20-routing

A routing rule that keeps all website URL definitions in one file, app/routes.ts. Each URL is explicitly linked to the code that displays it.

In plain words
What is it for?
Use it when organizing or reviewing routes in a Hydrogen storefront, including page URLs and separate files such as robots.txt or sitemap.xml.
Why use it?
It prevents routes from being duplicated or discovered indirectly, which makes navigation harder to understand and maintain.

Cursor rule for Cursor

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 rules/commerce-atoms/agents/20-routing
Clone the repo
git clone --depth 1 https://github.com/commerce-atoms/agents

Made for: Cursor.

Per session 205 This file is loaded in full into every session.
When invoked 205 The same file — it is already loaded in full.
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 $0.00205 $0.00205
Opus 5 $0.00102 $0.00102
Sonnet 5 $0.00041 $0.00041
Haiku 4.5 $0.00020 $0.00020

Measured 2d ago against content hash 35e09e0347c9, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

20-routing 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 2d 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.

kit/.cursor/rules/20-routing.mdc · 29 lines

What it actually says

This is a Cursor-specific overlay. Canonical source: rules/core/routing.md.

Single source of truth

  • app/routes.ts is the only routing manifest.
  • Do not add additional route manifest files.
  • Do not add a second routing entrypoint that duplicates routing definitions.

No filesystem routing

  • Do not rely on app/routes/* filesystem discovery as the routing source of truth.

Explicit mapping

  • Each URL pattern maps explicitly to a route module file under app/modules/*.
  • Avoid abstractions that generate, auto-compose, or implicitly register routes.

Layout nesting

  • UI routes are nested under the layout shell route (owned by app/layout/*).
  • Resource routes (robots.txt, sitemap.xml, etc.) remain outside layout nesting.
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. 2d ago First seen · 29 lines · 205 tokens per session scan A 35e09e0347c9

Subscribe to this mod's changes

20-routing is a cursor rule published in the GitHub repository commerce-atoms/agents (1 stars, last pushed 4mo ago), licensed MIT. It adds 205 tokens to every session, about $0.0010 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 2026-08-31.