Claude Opus should NOT be your default model
I keep seeing AI engineers and vibe coders saying:
"Just use Opus for everything"
I highly disagree
Opus is amazing when you need:
Deep reasoning
Complex debugging
Architecture decisions
High-stakes problems
Research into things you don't fully understand
That's exactly what it's built for
But once I understand the system...
Once I know the trade-offs...
Once I know what needs to be built...
I switch to Sonnet
Why?
Because at that point I'm not paying for intelligence
I'm paying for execution
One thing many vibe coders overlook is token consumption
It's not just about how many prompts you send
Different models generate different amounts of output and reasoning
A simple example:
Sonnet usually gets to the point faster
Sonnet is more concise
Sonnet lets you iterate quickly
Meanwhile:
Opus explores more possibilities
Opus adds more context
Opus generates longer responses
Which means the exact same workflow can consume significantly more tokens
Think of it this way:
Opus = A senior engineer doing a deep design review
Sonnet = A senior engineer helping you ship features all day
Both are valuable
But you don't schedule a full architecture review every time you need to change a button color
My rule:
Opus for unknown problems
Sonnet for known problems
Opus when complexity appears again
Using Opus for every prompt is like running a production Kubernetes cluster to host a static HTML page
The smartest model isn't always the best model
The best model is the one that gives you the right balance of:
Quality
Speed
Cost
Token efficiency
Most people optimize for model IQ
The best engineers optimize for throughput
Interviewer: "How do you code with AI?"
Me:
• Opus for coding
• Sonnet for research
Interviewer:
"Yeah, same. I haven't written code since AI went mainstream."
5 minutes later:
"Can you reverse a string in JavaScript and explain it line by line"
Interviewer: "How do you code with AI?"
Me:
• Opus for coding
• Sonnet for research
Interviewer:
"Yeah, same. I haven't written code since AI went mainstream."
5 minutes later:
"Can you reverse a string in JavaScript and explain it line by line"
@yamikoai its simple
function reverseString(str) {
let reversed = "";
for (let i = str.length - 1; i >= 0; i--) {
reversed += str[i];
}
return reversed;
}
console.log(reverseString("hello"));