Claude Code技巧：用Opus 5.5审查邮件发送配置

Claude Code tip: if your vibe-coded app sends any email, have Opus 5.5 send out 𝟰 𝘀𝘂𝗯𝗮𝗴𝗲𝗻𝘁𝘀 before you ship to check 𝘁𝗵𝗲𝘀𝗲 𝟭𝟱 𝘁𝗵𝗶𝗻𝗴𝘀, then fix them all in one pass:

Sending setup → Still sending sign-up codes and password resets through Supabase's built-in email? It only delivers to your team members, 2 messages an hour. Switch to a sending service on your own domain → Send from your own domain, not a free Gmail address, and set Reply-To to an inbox someone actually reads → Set up SPF, DKIM and DMARC, aligned with your sending domain → Send marketing email and notifications like sign-up codes from different addresses or subdomains, so complaints about marketing drag down your codes less

Login and codes → Opening a login, verification or reset link shouldn't use it up. Make the user click a button on the page, or just send a 6-digit code. Company mail scanners click the link before the user does → Hook up your sending service's bounce and complaint webhooks: stop sending to hard bounces and complaints, stop after repeated soft bounces too, and don't resend codes that have already expired

Bulk mail and unsubscribes → Put one-click unsubscribe (List-Unsubscribe and List-Unsubscribe-Post) on marketing email and honor it within 2 days. It's mandatory if you send Gmail more than 5,000 a day → Ramp up a new domain on a schedule. Don't blast your whole list on day one → Block disposable addresses, typo'd domains (gmial instead of gmail) and domains with no MX record before they reach your list → Watch your complaint rate in Gmail's Postmaster Tools. Keep it under 0.1%. Around 0.3%, your mail is likely to get rejected → Apple Mail loads images automatically, which inflates opens. Company security scanners click links automatically, which inflates clicks. Take both out of your stats

The email itself → Build the HTML with tables and inline styles so it holds up in Outlook → Keep the HTML code under 102KB (images don't count). Over that, Gmail clips the rest, and the unsubscribe link at the bottom disappears with it → Include a plain-text version with every email → Preview variables like first name with a fake subscriber, so you never send "Hi {first_name}"

The default medium effort is enough. The login and codes group has to read your sending and webhook code, so raise that one to high.

Send this whole post to Claude Code. If you need to, add this line at the end 👇 "Send one subagent per group to check it without editing anything, and note which file or dashboard each issue is in. Run the login and codes subagent at high effort. For the email service key, report only where it is and never paste its value. Only send test emails to my own test inbox, and don't call any bulk-send endpoint. Send one email to my Gmail, and I'll paste you the SPF, DKIM and DMARC lines from 'Show original'. For DNS, Postmaster Tools and the sending service's dashboard, give me the steps and I'll do them myself. Show me the list of issues first, don't change anything until I confirm, and when you're done, give me a pass/fail table."