standard-rest-api-endpoint-design

A set of conventions for designing REST API endpoints, which are URLs that let software perform operations on data. It recommends routes that clearly represent the business action being performed.

In plain words
What is it for?
Use it when choosing route structures, separating actions such as accepting or rejecting an item, and deciding which parent resource IDs belong in a URL.
Why use it?
It makes APIs easier to predict and understand by avoiding overloaded endpoints and routes that contain unrelated resource identifiers.

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/packmindhub/packmind/standard-rest-api-endpoint-design
Clone the repo
git clone --depth 1 https://github.com/PackmindHub/packmind

Made for: Cursor.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 161 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 $0.00000 $0.00161
Opus 5 $0.00000 $0.00081
Sonnet 5 $0.00000 $0.00032
Haiku 4.5 $0.00000 $0.00016

Measured 2d ago against content hash 8e7cc04f8139, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

standard-rest-api-endpoint-design 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.

apps/api/.cursor/rules/packmind/standard-rest-api-endpoint-design.mdc · 12 lines

What it actually says

Standard: REST API Endpoint Design

Conventions for designing REST API endpoints that are predictable, self-documenting, and aligned with distinct business actions. Favors dedicated action endpoints over generic status updates, and rout... :

  • Create one endpoint per business action rather than a single endpoint handling multiple actions via request body
  • Only include resource IDs from the ownership chain in the route — omit IDs of related but non-parent resources
  • Use dedicated POST action endpoints (e.g., /reject, /accept) instead of a generic PATCH with a status field in the body

Full standard is available here for further request: REST API Endpoint Design

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 · 12 lines · 0 tokens per session scan A 8e7cc04f8139

Subscribe to this mod's changes

standard-rest-api-endpoint-design is a cursor rule published in the GitHub repository PackmindHub/packmind (306 stars, last pushed 5d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 161 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 2026-08-30.