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 jamestelfer/sandy --skill cligit clone --depth 1 https://github.com/jamestelfer/sandyWrote 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/jamestelfer/sandy/cli)<a href="https://agentmods.dev/skills/jamestelfer/sandy/cli"><img src="https://agentmods.dev/badge/skills/jamestelfer/sandy/cli/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/jamestelfer/sandy/cli"><img src="https://agentmods.dev/badge/skills/jamestelfer/sandy/cli.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 | $0.00045 | $0.01743 |
| Opus 5.5 | $0.00018 | $0.00697 |
| Sonnet 5.5 | $0.00009 | $0.00349 |
| Haiku 4.5 | $0.00005 | $0.00174 |
Grade A, and why
sandy 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 7d 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.
How it starts
The opening of the file, as written. The whole thing — 192 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Sandy
Sandy executes TypeScript scripts in disposable sandboxed environments (Shuru microVMs or Docker containers) with AWS credentials from IMDS.
The CLI uses explicit sessions. Create one first, then run scripts from that session’s scripts/ directory.
Setup
Read the scripting guide before writing scripts:
sandy resource sandy://skills/cli/resources/scripting-guide.md
This guide defines runtime constraints, available AWS SDK packages, and the required async generator pattern.
IMDS port
Start an IMDS server separately and pass its port to sandy run and sandy check connect.
CLI commands
sandy image
Create, delete, or describe the Sandy sandbox image.
sandy image create
sandy image delete
sandy image delete --force
sandy image current
sandy image current prints the Sandy version that built the image and its creation time. Versions missing from older images print (unknown). Docker backend only.
sandy session create
Create a session and print the session name plus scripts path.
sandy session create
sandy check
Verify sandbox health. Each check creates and deletes an ephemeral session; no session argument is accepted.
sandy check baseline
sandy check connect --imds-port 9001
sandy check connect --imds-port 9001 --region ap-southeast-2
sandy run
Run a TypeScript script from <session>/scripts/.
sandy run --session happy-fox-trail --script inventory.ts --imds-port 9001
sandy run --session happy-fox-trail --script inventory.ts --imds-port 9001 --region ap-southeast-2
sandy run --session happy-fox-trail --script inventory.ts --imds-port 9001 -- arg1 arg2
Options:
| Flag | Required | Description |
|---|---|---|
--session |
yes | Session name |
--script |
yes | Script path relative to <session>/scripts/ |
--imds-port |
yes | Port of the running IMDS server |
--region |
no | AWS region (default us-west-2) |
-- |
no | Arguments passed as process.argv inside the script |
What ships with it
4 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.
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.
- 7d ago Changed · +3 lines f87c51339682
- 1mo ago First seen · 189 lines · 45 tokens per session scan A 496a783f889a
sandy is a skill published in the GitHub repository jamestelfer/sandy (7 stars, last pushed yesterday), licensed Apache-2.0. It adds 45 tokens to every session and 1,743 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-08-31.
Other skills, from other repositories
reinvent-stack-toolkit
Technical patterns and known-only-by-live-invocation pitfalls for the reinvent agent's fixed stack. Covers how to wire services correctly; says nothing about what to build. Read this BEFORE writing any code for a new project on this stack. Only fall back to live AWS docs search when a value here looks stale or the…
aws-cdk
AWS CDK infrastructure development in TypeScript. Use when creating stacks, constructs, L2/L3 patterns, CDK testing, synth/deploy pipelines or organizing IaC code.
aws-lambda-python
AWS Lambda development with Python. Use when writing Lambda handlers, packaging with layers, using boto3/Powertools, structured logging or optimizing Python Lambda performance.
aws-serverless
Building production-ready serverless applications on AWS. Use when working with Lambda, API Gateway, SQS, SNS, DynamoDB Streams, SAM/CDK deployment or optimizing cold starts.
aws-terraform
AWS infrastructure with Terraform. Use when creating modules, managing remote state, writing tftest.hcl tests, refactoring IaC or following HashiCorp style guide.
aws-architecture
AWS architecture decisions, serverless patterns, event-driven design, service boundaries and Well-Architected Framework. Use when designing system architecture or making infrastructure tradeoffs.