Do I need to route requests based on cost and latency?

Usually, yes—if you have multiple models/services and care about efficiency or user experience.

Route by cost when:

• You want to keep spend under control
• Some requests are simple and can use cheaper models
• You have high volume and cost differences are meaningful

Route by latency when:

• Some requests need fast response times
• Users are sensitive to delays
• You can send urgent/simple requests to lower-latency backends

A common approach

Use a router that considers:

• Request complexity
• Required quality
• Budget constraints
• Latency SLOs
• Current system load

For example:

• Cheap/fast model for autocomplete, classification, extraction
• Higher-quality model for reasoning, long-form generation, or tricky cases

If you only have one backend

Then routing by cost/latency usually doesn’t matter much—unless you’re deciding between different deployments or regions.

Practical recommendation

Start simple:

1. Define 2–4 request categories
2. Map each category to a default model
3. Add fallback rules for:
   • timeout
   • overload
   • budget cap
   • quality escalation

If you want, I can help you design a routing policy based on your models, traffic, and budget.