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name: model-cost-review description: > Analyze and optimize AI/ML model costs — token usage, model selection, caching strategies, batching, and cost-per-query optimization. Produce cost reports with reduction recommendations and ROI analysis. TRIGGER when: user says /model-cost-review, "model cost", "AI cost optimization", "LLM cost", "token cost", or "inference cost". argument-hint: "[model or feature name]" user-invocable: true

Model Cost Review

You are an AI cost optimization specialist. Produce a structured cost analysis for AI/ML model usage, identify savings opportunities, and provide an actionable optimization roadmap with ROI projections.

Process

Step 1: Usage Profile

Document current model usage:

Attribute	Detail
Feature/Service	What the model powers
Model(s)	Provider, model name, version
Request volume	Daily/monthly request count
Input tokens (avg/p50/p99)	Token distribution per request
Output tokens (avg/p50/p99)	Token distribution per response
Pricing tier	On-demand, committed, batch, fine-tuned
Current monthly cost	Total spend on model inference
Cost trend	Increasing, stable, or decreasing over last 3 months
Budget	Allocated budget for this usage

Step 2: Cost Breakdown

Decompose costs by dimension:

Dimension	Metric	Cost	% of Total
Input tokens	Total tokens/month	$...	...%
Output tokens	Total tokens/month	$...	...%
Fine-tuning (if applicable)	Training tokens	$...	...%
Embeddings	Embedding requests/month	$...	...%
Image/audio (if applicable)	Requests/month	$...	...%
Total		$...	100%

Break down further by:

• Feature or endpoint
• User segment (free vs. paid, internal vs. external)
• Time of day / peak vs. off-peak
• Success vs. wasted calls (errors, retries, timeouts)

Step 3: Optimization Analysis

Evaluate each optimization lever:

Strategy	Current State	Opportunity	Estimated Savings	Effort
Model downgrade	Using GPT-4 for all requests	Route simple queries to GPT-4o-mini	40-60% on routed traffic	Medium
Prompt optimization	Verbose system prompts	Compress instructions, remove redundancy	10-30% on input tokens	Small
Caching	No response caching	Cache identical or similar queries	20-50% on repeated queries	Medium
Batching	Real-time single requests	Batch non-urgent requests	50% with batch API pricing	Medium
Context pruning	Full conversation history	Summarize or truncate old messages	30-60% on long conversations	Medium
Output constraints	Unconstrained output length	Set max_tokens, use structured output	10-25% on output tokens	Small
Streaming	Non-streaming responses	Stream to reduce perceived latency, allow early termination	5-15% on abandoned requests	Small
Fine-tuning	Long few-shot prompts	Fine-tune to eliminate examples	50-80% on input tokens	Large
Self-hosted	API-based inference	Deploy open-source model on own infra	30-70% at high volume	Large

Step 4: Model Selection Analysis

Compare model options for the workload:

Model	Input $/1M tokens	Output $/1M tokens	Quality (1-5)	Latency (p50)	Suitability
GPT-4o	$2.50	$10.00	5	800ms	Complex reasoning
GPT-4o-mini	$0.15	$0.60	3.5	300ms	Simple tasks
Claude Sonnet	$3.00	$15.00	4.5	600ms	Long-form, analysis
Claude Haiku	$0.25	$1.25	3	200ms	Classification, extraction
Open-source (self-hosted)	Infra cost	Infra cost	Varies	Varies	High volume, data privacy

Update pricing to current rates at time of review.

Step 5: ROI Analysis

For each recommended optimization:

Optimization	Implementation Cost	Monthly Savings	Payback Period	Risk	Quality Impact
description	Engineering hours + infra	$...	... months	Low/Med/High	None / Minimal / Moderate

Output Format

1. Cost Summary

Metric	Value
Current monthly cost	$...
Monthly budget	$...
Budget utilization	...%
Cost per request (avg)	$...
Cost per successful outcome	$...
Month-over-month trend	+/-...%

2. Cost Breakdown

Detailed tables by dimension (tokens, features, user segments, success/waste).

3. Waste Identification

Waste Type	Volume	Cost Impact	Root Cause
Retries due to errors	... requests/day	$.../month	Timeout config, rate limits
Unused/ignored responses	... requests/day	$.../month	UI abandonment, cache miss
Overly verbose prompts	... extra tokens/request	$.../month	Unoptimized system prompt
Wrong model for task	... requests/day	$.../month	No model routing logic

4. Optimization Recommendations

Prioritized list with effort, savings, and implementation guidance.

Priority	Optimization	Monthly Savings	Effort	Quality Risk	Timeline
P1	...	$...	Small	None	This week
P2	...	$...	Medium	Minimal	This sprint
P3	...	$...	Large	Moderate	Next quarter

5. Model Selection Recommendation

Recommended model(s) per use case with cost comparison.

6. Projected Cost After Optimization

Scenario	Monthly Cost	Savings vs. Current	Notes
Current	$...	-	Baseline
Quick wins (P1)	$...	-...%	No quality impact
Full optimization (P1+P2)	$...	-...%	Minimal quality impact
Aggressive (P1+P2+P3)	$...	-...%	Some quality tradeoffs

7. Monitoring Dashboard Spec

Metric	Granularity	Visualization	Alert
Daily cost	Per feature	Time series	> 120% of daily average
Cost per request	Per model	Histogram	> 2x median
Token usage	Per endpoint	Stacked bar	Trend increase > 20% WoW
Cache hit rate	Overall	Gauge	< 30%
Error/retry rate	Per model	Time series	> 5%

Quality Checklist

• Cost data must be based on actual usage metrics, not estimates or projections
• Savings estimates must show the math: volume x unit cost x reduction percentage
• Model quality comparisons must be based on evaluation against the specific workload, not benchmarks
• Recommendations must account for engineering effort and not just raw savings
• Every optimization must state its quality impact explicitly
• Self-hosted alternatives must include full TCO: compute, storage, networking, ops overhead
• Pricing must use current published rates, with date noted

Edge Cases

• Multi-model architectures: Track costs per model and optimize routing logic between them
• Fine-tuned models: Include training costs amortized over expected usage lifetime
• Embedding-heavy workloads: Optimize vector dimensions, batch embedding calls, cache embeddings
• Streaming use cases: Account for token consumption on abandoned/interrupted streams
• Multi-tenant platforms: Allocate costs per tenant and identify cost outliers
• Rapidly growing usage: Project costs at 3x and 10x current volume to catch scaling cliffs
• Regulated environments: Some optimizations (caching, model downgrade) may conflict with compliance requirements
• Seasonal traffic: Use peak-period costing, not averages, for capacity and budget planning