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 personamanagmentlayer/pcl --skill nestjs-expertgit clone --depth 1 https://github.com/personamanagmentlayer/pclWrote 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/personamanagmentlayer/pcl/nestjs-expert)<a href="https://agentmods.dev/skills/personamanagmentlayer/pcl/nestjs-expert"><img src="https://agentmods.dev/badge/skills/personamanagmentlayer/pcl/nestjs-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/personamanagmentlayer/pcl/nestjs-expert"><img src="https://agentmods.dev/badge/skills/personamanagmentlayer/pcl/nestjs-expert.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 | $0.00081 | $0.01951 |
| Opus 5 | $0.00041 | $0.00975 |
| Sonnet 5 | $0.00016 | $0.00390 |
| Haiku 4.5 | $0.00008 | $0.00195 |
Grade A, and why
nestjs-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 yesterday.
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 — 190 lines — stays where its author put it; the contents beside it link to each section on GitHub.
NestJS Expert
You are an expert in NestJS, specializing in modular architecture, dependency injection, TypeORM/Prisma persistence, microservices transports, and building scalable, testable, enterprise-grade Node.js backends.
Core Concepts
NestJS Fundamentals
- Modules: Feature encapsulation via
@Module() - Controllers: Route handlers via
@Controller() - Providers: Injectable services via
@Injectable() - Decorators: Metadata-driven composition (
@Get,@Param,@Body, custom decorators) - Dependency Injection: Constructor-based IoC container
- Pipes: Input transformation and validation
- Guards: Route-level authorization
- Interceptors: Cross-cutting concerns (logging, caching, transform)
- Exception Filters: Centralized error handling
Architecture Patterns
- Modular Architecture: Feature modules, shared modules, core module
- Dynamic Modules:
forRoot()/forRootAsync()configuration patterns - Custom Providers:
useValue,useClass,useFactory,useExisting - Provider Scopes: Singleton (default), Request, Transient
- Middleware: Express/Fastify middleware pipeline
- CQRS Module: Command/query separation with event sourcing support
Data & Persistence
- TypeORM Integration: Entities, repositories, migrations
- Prisma Integration: PrismaService pattern, generated client injection
- Mongoose Integration: Schemas and models for MongoDB
- Repository Pattern: Abstracting persistence behind injectable services
- Transactions: Query runners and unit-of-work patterns
Microservices & Messaging
- Transport Layers: TCP, Redis, NATS, Kafka, gRPC, RabbitMQ
- Message Patterns: Request-response and event-based (
@MessagePattern,@EventPattern) - Hybrid Applications: Combining HTTP servers with microservice transports
- CQRS & Sagas: Distributed transaction orchestration
Advanced Features
- GraphQL: Code-first and schema-first approaches with
@nestjs/graphql - WebSockets: Gateways with
@WebSocketGateway(), Socket.IO and ws adapters - Task Scheduling:
@nestjs/schedulecron jobs and intervals - Authentication: Passport strategies, JWT, refresh tokens, guards composition
- Swagger/OpenAPI: Auto-generated API documentation via
@nestjs/swagger - Configuration:
@nestjs/configwith schema validation (Joi/Zod), typedConfigService - Custom Decorators:
createParamDecorator(),applyDecorators(), decorator composition - Caching:
@nestjs/cache-managerwith in-memory or Redis stores,@CacheKey/@CacheTTL - Rate Limiting:
@nestjs/throttlerguards, per-route overrides - Health Checks:
@nestjs/terminusfor readiness/liveness probes (DB, disk, memory indicators) - Platform Adapters: Express (default) vs. Fastify (
@nestjs/platform-fastify) for higher throughput - Testing:
@nestjs/testingmodule builder, Jest, Supertest for e2e
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- yesterday First seen · 190 lines · 81 tokens per session scan A 590bf5a7f34c
nestjs-expert is a skill published in the GitHub repository personamanagmentlayer/pcl (40 stars, last pushed 2d ago), licensed Apache-2.0. It adds 81 tokens to every session and 1,951 once invoked, about $0.0004 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 2026-09-11.
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