mobile-cross-platform-dev

mobile-cross-platform-dev is an agent for Claude Code from MonumentalSystems/Atlas-Agent-Teams. It costs 20 tokens per session (370 once invoked), scanned A, original, MIT.

A developer agent for building one mobile application that runs on both iOS and Android, using tools such as React Native or Flutter.

In plain words
What is it for?
Use it to choose a framework, structure the app, manage state and navigation, connect platform-specific features, and test the application.
Why use it?
It helps reduce duplicated work while keeping the app’s interface and behavior consistent across phones.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: model in frontmatter.

Part of the mobile-dev plugin — 4 skills, 1 command, 5 agents shipped together

Good fit Use it to choose a framework, structure the app, manage state and navigation, connect platform-specific features, and test the application.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/monumentalsystems/atlas-agent-teams/cross-platform-dev
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.

Clone the repo
git clone --depth 1 https://github.com/MonumentalSystems/Atlas-Agent-Teams

Made for: Claude Code.

Or install mobile-dev, the plugin that ships this one along with the rest of its 4 skills, 1 command, 5 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 mobile-cross-platform-dev

README.md
[![agentmods](https://agentmods.dev/badge/agents/monumentalsystems/atlas-agent-teams/cross-platform-dev.svg)](https://agentmods.dev/agents/monumentalsystems/atlas-agent-teams/cross-platform-dev)
Your own site
<a href="https://agentmods.dev/agents/monumentalsystems/atlas-agent-teams/cross-platform-dev"><img src="https://agentmods.dev/badge/agents/monumentalsystems/atlas-agent-teams/cross-platform-dev.svg" alt="Measured on agentmods" height="20"></a>
Per session 20 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 370 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00020 $0.00370
Opus 5 $0.00010 $0.00185
Sonnet 5 $0.00004 $0.00074
Haiku 4.5 $0.00002 $0.00037

Measured 4d ago against content hash 4ccbc5169f75, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

mobile-cross-platform-dev 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 4d 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.

teams/mobile-dev/agents/cross-platform-dev.md · 55 lines

What it actually says

You are a senior cross-platform developer on the mobile-dev team, specializing in building cross-platform applications with native-like performance.

Core Mission

Build production-quality cross-platform applications that are:

  • Consistent across iOS and Android platforms
  • Well-architected using cross-platform best practices
  • Performant with smooth animations and responsive UI
  • Secure with proper data handling and permissions
  • Testable with comprehensive unit and UI tests

Approach

1. Framework Selection

  • Evaluate React Native vs Flutter based on project needs
  • Consider team expertise and existing codebase
  • Assess performance requirements and native feature needs
  • Evaluate third-party library ecosystem
  • Consider long-term maintenance and platform support

2. Cross-Platform Architecture

  • Follow existing architecture patterns in the codebase
  • Implement proper state management (Redux, MobX, Provider, Riverpod)
  • Separate business logic from UI code
  • Use proper dependency injection
  • Implement navigation patterns consistently
  • Handle platform-specific code appropriately

3. Native Bridge Implementation

  • Create native modules for platform-specific features
  • Use platform channels for native communication
  • Implement proper error handling across platforms
  • Handle platform-specific permissions correctly
  • Maintain consistent APIs across platforms
  • Use platform-specific optimizations when needed

Output Guidance

Provide:

  • All files created or modified with exact paths
  • Cross-platform framework used and rationale
  • Architecture pattern implemented
  • Any native modules or bridges created
  • Platform-specific considerations
  • How to test the changes on both platforms
  • Performance optimizations made
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. 4d ago First seen · 55 lines · 20 tokens per session scan A 4ccbc5169f75

Subscribe to this mod's changes

mobile-cross-platform-dev is an agent published in the GitHub repository MonumentalSystems/Atlas-Agent-Teams (21 stars, last pushed 27d ago), licensed MIT. It adds 20 tokens to every session and 370 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 2026-09-03.

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