shard

shard is a skill for Claude Code, Codex from simota/agent-skills. It costs 39 tokens per session (3,929 once invoked), scanned A, original, MIT.

A design helper for SaaS applications that serve multiple customers from one system. It covers how each customer’s data is isolated, how requests are routed, and how the system grows safely.

In plain words
What is it for?
Use it to design database isolation and row-level security, customer routing, protection against noisy neighbors, onboarding, usage billing, and migration from separate customer systems.
Why use it?
Shared customer systems can accidentally expose one customer’s data to another or let one customer consume too many resources. It turns those risks into concrete architecture and migration plans.

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/simota/agent-skills/shard
Any agent
npx skills add simota/agent-skills --skill shard
Clone the repo
git clone --depth 1 https://github.com/simota/agent-skills

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 shard

README.md
[![agentmods](https://agentmods.dev/badge/skills/simota/agent-skills/shard.svg)](https://agentmods.dev/skills/simota/agent-skills/shard)
Your own site
<a href="https://agentmods.dev/skills/simota/agent-skills/shard"><img src="https://agentmods.dev/badge/skills/simota/agent-skills/shard.svg" alt="Measured on agentmods" height="20"></a>
Per session 39 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,929 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 5.1 $0.00039 $0.03929
Opus 5 $0.00019 $0.01965
Sonnet 5 $0.00008 $0.00786
Haiku 4.5 $0.00004 $0.00393

Measured 5d ago against content hash acce13c8d90f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

shard 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.

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.

.archive/shard/SKILL.md · 241 lines

How it starts

The opening of the file, as written. The whole thing — 241 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Shard

Design multi-tenant architectures. Shard turns SaaS requirements into tenant isolation strategies, RLS policies, routing designs, noisy-neighbor protections, and migration plans.

Trigger Guidance

Use Shard when the user needs:

  • a tenant isolation strategy designed (DB/schema/row-level)
  • Row Level Security (RLS) policies designed
  • tenant routing implemented (subdomain, header, path)
  • noisy neighbor protection designed
  • single-tenant to multi-tenant migration planned
  • tenant onboarding/provisioning automated
  • cross-tenant data leakage risk assessed
  • tenant billing and usage metering designed

Read the full file on GitHub · 241 lines

Files

What ships with it

8 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 · 241 lines · 39 tokens per session scan A acce13c8d90f

Subscribe to this mod's changes

shard is a skill published in the GitHub repository simota/agent-skills (75 stars, last pushed 3d ago), licensed MIT. It adds 39 tokens to every session and 3,929 once invoked, about $0.0002 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.