A service that gives coding agents disposable email inboxes for testing signups, logins, and email verification.

Use it to register test accounts, retrieve verification codes or magic links, send or reply on approved domains, and investigate email-delivery timeouts.

It avoids manually opening email messages or parsing their HTML to find one-time passwords and login links. It also lets tests receive simulated email without using a real mail server.

mailagent — Skill for Claude Code and Codex by hashgraph-online

About the project

Awesome Codex Plugins is a curated catalogue and marketplace of installable plugins, skills, and related resources for OpenAI Codex and ChatGPT. It helps people find, create, validate, and submit extensions for Codex workflows across its app, command-line interface, and IDE extensions. The catalogue add-ons are the plugins, skills, agents, and hooks listed or supported by this project.

hashgraph-online/awesome-codex-plugins · 1,346 stars · on GitHub · hol.org

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.

Any agent

npx skills add hashgraph-online/awesome-codex-plugins --skill mailagent

Clone the repo

git clone --depth 1 https://github.com/hashgraph-online/awesome-codex-plugins

Made for: Claude Code, Codex.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/hashgraph-online/awesome-codex-plugins/mailagent/github.svg)](https://agentmods.dev/skills/hashgraph-online/awesome-codex-plugins/mailagent)

Your own site

<a href="https://agentmods.dev/skills/hashgraph-online/awesome-codex-plugins/mailagent"><img src="https://agentmods.dev/badge/skills/hashgraph-online/awesome-codex-plugins/mailagent/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/hashgraph-online/awesome-codex-plugins/mailagent"><img src="https://agentmods.dev/badge/skills/hashgraph-online/awesome-codex-plugins/mailagent.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 3,323 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. Third-party audits

NVIDIA SkillSpector warn 7 Sept 2026

SkillSpector: 4 findings, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

high YARA Match · line 223
YARA rule matched a hack tool or exploit indicator (offensive tools, reconnaissance, privilege escalation, or exploit frameworks).

Fix: Remove offensive tool references and exploit code. Legitimate agent skills should not contain penetration testing tools, exploit frameworks, or reconnaissance utilities.
medium MCP Rug Pull · line 40
npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.

Fix: Pin the version: npx @scope/[email protected]
medium Data Exfiltration · line 60
Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
medium Data Exfiltration · line 170
Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.

How audits are shown

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.

Model	Per session	Once invoked
Fable 5.1	$0.00043	$0.03323
Opus 5.5	$0.00017	$0.01329
Sonnet 5.5	$0.00009	$0.00665
Haiku 4.5	$0.00004	$0.00332

Measured 1mo ago against content hash 342745ffa80e, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

mailagent 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 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.

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.

plugins/Alex0nder/MailAgent/skills/mailagent/SKILL.md · 257 lines

How it starts

The opening of the file, as written. The whole thing — 257 lines — stays where its author put it; the contents beside it link to each section on GitHub.

MailAgent

MailAgent provides programmatic disposable inboxes for AI agents: receive OTP codes and magic links during signup flows, simulate inbound mail in CI, send/reply on verified domains, and diagnose timeouts.

Official docs: https://webmailagent.com/docs/agents.html

When to use

Signup or login that sends a verification email
Need OTP or magic link without hand-parsing HTML
E2E / agent task: "register with a temp email"
QA without real SMTP (mailagent_simulate_message)
Not for human privacy burners — programmatic agent inboxes with allowlists

Install (pick one)

Cursor (project)

MCP in .cursor/mcp.json → @mailagent/mcp or mcp/dist/index.js. Skill auto-loads from .cursor/skills/mailagent-mcp/ (synced from this file).

Agent Skills catalog (repo root)

npx skills add Alex0nder/MailAgent --skill mailagent

OpenAI Codex

codex plugin marketplace add Alex0nder/MailAgent
codex plugin add mailagent@mailagent

Guide: https://webmailagent.com/docs/codex.html

npm MCP (any client)

export MAILAGENT_API_URL=https://api.webmailagent.com
export MAILAGENT_API_KEY=ma_…
npx -y -p @mailagent/[email protected] mailagent-mcp

Remote (no subprocess): POST https://api.webmailagent.com/mcp + Bearer token.

SDK (without MCP)

Package	Install
`@mailagent/agent`	`npm install @mailagent/agent`
`@mailagent/qa`	`npm install @mailagent/qa` (Playwright)
`mailagent-agent`	`pip install mailagent-agent` (Python)

Browser login (no API key in client): Auth0 OIDC on prod — auth.oidc: enabled on GET /v1/agent. Operator setup: npm run wizard:auth0. Docs: https://webmailagent.com/docs/oauth-idp.html

Prerequisites

MAILAGENT_API_KEY — console dashboard team keys, or MailAgent repo npm run issue:key:db when self-hosting
MCP server mailagent connected (codex mcp list / Cursor MCP refresh)
Always set service preset or expectFrom (sender allowlist)

Read the full file on GitHub · 257 lines

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.

1mo ago First seen · 257 lines · 43 tokens per session scan A 342745ffa80e

Subscribe to this mod's changes

mailagent is a skill published in the GitHub repository hashgraph-online/awesome-codex-plugins (1,346 stars, last pushed yesterday), licensed Apache-2.0. It adds 43 tokens to every session and 3,323 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-08-30.

E2E testing Testing ai-coding awesome awesome-list codex codex-plugins openai

e2e-testing

Guide for running end-to-end tests of the Qwen Code CLI, including headless mode, MCP server testing, and API traffic inspection. Use this skill whenever you need to verify CLI behavior with real model calls, reproduce user-reported bugs end-to-end, test MCP tool integrations, or inspect raw API request/response…

QwenLM/qwen-code · 94 tokens

terminal-capture

Automates terminal UI screenshot testing for CLI commands. Applies when reviewing PRs that affect CLI output, testing slash commands (/about, /context, /auth, /export), generating visual documentation, or when 'terminal screenshot', 'CLI test', 'visual test', or 'terminal-capture' is mentioned.

QwenLM/qwen-code · 66 tokens

agent-reproduce-align

Use after a Codex or Claude Code feature has been implemented in Qwen Code to run the selected reference agent and Qwen Code under the same scenario, capture HTTP and terminal traces, compare request bodies, tool/function schemas, outputs, and iterate until the reproduced behavior is close enough.

QwenLM/qwen-code · 62 tokens

mailagent