aws-essentials

aws-essentials is a skill for Claude Code, Codex from ericrisco/rsc-harness. It costs 89 tokens per session (2,933 once invoked), scanned A, original, MIT.

A guide for setting up the core AWS services for a small product. AWS is Amazon's cloud platform, and these services provide storage, databases, servers, delivery, and access control.

In plain words
What is it for?
Use it to harden an AWS account, create private S3 storage, encrypted RDS databases, ECS container hosting, CloudFront delivery, and narrowly scoped IAM permissions.
Why use it?
It helps avoid common cloud security mistakes such as public file buckets, overly broad permissions, unencrypted databases, and long-lived access keys.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/ericrisco/rsc-harness/aws-essentials
Any agent
npx skills add ericrisco/rsc-harness --skill aws-essentials
Clone the repo
git clone --depth 1 https://github.com/ericrisco/rsc-harness

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 aws-essentials

README.md
[![agentmods](https://agentmods.dev/badge/skills/ericrisco/rsc-harness/aws-essentials.svg)](https://agentmods.dev/skills/ericrisco/rsc-harness/aws-essentials)
Your own site
<a href="https://agentmods.dev/skills/ericrisco/rsc-harness/aws-essentials"><img src="https://agentmods.dev/badge/skills/ericrisco/rsc-harness/aws-essentials.svg" alt="Measured on agentmods" height="20"></a>
Per session 89 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,933 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00089 $0.02933
Opus 5 $0.00044 $0.01466
Sonnet 5 $0.00018 $0.00587
Haiku 4.5 $0.00009 $0.00293

Measured 5d ago against content hash c468c4dfe14a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

aws-essentials 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 5d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/verify.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

skills/aws-essentials/SKILL.md · 207 lines

How it starts

The opening of the file, as written. The whole thing — 207 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AWS essentials — the core surface a small product needs, secured from the first command

Stand up the foundational AWS services a one-app product actually uses — IAM, S3, ECS Fargate, RDS, CloudFront — with the security defaults that prevent the incidents (public buckets, god-mode app roles, long-lived keys, unencrypted databases). Pick the right tier for small (one app, modest traffic, two engineers), provision it correctly, and wire it without foot-guns.

account hardening → IAM (roles + scoped policies) → S3 (private) / RDS (encrypted) / ECS Fargate → CloudFront (OAC) → infra exists, wired, least-privilege

Service decision table

Need Use Use instead if
Object/file storage (uploads, assets, backups) S3 (private bucket)
Relational data (users, orders, anything with joins) RDS (Postgres/MySQL) key-value / serverless access pattern → dynamodb skill
Long-running container/API ECS Fargate steady ~70%+ CPU 24/7 → EC2 launch type with Savings Plans/Spot; GPU or >120 GB RAM → EC2
Static site / SPA + public assets S3 + CloudFront edge functions / global KV → ../cloudflare/SKILL.md
Tiny app, no real AWS need yet be honest → ../vercel/SKILL.md or ../deployment/SKILL.md you genuinely need AWS primitives → stay here

Fargate cold start is ~30–60 s; for spiky/variable small-product load its operational simplicity (no host patching, per-second billing, strong task isolation) wins. EC2 launch type only earns its host-management cost at sustained high utilization. (ECS Managed Instances, Sept 2025, is a newer hybrid — out of scope for a first setup.)

Account zero-day hardening checklist

Do this once, before anything else. Each line has a reason; skip none.

  • Enable MFA on the root user — prefer a passkey / security key (phishing-resistant). Root with no MFA is the single highest-blast-radius account.
  • Stop using root for daily work — root is for the handful of root-only tasks (close account, change support plan). Everything else uses an IAM identity.
  • Create an admin identity via IAM Identity Center (or an assumable admin role). Humans log in to a role with temporary creds, not a static user.
  • Delete any root access keys — root should have zero access keys. If one exists, it is a liability with no upside.
  • No long-lived IAM-user access keys for apps or CI — apps use task roles, CI uses OIDC (see ../deployment/SKILL.md).
  • Set your home region and create resources there consistently (one exception below: ACM certs for CloudFront must be in us-east-1).
  • Create a billing/cost budget alarm — a misconfigured resource should page you, not surprise you on the invoice.

Read the full file on GitHub · 207 lines

Files

What ships with it

5 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.

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. 5d ago First seen · 207 lines · 89 tokens per session scan A c468c4dfe14a

Subscribe to this mod's changes

aws-essentials is a skill published in the GitHub repository ericrisco/rsc-harness (60 stars, last pushed 2d ago), licensed MIT. It adds 89 tokens to every session and 2,933 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 2026-08-30.