sns-topic

sns-topic is a skill for Claude Code from AlexK020908/infra-designer. It costs 0 tokens per session (277 once invoked), scanned A, original, MIT.

An AWS SNS topic for publish/subscribe messaging: one published message is sent to every subscriber. Unlike a queue, it broadcasts messages rather than giving each message to only one consumer.

In plain words
What is it for?
Use it to broadcast events to SQS queues or, for light loss-tolerant tasks, directly to AWS Lambda functions.
Why use it?
It lets different consumers receive the same event independently, while paired queues provide buffering, retries, and pacing for important work.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the infra-designer plugin — 19 skills, 5 commands shipped together

Good fit Use it to broadcast events to SQS queues or, for light loss-tolerant tasks, directly to AWS Lambda functions.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/alexk020908/infra-designer/sns-topic
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 AlexK020908/infra-designer --skill sns-topic
Clone the repo
git clone --depth 1 https://github.com/AlexK020908/infra-designer

Made for: Claude Code.

Or install infra-designer, the plugin that ships this one along with the rest of its 19 skills, 5 commands.

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 sns-topic

README.md
[![agentmods](https://agentmods.dev/badge/skills/alexk020908/infra-designer/sns-topic/github.svg)](https://agentmods.dev/skills/alexk020908/infra-designer/sns-topic)
Your own site
<a href="https://agentmods.dev/skills/alexk020908/infra-designer/sns-topic"><img src="https://agentmods.dev/badge/skills/alexk020908/infra-designer/sns-topic/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 sns-topic

Your own site · 80×15
<a href="https://agentmods.dev/skills/alexk020908/infra-designer/sns-topic"><img src="https://agentmods.dev/badge/skills/alexk020908/infra-designer/sns-topic.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 277 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 $0.00000 $0.00277
Opus 5 $0.00000 $0.00138
Sonnet 5 $0.00000 $0.00055
Haiku 4.5 $0.00000 $0.00028

Measured 12d ago against content hash da6a50ebdf75, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

sns-topic 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 12d 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.

infra-plugin/components/aws/sns-topic/SKILL.md · 18 lines

What it actually says

aws.sns.topic

Pub/sub fan-out: one published message is delivered to EVERY subscriber, where a queue delivers each message to ONE consumer. Config knob: fifo (false).

Fan-out pattern

  • The standard pattern is topic → one aws.sqs.queue per consumer type: SNS does the broadcast, each queue gives its consumer independent retries, DLQ, and pacing.
  • Direct topic → aws.lambda.function subscriptions suit light, loss-tolerant async work; there is no queue buffering or redrive between SNS and the function beyond SNS's own retry policy, so anything important should go through a queue first.

Delivery, not storage

  • SNS is delivery, not storage: no replay, no retention, no log. If a subscriber is broken and its queue policy is wrong, messages are simply gone — always pair critical fan-out with SQS subscriptions.

FIFO & filtering

  • fifo: true gives ordered, deduplicated fan-out but may only feed FIFO queues, and inherits FIFO throughput caps. Default to standard.
  • Message filter policies are application-level configuration — note them when consumers want subsets.

Edges & IAM

  • Edge kinds: compute → topic is iam (publish); topic → queue/function is data (subscription). Publishers get {NODE}_TOPIC_ARN in env.
Files

What ships with it

3 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. 12d ago First seen · 18 lines · 0 tokens per session scan A da6a50ebdf75

Subscribe to this mod's changes

sns-topic is a skill published in the GitHub repository AlexK020908/infra-designer (2 stars, last pushed 2mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 277 tokens. 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.