.NET MAUI is a C# and XAML framework for building native mobile and desktop applications from one shared codebase. Developers use it to create apps for Android, iOS, iPadOS, macOS, and Windows. The catalogue entries provide skills, instructions, and agents for working with .NET MAUI.
Borrowing it
Nothing to install: this file belongs to dotnet/maui. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/dotnet/maui/main/.github/instructions/sandbox.instructions.mdgit clone --depth 1 https://github.com/dotnet/mauiWrote 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.
[](https://agentmods.dev/instructions/dotnet/maui/sandbox)<a href="https://agentmods.dev/instructions/dotnet/maui/sandbox"><img src="https://agentmods.dev/badge/instructions/dotnet/maui/sandbox/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/instructions/dotnet/maui/sandbox"><img src="https://agentmods.dev/badge/instructions/dotnet/maui/sandbox.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.07693 | $0.07693 |
| Opus 5.5 | $0.03077 | $0.03077 |
| Sonnet 5.5 | $0.01539 | $0.01539 |
| Haiku 4.5 | $0.00769 | $0.00769 |
Grade C, and why
maui sandbox.instructions.md scanned grade C 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 1mo 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.
Recursive force deletehighDestructive command
rm -rf with a variable or a broad path is one typo away from removing the wrong tree.
rm -rf CustomAgentLogsTmp/Sandbox/ How it starts
The opening of the file, as written. The whole thing — 820 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Sandbox Testing Guide
Comprehensive guide for working with the .NET MAUI Sandbox app for manual testing, PR validation, issue reproduction, and experimentation with MAUI features.
When This Applies
This guide applies when you:
- Work with files in
src/Controls/samples/Controls.Sample.Sandbox/ - User asks to "test this PR" or "validate PR #XXXXX" in Sandbox
- User asks to "reproduce issue #XXXXX" in Sandbox
- User wants to deploy to iOS/Android for manual testing
- User mentions Sandbox app by name in testing context
🚨 CRITICAL VALIDATION RULES - READ FIRST
YOU MUST FOLLOW THESE RULES WHEN RUNNING SANDBOX TESTS:
What You NEVER Do (Absolute Rules)
- ❌ NEVER assume test completion without validation
- ❌ NEVER claim success based on HTTP 200 responses alone (element found ≠ test completed)
- ❌ NEVER skip the mandatory validation checklist
- ❌ NEVER proceed without verifying device logs show expected behavior
- ❌ NEVER assume Appium connection means test finished
- ❌ NEVER claim button was tapped without checking device logs
- ❌ NEVER switch branches (e.g.,
git checkout main) during reproduction - stay on current branch
What You ALWAYS Do (Mandatory Steps)
- ✅ ALWAYS save full output to file for analysis
- ✅ ALWAYS check for errors/exceptions FIRST before claiming success
- ✅ ALWAYS verify "Test completed" marker appears in output
- ✅ ALWAYS verify expected test actions in logs (Tapping, Screenshot, etc.)
- ✅ ALWAYS check device logs for Console.WriteLine markers (e.g., "SANDBOX: ...")
- ✅ ALWAYS verify artifacts exist (screenshots, if test captures them)
Rule 1: NEVER ASSUME TEST COMPLETION
- ❌ DO NOT assume the test completed successfully just because Appium connected
- ❌ DO NOT assume success based on HTTP 200 responses (element found ≠ test completed)
- ✅ DO verify test completion by checking for completion markers in output
- ✅ DO search for "Test completed", "═══════", or final summary messages
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.
- 1mo ago First seen · 820 lines · 7,693 tokens per session scan C d4726bba73de
maui sandbox.instructions.md is an instructions file published in the GitHub repository dotnet/maui (23,322 stars, last pushed today), licensed MIT. It adds 7,693 tokens to every session, about $0.0308 per session on Opus 5.5. A static security scan graded it C with 1 finding (recursive force delete). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
deepseek-harness AGENTS.md
AGENTS.md instructions for deepseek-ai/deepseek-harness, covering agents.md, pre-stable apis and released session data, repository layout, commands and host sandbox failures.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).