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April 15, 2026Claude Skills Hub

claude prompt for email subject lines

## Crafting Compelling Email Subject Lines with Claude You're trying to write email subject lines that grab attention and drive opens, but your current app

claudepromptsemailsubjectlines

Crafting Compelling Email Subject Lines with Claude

You're trying to write email subject lines that grab attention and drive opens, but your current approach is yielding lackluster results. You've tried brainstorming lists of keywords, using vague phrases, and even resorting to clickbait tactics, but nothing seems to be working. The problem is that your subject lines are getting lost in crowded inboxes, and you're struggling to stand out from the competition.

The key to writing effective email subject lines is to use a combination of creativity and structure. This is where Claude's prompt codes come in. By stacking PERSONA and /hook codes, you can generate subject lines that are both personalized and attention-grabbing. The PERSONA code helps you understand your target audience and tailor your language to their needs, while the /hook code provides a framework for crafting a compelling and relevant message.

Here's an example of how this works in practice: Before: "Check out our new summer sale" After: "Summer vibes ahead: 20% off your favorite outdoor gear" In the "after" example, we've used the PERSONA code to understand that our target audience is outdoor enthusiasts, and the /hook code to craft a subject line that speaks directly to their interests.

Some people try to use codes like L99 or /skeptic to generate subject lines, but these approaches often fall flat. L99 can produce overly formal and generic language, while /skeptic can come across as too negative or critical. For instance, using L99 might result in a subject line like "Notification: Summer Sale Now Active", which lacks the personal touch and creativity of the "after" example. Similarly, using /skeptic might produce a subject line like "Is this summer sale really worth it?", which can be off-putting and unengaging.

It's also important to note that this approach isn't suitable for every type of email. If you're sending a formal notification or a transactional email, a more straightforward subject line may be more effective. Additionally, if you're targeting a very niche or technical audience, you may need to use more specialized language and codes, such as ARTIFACTS or /deepthink.

To take your email subject line game to the next level, it's essential to experiment with different codes and combinations. You can also use codes like OODA to analyze your audience's needs and preferences, and PARETO to identify the most effective subject line elements. By combining these codes with PERSONA and /hook, you can create subject lines that are both personalized and optimized for maximum impact.

See all 120 codes tested over 3 months in the Cheat Sheet

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160+ prompt patterns, each with the temperature, top_p, and system prompt we actually use, why we picked it, and what breaks when you get it wrong. If a lookup table is what you needed, this is the same thing at 20x the depth.

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