Newsletter Blurb Copywriting

Prerequisites

• Partner newsletter audit completed (know their tone, audience, format)
• Clear value proposition for the partner's audience
• Landing page URL with UTM parameters ready
• Anthropic API key for Claude-powered copywriting

Steps

1. Gather context for the blurb. Before writing, collect:

   • Partner newsletter name and typical tone (formal/casual/technical)
   • Their audience persona (title, industry, pain points)
   • 2-3 example blurbs or ads from their previous newsletters (if available)
   • Your value proposition tailored to their audience
   • The landing page URL you want to drive traffic to
   • Any format constraints from the partner (word count, image allowed, CTA style)

2. Generate the blurb using Claude. Call the Anthropic API with a structured prompt:

   POST https://api.anthropic.com/v1/messages
   Authorization: Bearer {ANTHROPIC_API_KEY}
   Content-Type: application/json
   
   {
     "model": "claude-sonnet-4-20250514",
     "max_tokens": 1024,
     "messages": [{
       "role": "user",
       "content": "Write a co-marketing newsletter blurb (60-100 words) for placement in {partner_newsletter_name}.\n\nPartner audience: {audience_description}\nPartner tone: {tone}\nOur product: {product_description}\nValue prop for their audience: {value_prop}\nCTA URL: {landing_page_url}\n\nRules:\n- Match the partner's voice and tone\n- Lead with the reader's pain point, not our product\n- One clear CTA (not multiple)\n- No superlatives or hype words\n- Include a specific, concrete benefit\n- Keep under 100 words\n\nGenerate 3 variants: one curiosity-driven, one data-driven, one story-driven."
     }]
   }
   

3. Add UTM tracking to the CTA link. Every blurb link must include UTM parameters for attribution:

   {base_url}?utm_source={partner_slug}&utm_medium=newsletter&utm_campaign=co-marketing-shoutouts&utm_content={variant_id}
   

   Example: https://yourproduct.com/demo?utm_source=acme-weekly&utm_medium=newsletter&utm_campaign=co-marketing-shoutouts&utm_content=curiosity-v1

4. Validate the blurb. Before sending to the partner, check:

   • Word count within partner's constraints
   • CTA link works and UTM parameters fire in PostHog
   • No jargon the partner's audience wouldn't understand
   • The blurb reads as native content, not an ad
   • Spelling and grammar are correct

5. Send to partner for approval. Email the blurb variants to your partner contact. Include:

   • The blurb text (plain text, not HTML)
   • Any image/logo assets if the format allows
   • Suggested placement (top, middle, or end of newsletter)
   • The tracked CTA link
   • A note that they can edit for tone — the CTA link is the only non-negotiable

6. Archive the final version. Store the approved blurb in your CRM (Attio) linked to the partner record. Include: blurb text, variant used, partner newsletter issue date, and CTA URL. This creates a library of proven blurbs for reuse and optimization.

Error Handling

• If Claude generates off-brand copy, add 2-3 example paragraphs from the partner's newsletter to the prompt as few-shot examples
• If the partner rejects all variants, ask for a past sponsor blurb they liked and use it as a template
• If UTM parameters break the URL, URL-encode all parameter values

Alternative Tools

• OpenAI GPT-4: Alternative LLM for copywriting
• Jasper: Marketing-focused AI copywriter
• Copy.ai: Specialized in short-form marketing copy
• Manual writing: For high-stakes partnerships, human-written blurbs may outperform