# Email Design > Design distinctive, on-brand emails — newsletters, campaigns, welcome series, promo, post-purchase, win-back, transactional, announcements. Use when the user wants to draft, write, compose, design, redesign, critique, polish, or improve an email; or send a campaign / blast / broadcast through any ESP (Nitrosend, Klaviyo, Mailchimp, ActiveCampaign, etc.). Produces a structured design brief and translates it into the sending tool's section format. Bakes in anti-slop principles: own a colour, restrained palettes, real imagery with sourced or prompted image slots, distinctive voice, no category-reflex aesthetics, no orphan whitespace, single column ≤600px, mobile-first, real footers (verified mission only, plus socials + address + unsubscribe). Asks at most three questions to fill brand gaps; otherwise infers from connected ESP account settings or a project brand file. Self-contained — no other skills required. Skip for pure strategy, deliverability, copy-only, or platform-selection questions. - Skill: `cosmoblk/email-design` (Agent Skill, multi-file: 4 files) - Install (CLI): `npx skillmds@latest add cosmoblk/email-design` - Raw SKILL.md: https://api.skillmd.com/api/skills/cosmoblk/email-design/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Marketing & Growth - License: MIT - Author: cosmoblk (https://skillmd.com/u/cosmoblk) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/cosmoblk/email-design --- # Email Design Skill Distinctive, on-brand emails. Produces a structured brief, then hands it to the connected sending tool. Self-contained. ## When to use Triggered for: - "draft / write / compose / design / build an email" (newsletter, campaign, blast, broadcast, announcement, welcome, win-back, post-purchase, abandoned cart, promo, transactional) - "make this email less generic / less plain / more on brand" - "redesign / critique / polish this email" - "send a campaign through Nitrosend / Klaviyo / etc." Skip for: - Strategy-only ("what frequency should I send at?") - Deliverability-only ("why am I in spam?") - Platform selection ("Klaviyo vs Mailchimp?") - Copywriting in isolation, no design ## The flow (five steps) 1. **Context check** — pull brand state from the connected ESP and project files. No questions yet. 2. **Ask up to three questions** — only the highest-leverage gaps. Bundle into one message. 3. **Pick an archetype, write the brief.** Commit before composing. 4. **Resolve image slots** — fetch from brand site, brand assets, or prompt the user. 5. **Translate the brief into the sending tool's format** and run a dry-run preview before approval. --- ## Step 1 — Context check (silent) Pull what is already known. **Do not ask the user yet.** If Nitrosend MCP tools are available (`nitro_*`): - Read the `nitro://account` resource for brand fields (company name, brand colour, logo, fonts, physical address, voice document if present). - Call `nitro_get_status` for onboarding state and any obvious gaps. - Call `nitro_query({ entity: "templates", limit: 3 })` to see prior design language. Look at the actual sections, colours, typography, and tone. If the connected ESP is something else, look for the equivalent — most ESPs expose a brand or settings endpoint. If the ESP is unknown, fall back to project files: `BRAND.md`, `email-brand.md`, `PRODUCT.md`, or a top-level `README.md` for tone clues. Build a brand profile in your head with these fields, marking each as `known`, `inferable`, or `missing`: - Company name, from-name, from-email, mission/tagline - Primary brand colour (hex), secondary if any - Logo URL - Voice descriptors (e.g. founder-personal, editorial, cheeky, technical, premium-restrained) - Footer essentials: physical address, social handles, unsubscribe handler If three or more fields are `missing`, you can ask. Otherwise default to inferred values and note them in the brief. --- ## Step 2 — Up to three questions (only if needed) Hard cap: **three questions, in one message, as a numbered list**. If more fields are missing, fill with sensible defaults and note them in the brief — do not interrogate. Priority order — pick the top three that are missing and matter for *this specific email*: 1. **Email purpose** — what does this specific email need to do? (Drive a click? Tell a story? Confirm an action? Re-engage a lapsed user? Tease a launch?) Almost always worth asking on first email of a session. 