developing-with-flutter

developing-with-flutter is a skill for Claude Code, Codex from FortiumPartners/ensemble. It costs 37 tokens per session (2,990 once invoked), scanned B, original, MIT.

A skill for building Flutter applications for iOS, Android, web, and desktop from a shared Dart codebase. Flutter is Google's toolkit for creating user interfaces that run on multiple platforms.

In plain words
What is it for?
Use it to create Flutter projects, design widgets, manage app state, connect platform-specific features, run tests, and prepare multi-platform builds.
Why use it?
It helps avoid platform-specific mistakes in project setup, widgets, navigation, state management, builds, and automated tests.

Skill for Claude CodeCodex

Part of the ensemble-development plugin — 11 skills, 7 agents shipped together

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/fortiumpartners/ensemble/developing-with-flutter
Any agent
npx skills add FortiumPartners/ensemble --skill developing-with-flutter
Clone the repo
git clone --depth 1 https://github.com/FortiumPartners/ensemble

Made for: Claude Code, Codex.

Or install ensemble-development, the plugin that ships this one along with the rest of its 11 skills, 7 agents.

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 developing-with-flutter

README.md
[![agentmods](https://agentmods.dev/badge/skills/fortiumpartners/ensemble/developing-with-flutter.svg)](https://agentmods.dev/skills/fortiumpartners/ensemble/developing-with-flutter)
Your own site
<a href="https://agentmods.dev/skills/fortiumpartners/ensemble/developing-with-flutter"><img src="https://agentmods.dev/badge/skills/fortiumpartners/ensemble/developing-with-flutter.svg" alt="Measured on agentmods" height="20"></a>
Per session 37 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,990 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 1 finding. 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 $0.00037 $0.02990
Opus 5 $0.00018 $0.01495
Sonnet 5 $0.00007 $0.00598
Haiku 4.5 $0.00004 $0.00299

Measured yesterday against content hash 2a2d303100c8, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade B, and why

developing-with-flutter scanned grade B with 1 finding 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.

Asks for rootmediumPrivilege escalation

A mod that escalates privileges can change anything on the machine, not only the project.

| `CocoaPods not installed` | `sudo gem install cocoapods` |
packages/development/skills/developing-with-flutter/SKILL.md · 473 lines

How it starts

The opening of the file, as written. The whole thing — 473 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Flutter SDK Skill

Quick Reference

Flutter is Google's UI toolkit for building natively compiled applications for mobile (iOS, Android), web, and desktop from a single Dart codebase.


Table of Contents

  1. Critical: Avoiding Interactive Mode
  2. Prerequisites
  3. CLI Decision Tree
  4. Project Structure
  5. State Management
  6. Widget Patterns
  7. Navigation (GoRouter)
  8. Platform-Specific Code
  9. Web-Specific Considerations
  10. Testing
  11. Error Handling
  12. CI/CD Integration
  13. Auto-Detection Triggers
  14. Agent Integration
  15. Sources

Critical: Avoiding Interactive Mode

Flutter CLI can enter interactive mode which will hang Claude Code. Always use flags to bypass prompts:

Command WRONG (Interactive) CORRECT (Non-Interactive)
Create project flutter create (prompts) flutter create my_app --org com.example
Run app flutter run (prompts for device) flutter run -d <device_id>
Build flutter build (may prompt) flutter build apk --release
Emulators flutter emulators --launch flutter emulators --launch <emulator_id>

Always include:

  • -d <device_id> for device selection (use flutter devices to list)
  • Explicit build targets (apk, appbundle, ios, web)
  • --no-pub when pub get is not needed
  • --suppress-analytics in CI/CD environments

Never use in Claude Code:

  • Commands that open GUI (Android Studio, Xcode)
  • Interactive device selection prompts
  • Commands without explicit targets

Prerequisites

flutter --version          # Expected: Flutter 3.x.x
flutter doctor             # Check all requirements
flutter devices            # List available devices
flutter emulators          # List available emulators

Read the full file on GitHub · 473 lines

Files

What ships with it

3 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. yesterday First seen · 473 lines · 37 tokens per session scan B 2a2d303100c8

Subscribe to this mod's changes

developing-with-flutter is a skill published in the GitHub repository FortiumPartners/ensemble (11 stars, last pushed 1mo ago), licensed MIT. It adds 37 tokens to every session and 2,990 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it B with 1 finding (asks for root). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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