Claude 3.7 Sonnet and Claude Code: An Early Coding Test

In February 2025 I review Claude 3.7 Sonnet and the Claude Code research preview, then test coding and mathematical tasks. I build up a Snake game with AI-controlled players; the video is an early hands-on look rather than a controlled comparison.

Anthropic presents Claude 3.7 Sonnet as a hybrid reasoning model that can give standard responses or use extended thinking. Claude Code is a separate command-line tool for agentic coding. Product features and access described here reflect the launch period.

I describe the visible thinking display and the ability for API users to set a thinking budget. The display should not automatically be assumed to expose every internal step, and token budgets, output limits and context windows are distinct settings.

Anthropic’s SWE-bench Verified chart shows 62.3% for Claude 3.7 Sonnet and 70.3% with custom scaffolding, compared with around 49% for the listed prior configurations. These are company-reported results under particular setups; the scaffold makes the comparison more than a raw model-only test.

A separate TAU-bench chart shows the new model ahead of the displayed alternatives on retail and airline tool-use tasks. I also discuss math, science and visual reasoning benchmarks, but those selected evaluations do not guarantee performance on all workflows.

I decide to update my older testing rubric because newer reasoning models do well on it. I note that my earlier Grok 3 test was not as demanding as it could have been, so the informal examples here should not be read as a fully controlled model comparison.

Claude Code quickly produces a basic Snake game in my demonstration. I then ask it to add AI control; after applying the generated changes I can toggle the agent and change speed, and the snake uses an A-star pathfinding approach to reach food.

The AI-controlled snake eventually makes a mistake and loses. I ask for a second automated snake, then add multiple food items and a temporary moving block that can defeat the other snake. The displayed game runs, though a short demonstration does not validate every rule or edge case.

For a hard integral, Grok 3 and Claude give different answers. I compare Claude’s result with o3-mini and tentatively prefer the agreement, but agreement between models is not itself a proof of a mathematical result.

I try the Basel problem using extended thinking. Claude gives the familiar result that the sum of reciprocal squares is π²/6, and I ask for a step-by-step explanation. Getting a famous result does not by itself prove that the derivation is sound.

Finally I ask about a recent Apple announcement and find that the tested interface does not answer with current information. I regard the apparent lack of live web access in this 2025 test as a drawback; the video does not establish the current capabilities of later versions.

My early impression is that the model performs well in the coding examples while having limitations. The experiments are a small set of launch-period demonstrations, so broader claims about reliability need additional testing.