2. **Tone register** — editorial, bold-mono, minimal-lux, founder-letter, punk/character, or lookbook? Ask only if voice is unclear from prior templates. 3. **Primary brand colour** — hex preferred. Ask only if missing AND no logo to extract from. 4. **Mission line** — one sentence on why the company exists (not what it sells). Ask only if footer-critical and absent. 5. **Socials + physical address** — handles + one mailing address for footer / CAN-SPAM. Ask only if footer would otherwise be incomplete. If the user has already answered these earlier in the session, do not re-ask. --- ## Step 3 — Pick an archetype, then write the brief Anti-slop wins. Commit to an archetype before drafting. The most common failure mode is defaulting to "minimal-lux" because it feels safe — it is the right answer maybe 30% of the time. For the rest, pick deliberately. ### Archetypes | Archetype | When | Hallmarks | Reference brands | |---|---|---|---| | **Editorial** | Newsletters, brand stories, long-form | Serif heads, full-bleed photo, generous leading, single column, voice-rich | Patagonia, Tracksmith, Lucy Folk | | **Bold mono** | Promo, launches, statements | One saturated colour drenches the surface, big punchy type, minimal copy | Absolut, Liquid Death, Fly By Jing | | **Minimal lux** | Premium, transactional, restraint as positioning | Tinted neutrals, narrow width 472–520px, one accent, lots of breath, never discount-led | Stripe, Aesop, Apple, MoMA | | **Founder letter** | Welcome, win-back, milestones, reply-driver | Plain-text feel, first-person, short paragraphs, signed off, no template chrome | Ugmonk, Superhuman, Tracksmith CEO | | **Punk / character** | Brand voice carriers, retention | Heavy personality, mascot or character, irreverent copy, custom imagery | Frank Body, Duolingo, Liquor Loot, Chubbies | | **Lookbook** | Product, fashion, food, paint, anything where the product *is* the design | Editorial photo > copy, gallery layout, full-bleed hero | Dior, Clare Paint, Starbucks seasonal | ### Shared visual laws Apply to every archetype. Implementation should match the aesthetic — bold needs committed; minimal needs precision. #### Colour - Pick a strategy *before* picking colours: - **Restrained** — tinted neutrals + one accent ≤10% of the surface. Default for transactional and minimal-lux only. - **Committed** — one saturated colour carries 30–60% of the surface. Default for brand-identity emails. - **Drenched** — the surface IS the colour. For heroes and statement emails. - Never pure `#000` or `#fff`. Tint every neutral toward the brand hue. - High chroma at extreme lightness looks garish; pull saturation back as you approach black or white. - **Category-reflex check.** If someone could guess the palette from the category alone — fintech → navy + gold, wellness → white + sage, AI → black + neon, ecommerce → millennial pink + cream — rework it. Training-data reflexes make emails forgettable. #### Typography - One typeface family per email. Add a second only with a clear functional reason. - Body 14–16px. Headline 22–34px. Hierarchy ratio ≥1.25 between steps. - Cap line length 50–65 characters. - No gradient text. No `background-clip: text`. Emphasis through weight or size, not effects. #### Layout - Single column. Width 472–600px. Wider feels desktopy and breaks on mobile. - Vary spacing for rhythm. Same padding everywhere reads as wireframe. - Cards are the lazy answer. Use only when truly the best affordance. Nested cards are always wrong. - Touch targets ≥44×44px. #### Whitespace (this is where most AI-drafted emails fail) The default LLM behaviour is to over-pad — every section gets generous top *and* bottom padding, plus standalone spacer rows. The result is a moonscape. Counteract: - **No orphan spacers.** Two `spacer` sections in a row, ever, is wrong. Collapse. - **Asymmetric padding.** Most sections: `padding_top: 0, padding_bottom: 32`. Let the next section's top padding (or its lack) own the rhythm. - **Hero hugs.** Hero image sits flush to header (≤8px gap), generous space *below* the hero, not both sides. - **End rule.