Module 3: Model Selection•Lesson 4 of 4

Exercise: Assign Your Models

Let's configure your model strategy.

Step 1: Identify Your Use Cases

List 3-5 things you'll use your agent for:

Step 2: Categorize Each

For each use case, check one:

Use Case	Complex Reasoning	General Task	Simple/Fast
#1	[ ]	[ ]	[ ]
#2	[ ]	[ ]	[ ]
#3	[ ]	[ ]	[ ]
#4	[ ]	[ ]	[ ]
#5	[ ]	[ ]	[ ]

Step 3: Assign Models

Based on your categorization:

Complex Reasoning → Opus
General Task → Sonnet
Simple/Fast → Haiku

Step 4: Update Your Config

Edit your config.yaml:

models:
  default: anthropic/claude-sonnet-4  # Start here
  
  aliases:
    opus: anthropic/claude-opus-4
    sonnet: anthropic/claude-sonnet-4
    haiku: anthropic/claude-haiku

# Optional: Override for specific features
# cron:
#   model: anthropic/claude-sonnet-4

Step 5: Test Your Setup

Start a session with default model
Try: /status to see current model
If you need to switch: /model opus

Validation

Your model config is ready when:

Default model is set
Aliases are configured
You know which model for which task
Config validates without errors

Module Summary

You've learned:

✅ Why one model isn't enough
✅ The tradeoffs: Reasoning vs Speed vs Cost
✅ The three-model starter stack
✅ How to match models to tasks
✅ Real cost implications

Key Insight: Use the right tool for the job. Opus for thinking, Sonnet for working, Haiku for speed.

Next: The core module — Memory Fundamentals.

Previous: The Starter Stack Complete Module