state-management

state-management is a cursor rule for Cursor from kok-o/koko-contextos-agents. It costs 28 tokens per session (1,068 once invoked), scanned A, original, MIT.

A set of rules for managing data in React and Next.js applications, separating temporary interface state from data fetched from a server.

In plain words
What is it for?
Use it when building server-data fetching, cached queries, optimistic updates, modals, filters, wizards, or themes with Zustand and TanStack Query.
Why use it?
It prevents duplicated or misplaced data and helps keep loading, caching, updates, and interface changes predictable.

Cursor rule for Cursor

Written for Cursor: installed under .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/kok-o/koko-contextos-agents/state-management
Clone the repo
git clone --depth 1 https://github.com/kok-o/koko-contextos-agents

Made for: Cursor.

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 state-management

README.md
[![agentmods](https://agentmods.dev/badge/rules/kok-o/koko-contextos-agents/state-management.svg)](https://agentmods.dev/rules/kok-o/koko-contextos-agents/state-management)
Your own site
<a href="https://agentmods.dev/rules/kok-o/koko-contextos-agents/state-management"><img src="https://agentmods.dev/badge/rules/kok-o/koko-contextos-agents/state-management.svg" alt="Measured on agentmods" height="20"></a>
Per session 28 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,068 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 $0.00028 $0.01068
Opus 5 $0.00014 $0.00534
Sonnet 5 $0.00006 $0.00214
Haiku 4.5 $0.00003 $0.00107

Measured 6d ago against content hash 1c493ba080d1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

state-management 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 6d 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.

.cursor/rules/state-management.mdc · 129 lines

How it starts

The opening of the file, as written. The whole thing — 129 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Skill: state-management

State Management

Overview

Global client state and server state management in modern React and Next.js applications using Zustand and TanStack Query.

When to Use

Activate when managing asynchronous server data fetching/caching, optimistic UI updates, or global UI client state (modals, filters, wizards).

Rules & Patterns

The Rule of Two States

  • SERVER STATE (Async): Managed exclusively by TanStack Query (useQuery, useMutation). Caching, background refetching, pagination, and invalidation.
  • CLIENT STATE (Sync): Managed by Zustand. Modal visibility, active filters, wizard step, theme.

Negative Constraints (What NOT to Do)

  1. NEVER store server-fetched data in Zustand or Redux stores: Store ONLY client-local UI state in Zustand. All API data belongs in TanStack Query.
  2. NEVER duplicate derived state: Compute values inline or via useMemo from existing state instead of storing redundant state variables.
  3. NEVER subscribe to entire store objects in components: Always use atomic selector functions (e.g. useStore(state => state.isOpen)) to prevent unnecessary component re-renders.
  4. NEVER mutate state directly: Always return new immutable state objects in Zustand setters.
  5. NEVER ignore optimistic rollback on mutation failure: When implementing optimistic UI, always capture previousData in onMutate and restore it in onError.

Code Examples

See EXAMPLES.md for Zustand store patterns and optimistic TanStack mutations.

Validation Checklist

  • Clear separation between Server (TanStack Query) and Client (Zustand) state
  • Atomic selectors used on all Zustand hook calls
  • Optimistic updates implement rollback on error
  • Zero duplicated derived state

Common Mistakes

  • Subscribing to full store objects causing cascading re-renders. See TROUBLESHOOTING.md.

Integration Notes

Interacts with react, nextjs, and typescript.

State Management Examples — Anti-patterns vs ContextOS Standard

Read the full file on GitHub · 129 lines

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. 6d ago First seen · 129 lines · 28 tokens per session scan A 1c493ba080d1

Subscribe to this mod's changes

state-management is a cursor rule published in the GitHub repository kok-o/koko-contextos-agents (2 stars, last pushed 2d ago), licensed MIT. It adds 28 tokens to every session and 1,068 once invoked, about $0.0001 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.

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