** Final content section before footer: `padding_bottom: 32–48px`, never more. Footer has its own top padding. - **Never:** two consecutive empty paragraphs, double `
` between blocks, margin AND padding on the same side, an empty `text` section used as a spacer. This applies regardless of platform whitespace-trimming passes — belt and braces. #### Imagery - Real photography or commissioned illustration only. No stock, no AI slop, no flat geometric shapes as decoration. - Hero must serve a purpose: product, person, place, or moment. Decoration is not enough. - Each image ≤200KB; total payload ≤800KB. - Alt text on every image. Treat as fallback for the ~33% who block images. - Dark mode: transparent PNGs for logos and icons; off-white (not pure white) backgrounds. #### Copy - Inverted pyramid. Lead with the answer. - Short paragraphs. Every word earns its place. - No restated headings. No intro paragraphs that repeat the subject. - No em dashes (—) or en dashes (–) in body. Use commas, colons, semicolons, periods, parentheses. No `--`. - One CTA above the fold. A second CTA at the bottom is fine. More than two is dilution. - Subject ≤45 chars. Preheader ≤90 chars. Both must add information; never restate the subject. ### The brief (structured) Write the brief as JSON before composing sections. This is what feeds the sending tool. Treat it as the contract. ```json { "name": "Campaign or template name", "subject": "subject line ≤45 chars", "preheader": "preheader ≤90 chars adding new info", "archetype": "editorial | bold-mono | minimal-lux | founder-letter | punk-character | lookbook", "color_strategy": "restrained | committed | drenched", "primary_color": "#hex", "secondary_color": "#hex or null", "voice_descriptors": ["e.g. founder-personal", "wry", "concrete"], "structure": [ { "kind": "header", "logo": true, "padding": "compact" }, { "kind": "hero", "image_slot": "" }, { "kind": "headline", "content": "..." }, { "kind": "body", "content": "..." }, { "kind": "cta", "label": "...", "url": "..." }, { "kind": "secondary_body", "content": "..." }, { "kind": "footer" } ], "image_slots": [ { "slot_id": "hero", "purpose": "what it must convey", "candidate_url": "", "user_prompt": "" } ], "footer": { "mission_line": "exact verified copy from brand fields or brand site, or null — never invent", "socials": [{ "name": "instagram", "url": "..." }], "physical_address": "one line", "unsubscribe": "{{unsubscribe_url}}" }, "anti_slop_checks": ["no category-reflex palette", "real imagery", "distinctive voice"] } ``` --- ## Step 4 — Resolve image slots Each `image_slot` must end with a real candidate URL or an explicit prompt to the user. Sources, in priority order: 1. **Already-uploaded brand assets.** If Nitrosend is connected: `nitro_query({ entity: "media" })`. Use what's there before fetching anything new. 2. **Brand site.** Fetch `https:///` with WebFetch and look for: - `` - hero image on the homepage (look for `
img`, `
img`, `[data-hero] img`, banner-y filenames) - `/press`, `/about`, or `/blog` page imagery for portraits and lifestyle - Prefer images ≥1200px on the long edge. 3. **Brand social profiles.** Instagram or X profile images for portraits and lifestyle moments. 4. **Prompt the user — once.** Concrete description, options included: *"For the hero I'm picturing [X]. Got an image for that, or want me to leave a placeholder so you can drop one in via the media uploader?"* Never fabricate or AI-generate a stock-style image. A clearly-marked placeholder is better than visual slop. If you uploaded a new image and the brand uses Nitrosend: `nitro_ingest_image({ url: "...", purpose: "hero" })`. --- ## Step 5 — Translate the brief and hand off Map the brief's `structure` array to the sending tool's section types. For Nitrosend `nitro_compose_campaign`: | Brief kind | Nitrosend section | Notes | |---|---|---| | header | omit if logo lives in `theme.logo_url`; otherwise `image` | Logo height 32–48px | | hero | `image` | Full-width, no side padding, set `link_url` only if it's clickable | | headline | `text` with `

` or `

