Show HN: Testmagic.link – Zero-setup magic link testing for coding agents

A developer launched Testmagic.link, a zero-setup email testing service for coding agents, after Claude Code repeatedly used his personal Gmail for magic-link authentication tests. The service requires no signup, API keys, or integration, and includes an optional mail-scanner simulation via ?prefetch=1 to catch flows broken by security scanners. The tool is available at testmagic.link.

I built testmagic.link because Claude Code kept using my personal Gmail when testing magic-link authentication, filling my inbox with test emails. I know there are existing email testing services, but the ones I found require signing up, getting credentials, and integrating an API. That felt like overkill when I just wanted to tell Claude Code: "test the email sign-in using testmagic.link". So I made testmagic.link. No signup, no API keys, no integration. It’s basically a one-liner with a domain that’s easy to remember. I also added an llms.txt file at the root, so agents instantly know how to read the inbox without me explaining it. There’s also an optional mail-scanner simulation: add ?prefetch=1 to the inbox URL, and testmagic.link will GET each message’s magic link once before you open it, without following redirects — similar to how Outlook Safe Links or a corporate mail scanner might prefetch links. This is useful for catching magic-link flows that break when a security scanner visits a single-use link first. Would love to hear your feedback, or if you've run into any other weird email auth edge cases I should simulate. I'll be around to answer questions Comments URL: https://news.ycombinator.com/item?id=49374124 https://news.ycombinator.com/item?id=49374124 Points: 1 Comments: 0