the MemoryClient class). Use this whenever a developer wants to move, switch, or migrate their mem0 usage off OSS/self-hosted to the hosted API — e.g.…
agui-dotnet-protobuf
Use the protobuf wire transport (instead of the default Server-Sent Events) for an AG-UI connection with the AG-UI .NET SDK — a compact binary event stream negotiated via the Accept header. USE FOR: making an AGUIChatClient prefer protobuf by wiring an AGUIEventStreamHandler with ProtobufEventStreamFormatter (then…
azure-mgmt-botservice-dotnet
Azure Resource Manager SDK for Bot Service in .NET. Management plane operations for creating and managing Azure Bot resources, channels (Teams, DirectLine, Slack), and connection settings. Triggers: "Bot Service", "BotResource", "Azure Bot", "DirectLine channel", "Teams channel", "bot management .NET", "create bot".
fastapi-router-py
Create FastAPI routers with CRUD operations, authentication dependencies, and proper response models. Use when building REST API endpoints, creating new routes, implementing CRUD operations, or adding authenticated endpoints in FastAPI applications.
aws-sdk-java-v2-core
Provides AWS SDK for Java 2.x client configuration, credential resolution, HTTP client tuning, timeout, retry, and testing patterns. Use when creating or hardening AWS service clients, wiring Spring Boot beans, debugging auth or region issues, or choosing sync vs async SDK usage.
migrate-segw-to-rap
Reverse-engineer a SEGW-built OData V2 service (MPC/DPC/MPCEXT/DPCEXT) into a modern RAP V4 service — tables, CDS views (interface + projection), behavior definitions, draft entities, service definition + binding. Use when asked to "migrate this SEGW service to RAP", "convert OData V2 to V4 RAP", "modernize this…