` markup | Don't add a separate spacer above; let the next section's top padding handle rhythm | | body | `text` | Short paragraphs | | cta | `button` | Single CTA, full-width on mobile | | secondary_body | `text` | Optional | | divider | `divider` | Once per email max | | footer | `footer` | Auto-rendered if account footer is configured; otherwise build explicitly | ### Whitespace overrides on the call Override the platform's default padding when composing. Do this even if the platform has a whitespace-trimming pass. ```json { "type": "image", "props": { "src": "...", "alt": "...", "padding_top": 0, "padding_bottom": 24 } } ``` Default rule per section: `padding_top: 0, padding_bottom: 32`. Override only with reason. ### Footer — the part most AI emails get wrong A great footer, in this order: 1. **Mission line.** One sentence. *Why* the company exists, not what it sells. ("Made for runners. Made in Boston." beats "Premium athletic apparel since 2014.") **Do not guess or invent this.** Pull verbatim from one of: the connected ESP's brand fields (Nitrosend: `company_description` on the brand, also visible in the Brand settings), or the brand's homepage / about page (hero subhead, footer tagline, "we believe…" copy). If neither yields an exact, verified line, **omit the mission line entirely** — a missing mission is better than a fabricated one. 2. **Social icons.** 3–5 max. Real handles, real URLs. 24–32px icons. 3. **Physical address.** Required for CAN-SPAM. Single line. 4. **Unsubscribe link.** Visible, not microscopic. The word "unsubscribe", not a buried "preferences" euphemism. Required for CAN-SPAM and Gmail/Yahoo bulk-sender rules. 5. **Optional:** tagline, contact email, "you're getting this because…" reason. Visual: smaller type (12–13px), tinted neutral text at 60–70% of body contrast, generous internal padding, no extra spacer above. ### The handoff Always run a dry-run first and always show the preview URL before the user approves a real send. Ask if they want a test email. ``` nitro_compose_campaign({ name: brief.name, subject: brief.subject, preheader: brief.preheader, sections: , theme: { brand_color: brief.primary_color, bg_color: ..., text_color: ..., font_body: ..., font_heading: ..., logo_url: ... }, audience: { audience_type: "lists", contact_list_ids: [...] }, dry_run: true }) ``` Then surface the preview URL from the response. Only proceed to a real send after the user confirms. ### Offer a test send After the dry-run preview, before any real send, ask: > *"Want me to send you a test email first? I can send to [from_email from account] or another address — let me know."* Default the recipient to the account's `from_email` or the saved test recipients, but accept any address the user names. If they say yes, send via the platform's test endpoint and surface the result. For Nitrosend: ``` nitro_send_test_message({ template_id: , email: "" }) ``` For other ESPs, use the equivalent (`POST /v1/my/templates/{id}/send_test` on the Nitrosend REST API; analogous endpoints elsewhere). After the test lands, ask if any final tweaks are needed before the real send. --- ## Pre-handoff checklist Run this mentally before composing. If three or more fail, redraft. - [ ] Subject ≤45 chars, adds information - [ ] Preheader ≤90 chars, doesn't restate subject - [ ] One archetype, applied consistently - [ ] Colour strategy committed (not "neutrals + accent" by reflex unless minimal-lux) - [ ] No category-reflex palette - [ ] At least one real image, sourced or explicitly prompted - [ ] Single CTA above the fold; ≤2 total - [ ] Footer has socials + physical address + unsubscribe (mission line only if verified — never invented) - [ ] No double spacers, no `

`, no margin+padding combos - [ ] No em dashes in body - [ ] Single column ≤600px; touch targets ≥44px - [ ] Voice is recognisable as the brand, not a template - [ ] Offered a test send to the user before any real send ## Pushback patterns When the user wants to iterate: - **"Make it bolder"** → escalate colour strategy (restrained → committed → drenched), increase type contrast, shrink line lengths, swap to bold-mono or punk-character archetype. - **"Make it quieter"** → de-escalate colour, increase whitespace selectively (not uniformly — that's the moonscape failure mode), strip secondary CTAs, swap to minimal-lux or editorial. - **"Add