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 Asymmetric-al/core --skill nestjs-best-practicesgit clone --depth 1 https://github.com/Asymmetric-al/coreWrote 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/asymmetric-al/core/nestjs-best-practices)<a href="https://agentmods.dev/skills/asymmetric-al/core/nestjs-best-practices"><img src="https://agentmods.dev/badge/skills/asymmetric-al/core/nestjs-best-practices/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/asymmetric-al/core/nestjs-best-practices"><img src="https://agentmods.dev/badge/skills/asymmetric-al/core/nestjs-best-practices.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 | $0.00050 | $0.01142 |
| Opus 5 | $0.00025 | $0.00571 |
| Sonnet 5 | $0.00010 | $0.00228 |
| Haiku 4.5 | $0.00005 | $0.00114 |
Grade A, and why
nestjs-best-practices 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.
The source is not reproduced here
Licensed AGPL-3.0
The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
What ships with it
51 files 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.
- .github/workflows/branch-protection.yml 760 B
- .github/workflows/deploy.yml 1.2 KB
- .gitignore 237 B
- AGENTS.md 159 KB
- README.md 4.4 KB
- rules/_sections.md 2.1 KB
- rules/_template.md 631 B
- rules/api-use-dto-serialization.md 4.3 KB
- rules/api-use-interceptors.md 5.4 KB
- rules/api-use-pipes.md 5.3 KB
- rules/api-versioning.md 4.9 KB
- rules/arch-avoid-circular-deps.md 2.0 KB
- rules/arch-feature-modules.md 2.3 KB
- rules/arch-module-sharing.md 3.8 KB
- rules/arch-single-responsibility.md 2.9 KB
- rules/arch-use-events.md 3.0 KB
- rules/arch-use-repository-pattern.md 2.8 KB
- rules/db-avoid-n-plus-one.md 3.8 KB
- rules/db-use-migrations.md 3.7 KB
- rules/db-use-transactions.md 3.9 KB
- rules/devops-graceful-shutdown.md 5.8 KB
- rules/devops-use-config-module.md 4.3 KB
- rules/devops-use-logging.md 5.6 KB
- rules/di-avoid-service-locator.md 2.9 KB
- rules/di-interface-segregation.md 5.1 KB
- rules/di-liskov-substitution.md 7.1 KB
- rules/di-prefer-constructor-injection.md 2.3 KB
- rules/di-scope-awareness.md 2.6 KB
- rules/di-use-interfaces-tokens.md 2.5 KB
- rules/error-handle-async-errors.md 3.4 KB
- rules/error-throw-http-exceptions.md 3.1 KB
- rules/error-use-exception-filters.md 3.6 KB
- rules/micro-use-health-checks.md 5.8 KB
- rules/micro-use-patterns.md 5.0 KB
- rules/micro-use-queues.md 6.1 KB
- rules/perf-async-hooks.md 2.8 KB
- rules/perf-lazy-loading.md 3.7 KB
- rules/perf-optimize-database.md 3.2 KB
- rules/perf-use-caching.md 3.4 KB
- rules/security-auth-jwt.md 4.0 KB
- rules/security-rate-limiting.md 3.2 KB
- rules/security-sanitize-output.md 3.7 KB
- rules/security-use-guards.md 3.6 KB
- rules/security-validate-all-input.md 3.3 KB
- rules/test-e2e-supertest.md 4.7 KB
- rules/test-mock-external-services.md 4.5 KB
- rules/test-use-testing-module.md 4.3 KB
- scripts/build-agents.ts 8.5 KB runs code
- scripts/build.sh 369 B runs code
- scripts/package-lock.json 8.5 KB
- scripts/package.json 428 B
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 · 131 lines · 50 tokens per session scan A b699d2245ddc
nestjs-best-practices is a skill published in the GitHub repository Asymmetric-al/core (391 stars, last pushed yesterday), licensed AGPL-3.0. It adds 50 tokens to every session and 1,142 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 2026-09-03.
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