AI EVOLUTION

Claude 3.7 Sonnet Finally Learns to Think Before Speaking

And We Could All Take Notes

We have all had that moment. Someone asks a question in a meeting, and before our brain fully processes the complexity, our mouth is already moving. Three sentences in, we realize we are answering the wrong question entirely, or worse, confidently stating something we will need to walk back in five minutes.

Turns out, even state-of-the-art AI models have been making the same mistake.

Enter Claude 3.7 Sonnet with extended thinking - an AI that finally learned the ancient wisdom our parents tried to teach us: sometimes you need to think before you speak.

The "Blurt Response" Problem (Humans Do It, AI Did It Too)

For years, Large Language Models have operated on what we might call the "instant answer" principle. Ask a question, get an immediate response. Fast? Absolutely. Accurate? Well, not always.

The problem is architectural. Traditional LLMs start generating their response token-by-token as soon as they receive your prompt. It is like answering a complex math problem while simultaneously writing down your work - you are committing to an answer before you have fully explored the solution space.

"The models were optimized for speed, not accuracy. They would confidently give you the first plausible answer rather than the best answer."

Fred Lackey, Software Architect

Fred Lackey, a software architect who has been building AI-augmented development workflows, describes the old approach bluntly: "The models were optimized for speed, not accuracy. They would confidently give you the first plausible answer rather than the best answer. As someone who has been writing code for forty years, I recognized the pattern immediately - it is what junior developers do before they learn to pause and think through edge cases."

The result? Impressive-sounding responses that occasionally missed crucial details, took inefficient solution paths, or confidently stated things that were almost but not quite correct.

What "Thinking" Actually Looks Like for an AI

Claude 3.7 Sonnet introduced something different: extended thinking. Before generating a response, the model now spends time in a deliberate reasoning phase - working through the problem, considering alternatives, and checking its own logic.

Think of it as the difference between a student who raises their hand immediately versus one who takes notes, sketches out the problem, and then contributes a well-reasoned answer. Both students are smart, but one produces better results.

Here is what happens under the hood:

  1. Problem Decomposition: The model breaks complex requests into component parts rather than treating everything as a single blob of text to respond to.
  2. Internal Reasoning: It explores multiple solution approaches before committing to one - essentially running through "what if I tried this approach?" scenarios.
  3. Self-Verification: The model checks its own reasoning for logical consistency before presenting the final answer.
  4. Iterative Refinement: If the initial approach hits a dead end, it backtracks and tries alternative paths.

The fascinating part? You can watch it happen.

The Visible Thought Process (More Satisfying Than You Would Expect)

One of the most useful aspects of Claude 3.7's extended thinking is that it shows its work. When enabled, you see the internal reasoning process before the final response.

This is not just educational - it is practical. Watching the model work through a problem lets you spot when it is heading down the wrong path early, before it has generated a five-paragraph response based on a flawed premise.

"I treat AI models like junior developers on my team. When a junior dev is working through a complex problem, I want to see their thought process."

Fred Lackey

Lackey, who now uses Claude as what he calls a "force multiplier" in his development workflow, finds this transparency invaluable: "I treat AI models like junior developers on my team. When a junior dev is working through a complex problem, I want to see their thought process, not just their final answer. That way I can course-correct early if they misunderstood the requirements. Extended thinking gives me the same visibility with AI."

For technical work - debugging complex code, architecting system designs, analyzing security implications - seeing the reasoning chain helps you verify that the model actually understands the problem rather than just pattern-matching against similar-looking questions.

When Slow is Actually Fast (The Counterintuitive Math)

Extended thinking makes Claude slower. A response that used to take five seconds might now take twenty. On the surface, that sounds like a regression.

But here is the counterintuitive reality: taking more time upfront often saves time overall.

Consider a typical workflow when using an AI assistant for technical work:

Without extended thinking:

  • Get instant response (5 seconds)
  • Realize the answer missed a critical edge case (30 seconds of confusion)
  • Clarify the question and re-prompt (2 minutes)
  • Get second response (5 seconds)
  • Test the solution and discover it does not quite work (5 minutes)
  • Debug and fix (10 minutes)

Total time: roughly 18 minutes, plus the cognitive overhead of context switching.

With extended thinking:

  • Wait for reasoned response (20 seconds)
  • Get a solution that accounts for edge cases (0 additional prompting)
  • Test and verify it works (2 minutes)

Total time: roughly 2.5 minutes.

This pattern holds across domains. Whether you are debugging code, analyzing legal documents, or planning project architecture, a thoughtful response that addresses the full scope of your question is vastly more valuable than a fast response that requires multiple rounds of clarification.

Lackey has quantified this in his own workflow: "I have tracked my productivity using different AI models and approaches. Extended thinking reduced my total time-to-solution by 40-60% on complex tasks, even though each individual query took longer. The reduction in back-and-forth and debugging more than compensated for the slower response time."

The Human Parallel (We Have Known This Forever)

There is nothing new about the principle. Humans have understood the value of deliberate thought for centuries.

