Overview
What It Does
Testing With Sandbox packages a focused communication workflow for an AI agent. Use when capturing outbound email in development or staging without delivering to real recipients, inspecting HTML or headers, running spam or structure checks, or automating tests against a fake inbox. Use when testing outgoing mail from an app without committing to a production ESP yet. Use when using Mailtrap Email Sandbox, Sandbox API, or sandbox-mode sending. It is best suited to users who can review the resulting actions and provide only the accounts, files, or command access needed for the task. It is not a substitute for human approval on destructive, financial, security-sensitive, or public-facing actions.
Task ideas
Popular Use Cases
- Draft and organize messages
- Work with communication channels and contacts
- Summarize conversations into next steps
- Automate routine coordination
Installation
Install this Agent Skill
Claude Code
npx skills add https://github.com/mailtrap/mailtrap-skills --skill testing-with-sandboxCommands derived from the public GitHub SKILL.md record. Checked 2026-09-02. Review the source before running them.
Before you start
Requirements
| Claude Code | Required / review |
| Codex | Required / review |
| Public SKILL.md source | Required / review |
| Review instructions and requested permissions before installation | Required / review |
| Paid service | Check source |
| Supported system | Check source |
Popularity context
Why It’s Popular
Testing With Sandbox is a verified Agent Skill from mailtrap with a public SKILL.md, compatible with Claude Code, Codex.
Alternatives
