---
id: "entity-claude-code"
type: "entity"
entityType: "product"
canonicalName: "Claude Code"
aliases: []
source_timestamps: ["§ The Coupling of Model Training and Harness Design"]
tags: ["product", "agent"]
related: ["concept-harness-model-coevolution", "entity-opus-4-6", "contrarian-harness-optimization"]
canonicalUrl: "https://www.anthropic.com/news/claude-code"
---
# Claude Code

## Profile

**Claude Code** is Anthropic's coding-agent product, built around the Claude model family. It is a canonical example of a sophisticated harness ([[concept-agent-harness]]) with repo context, file tools, bash access ([[concept-bash-general-tool]]), and IDE integration.

## Role in This Source

Cited as the prototypical example of [[concept-harness-model-coevolution|model–harness co-evolution]]: Claude models are post-trained with Claude Code's harness in the loop, making the model natively good at file edits, bash execution, and planning within that environment.

It is also the foil for the contrarian observation [[contrarian-harness-optimization]] — that [[entity-opus-4-6|Opus 4.6]] running inside Claude Code can actually underperform Opus 4.6 running in other, more optimized harnesses on benchmarks like [[entity-terminal-bench-2-0|Terminal Bench 2.0]].