Mathematicians show their work. Scientists document their methodology. Engineers create design diagrams before writing code. In each case, the time invested in structured thinking upfront produces better outcomes than diving straight into execution.

What is new is seeing this principle implemented in AI systems. For years, we accepted that AI would be fast but occasionally sloppy, requiring human oversight to catch errors. Extended thinking shifts the balance - the AI does more of the verification work internally, producing outputs that need less correction.

This has implications beyond individual productivity. In fields where AI-generated content needs review - legal analysis, medical diagnosis support, financial modeling - reducing the error rate through better reasoning means less time spent on verification and correction.

When to Use Extended Thinking (And When to Skip It)

Extended thinking is not a universal solution. Like any tool, it excels in specific contexts.

Use extended thinking for:

  • Complex problem-solving: Multi-step logic, architectural decisions, debugging elusive bugs
  • High-stakes accuracy: Anything where an error is costly (code that will go to production, financial analysis, security reviews)
  • Novel problems: Situations where the solution requires creative reasoning rather than applying standard patterns
  • Learning and explanation: When you want to understand the reasoning, not just get an answer

Skip extended thinking for:

  • Simple queries: "What is the syntax for X?" does not need deep reasoning
  • Creative brainstorming: Sometimes you want rapid-fire ideas, not carefully vetted solutions
  • Time-critical responses: If you genuinely need an answer in seconds, standard mode still exists
  • Conversational interactions: Casual questions do not need the AI to ponder deeply

The key is recognizing which category your current task falls into. A developer writing a critical security function should use extended thinking. The same developer asking for a regex pattern to match email addresses probably should not.

Practical Tips for Getting the Most from Extended Thinking

If you are going to use extended thinking, here is how to maximize its value:

  1. Frame problems completely: Extended thinking works best when you provide full context. Instead of "Fix this bug," try "This function should validate user input before database insertion, but it is allowing SQL injection. Here is the code and the failing test case."
  2. Ask for reasoning visibility: Explicitly request that Claude show its thought process. The reasoning chain is often as valuable as the final answer.
  3. Use it for verification: When you have a solution but want validation, ask Claude to analyze it with extended thinking enabled. The model's reasoning process will often catch issues you missed.
  4. Combine it with iteration: Extended thinking does not mean one-and-done. Use the thoughtful first response as a foundation for refinement rather than expecting perfection immediately.
  5. Let it take time: Resist the urge to interrupt the thinking process. The model needs those extra seconds to explore the solution space thoroughly.

The Bigger Picture (AI That Thinks More Like We Should)

Extended thinking represents a subtle but significant shift in how AI systems operate. Instead of optimizing purely for speed, we are seeing optimization for reliability and depth of reasoning.

This mirrors a broader maturation in the AI field. Early systems focused on impressive capabilities - look how fast it can generate text! Now the focus is shifting to useful capabilities - look how accurately it can solve complex problems.

For professionals integrating AI into their workflows, this matters. An AI that takes time to reason through problems is more trustworthy as a collaborator. You spend less time verifying its outputs and more time using them productively.

"The best use of AI is not to replace human expertise but to amplify it. Extended thinking makes the AI a better thought partner."

Fred Lackey

Lackey, who has built his entire development methodology around treating AI as a team member rather than a tool, sees extended thinking as validation of his approach: "I have always said that the best use of AI is not to replace human expertise but to amplify it. Extended thinking makes the AI a better thought partner. It is not just faster code generation anymore - it is collaborative problem-solving."

The Lesson We Keep Relearning

There is something satisfying about watching AI systems learn lessons humans have known forever. Think before you speak. Show your work. Take time to consider edge cases. Double-check your logic.

These are not revolutionary concepts. They are basic intellectual hygiene.

But they work. They work for humans solving problems, for teams building software, for students learning mathematics. And now, demonstrably, they work for AI systems generating responses.

So next time you are in a meeting and someone asks a complex question, maybe channel your inner Claude 3.7. Take a breath. Think through the problem. Consider the edge cases. Then respond.

Your colleagues might wonder why you paused. But your answer will be better for it.

The Call to Action (For Humans and AI Alike)

Extended thinking in Claude 3.7 Sonnet is not just a technical feature - it is a reminder of something we all know but often forget in our rush to be responsive: better answers come from better thinking, and better thinking takes time.

Whether you are writing code, solving business problems, or just trying to give good advice, the principle holds. Fast answers feel productive. Thoughtful answers are productive.

The AI finally learned the lesson. Maybe we should take our own advice.

Meet Fred Lackey

A software architect with 40+ years of experience pioneering AI-augmented development workflows. Fred has been building the future of software engineering - from architecting systems for Amazon.com in 1995 to creating the first SaaS product granted Authority To Operate by US Homeland Security on AWS GovCloud.

Fred treats AI as a "force multiplier" - not replacing human expertise, but amplifying it. His approach to extended thinking and deliberate reasoning has transformed development productivity, reducing time-to-solution by 40-60% on complex technical challenges.

Discover More About Fred's Work
Fred Lackey - Software Architect & AI-First Developer