personality"** → swap to founder-letter or punk-character; rewrite copy first-person; add one unexpected element (handwritten asset, mascot, ridiculous subject line). - **"Too plain"** → almost always means the archetype is wrong. If you defaulted to minimal-lux, ask once whether they want bold-mono or lookbook instead. - **"Looks like AI made it"** → category-reflex palette, stock-feeling imagery, or no voice. Diagnose which one and fix only that. ## Examples ### Brief — SaaS welcome email (founder-letter) ```json { "name": "Welcome 1 — Founder Hello", "subject": "you're in", "preheader": "a quick note from the founder, plus what to expect this week", "archetype": "founder-letter", "color_strategy": "restrained", "primary_color": "#1f2933", "voice_descriptors": ["first-person", "concrete", "warm", "no marketing fluff"], "structure": [ { "kind": "header", "logo": true, "padding": "compact" }, { "kind": "headline", "content": "Hey, I'm [name]." }, { "kind": "body", "content": "Three short paragraphs. What we built, why we built it, what to do this week." }, { "kind": "cta", "label": "Reply with one thing you're trying to do", "url": "mailto:..." }, { "kind": "footer" } ], "image_slots": [], "footer": { "mission_line": "Building [thing] so [who] can [outcome].", "socials": [{ "name": "linkedin", "url": "..." }], "physical_address": "...", "unsubscribe": "{{unsubscribe_url}}" }, "anti_slop_checks": ["plain-text feel keeps it personal", "no stock imagery", "single CTA is a reply, not a click"] } ``` ### Brief — D2C product launch (bold-mono, drenched) ```json { "name": "Launch — Nitro Blue Drop", "subject": "blue.", "preheader": "the new colorway. limited run. tomorrow 9am.", "archetype": "bold-mono", "color_strategy": "drenched", "primary_color": "#1d4ed8", "voice_descriptors": ["punchy", "confident", "few words"], "structure": [ { "kind": "hero", "image_slot": "hero" }, { "kind": "headline", "content": "Blue." }, { "kind": "body", "content": "Limited to 200. 9am tomorrow." }, { "kind": "cta", "label": "Set a reminder", "url": "..." }, { "kind": "footer" } ], "image_slots": [ { "slot_id": "hero", "purpose": "Single product shot on solid background. Same blue as primary_color. No text overlay.", "candidate_url": "https://brand.com/og-image.jpg", "user_prompt": "Got the product photo of the blue colorway? Drop the URL or upload via the media uploader." } ], "footer": { "mission_line": "Made for runners. Made in [city].", "socials": [ { "name": "instagram", "url": "..." }, { "name": "tiktok", "url": "..." } ], "physical_address": "...", "unsubscribe": "{{unsubscribe_url}}" }, "anti_slop_checks": ["committed to one colour", "real product photo, not stock", "no double-padding"] } ``` ### Brief — Editorial newsletter (Patagonia-style) ```json { "name": "Newsletter — Running gear for winter's worst", "subject": "running gear for winter's worst", "preheader": "what we wear when it's brutal out there", "archetype": "editorial", "color_strategy": "committed", "primary_color": "#0a3d2e", "voice_descriptors": ["earnest", "specific", "outdoorsy", "sells the weather, not the product"], "structure": [ { "kind": "header", "logo": true, "padding": "compact" }, { "kind": "hero", "image_slot": "winter-trail" }, { "kind": "headline", "content": "When the weather wins, you don't." }, { "kind": "body", "content": "Short essay — 120 words on running in horizontal sleet. No product names yet." }, { "kind": "cta", "label": "See the kit", "url": "..." }, { "kind": "secondary_body", "content": "Three pieces, briefly. Photo above each, not in a grid card." }, { "kind": "footer" } ], "image_slots": [ { "slot_id": "winter-trail", "purpose": "Editorial landscape — runner small in frame, weather doing the talking. No product close-ups in the hero.", "candidate_url": null, "user_prompt": "Have a winter trail / weather shot? Or shall I leave a placeholder?" } ], "footer": { "mission_line": "We're in business to save our home planet.", "socials": [{ "name": "instagram", "url": "..." }], "physical_address": "...", "unsubscribe": "{{unsubscribe_url}}" }, "anti_slop_checks": ["no category-reflex green-and-brown palette", "hero sells the moment, not the product", "voice carries the email, not the design chrome"] } ```