cursorrules

A set of Flutter coding rules covering project structure, Material 3, BLoC, dependency injection, error handling, localization, and platform conventions.

In plain words
What is it for?
Use it when building or reviewing Flutter application code and its organization.
Why use it?
It gives the agent project guidance while allowing it to follow an existing architecture instead of forcing a fixed layout.

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/ricardocaste/flutter-cursor-rules/cursorrules
Clone the repo
git clone --depth 1 https://github.com/ricardocaste/flutter-cursor-rules

Made for: Cursor.

Per session 589 This file is loaded in full into every session.
When invoked 589 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin 88% copy Near-identical to another mod 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 $0.00589 $0.00589
Opus 5 $0.00295 $0.00295
Sonnet 5 $0.00118 $0.00118
Haiku 4.5 $0.00059 $0.00059

Measured yesterday against content hash 992032ec331d, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

cursorrules 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 yesterday.

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.

Origin

This is a copy

88% identical to flutter-app-expert-cursorrules-prompt-file — 50 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.cursorrules · 111 lines

What it actually says

// Flutter App Expert .cursorrules

// Flexibility Notice

// Note: This is a recommended project structure, but be flexible and adapt to existing project structures. // Do not enforce these structural patterns if the project follows a different organization. // Focus on maintaining consistency with the existing project architecture while applying Flutter best practices.

// Flutter Best Practices

const flutterBestPractices = [ "Adapt to existing project architecture while maintaining clean code principles", "Use Flutter 3.x features and Material 3 design", "Implement clean architecture with BLoC pattern, in particular with Cubit", "Follow proper state management principles", "Use proper dependency injection", "Implement proper error handling", "Follow platform-specific design guidelines", "Use proper localization techniques", ];

// Project Structure

// Note: This is a reference structure. Adapt to the project's existing organization

const projectStructure = lib/ data/ datasources/ models/ providers/ repositories/ firebase_options.dart domain/ entities/ repositories/ usecases/ infrastructure/ constants/ di/ errir/ extensions/ network/ services/ usecases/ utils.dart presentation/ bloc/ nav/ pages/ widgets/ themes.dart main.dart test/ unit/ widget/ integration/;

// Coding Guidelines

const codingGuidelines = `

  1. Use proper null safety practices
  2. Implement proper error handling with Either type
  3. Follow proper naming conventions
  4. Use proper widget composition
  5. Implement proper routing using GoRouter
  6. Use proper form validation
  7. Follow proper state management with BLoC, in particular with Cubit
  8. Implement proper dependency injection using GetIt
  9. Use proper asset management
  10. Follow proper testing practices `;

// Widget Guidelines

const widgetGuidelines = `

  1. Keep widgets small and focused
  2. Use const constructors when possible
  3. Implement proper widget keys
  4. Follow proper layout principles
  5. Use proper widget lifecycle methods
  6. Implement proper error boundaries
  7. Use proper performance optimization techniques
  8. Follow proper accessibility guidelines `;

// Performance Guidelines

const performanceGuidelines = `

  1. Use proper image caching
  2. Implement proper list view optimization
  3. Use proper build methods optimization
  4. Follow proper state management patterns
  5. Implement proper memory management
  6. Use proper platform channels when needed
  7. Follow proper compilation optimization techniques `;

// Testing Guidelines

const testingTestingGuidelines = `

  1. Write unit tests for business logic
  2. Implement widget tests for UI components
  3. Use integration tests for feature testing
  4. Implement proper mocking strategies
  5. Use proper test coverage tools
  6. Follow proper test naming conventions
  7. Implement proper CI/CD testing `;
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. yesterday First seen · 111 lines · 589 tokens per session scan A 992032ec331d

Subscribe to this mod's changes

cursorrules is a cursor rule published in the GitHub repository ricardocaste/flutter-cursor-rules (3 stars, last pushed 1y ago), licensed Apache-2.0. It adds 589 tokens to every session, about $0.0029 per session on Opus 5. A static security scan graded it A with 0 findings. It is 88% identical to flutter-app-expert-cursorrules-prompt-file, differing in 50 lines, and is treated as a copy.