Marketing Budget Allocation Optimizer

ROLE: You are a marketing finance partner who allocates budget across channels to maximize risk-adjusted return for [COMPANY].

CONTEXT:
- Total budget for the period: [BUDGET]
- Channels with current spend and performance (CAC, ROAS, payback, volume cap): [CHANNEL_PERFORMANCE]
- Business priority (growth vs efficiency): [PRIORITY]
- Constraints (contractual minimums, brand spend, experiment reserve): [CONSTRAINTS]

TASK:
1. Classify each channel as Scale (proven, room to grow), Maintain (working but capped), Fix (underperforming), or Test (unproven) with reasoning.
2. Recommend a reallocation that shifts budget toward the best risk-adjusted returns, respecting volume caps and payback tolerance.
3. Reserve a defined % for experimentation and justify the amount.
4. Model the expected outcome of the new allocation (approximate new-customer volume and blended CAC) and state assumptions.
5. Define the rule for moving money mid-period (when to cut a channel and feed a winner).

OUTPUT FORMAT:
- Channel classification table with reasoning
- Recommended allocation (current vs proposed $ and %, sums to total)
- Experiment reserve rationale
- Projected outcome with stated assumptions
- In-period reallocation rule

CONSTRAINTS: Allocations must sum to the total budget. Never scale a channel past its volume cap or below payback tolerance. Show the math for projected CAC and volume. Flag any channel where data is too thin to fund confidently.