Create a content campaign brief

**Role:** You are a Content Strategist designing a content campaign brief for {campaign_name}.

**Context:**
Content campaigns fail when they're built around content formats rather than business objectives and audience needs. A great campaign brief provides creative and operational clarity: what story are we telling, who are we telling it to, and what do we want them to think, feel, or do after encountering it?

**Task:**
Write a comprehensive content campaign brief that a content team can execute without needing to ask follow-up questions. Apply the big idea framework: find the one insight that connects what the brand needs to say with what the audience needs to hear.

**Input Available:**
- {campaign_name}: Campaign name or code
- {campaign_objective}: Business goal (brand awareness, lead generation, retention, product launch)
- {target_audience}: Primary audience including their situation, needs, and channel behavior
- {campaign_period}: Start and end dates
- {available_channels}: Distribution channels in scope
- {budget}: Available budget range
- {product_or_message}: What product, service, or message is the campaign about
- {brand_differentiator}: What makes the brand or message uniquely credible

**Output Format:**
1. Campaign summary: Objective, audience, period, budget in one paragraph
2. The big idea: The unifying creative concept across all content (1 sentence)
3. Key message architecture: Primary message | Secondary messages (3 max) | Proof points
4. Audience insight: The specific tension or desire that makes this campaign relevant to them now
5. Content pillars: 3–4 theme clusters with content ideas per pillar
6. Channel strategy: Channel | Content format | Frequency | Audience role | Expected outcome
7. Publishing calendar: Month-by-month content schedule with key milestones
8. Success metrics: Campaign KPIs with targets and measurement method
9. Do's and Don'ts: Brand and messaging guardrails for this campaign

**Guardrails & Quality Control:**
- The big idea must be differentiating — if the competitor could run the same campaign, it's not a strong idea
- Primary message must be singular — campaigns with multiple primary messages dilute impact
- Every channel must have a specific audience role: where they encounter the campaign in their journey
- Do not list tactics without tying each to a business objective and a success metric