Claude Code 2.1.220 Defaultly Switches to Opus 5, Nested Subagent Depth Expanded to 3 Layers
On July 24, 2026, Anthropic released the 2.1.220 series updates for Claude Code: version 2.1.219 switched the default model to Claude Opus 5 (1M context window), and expanded the default nested subagent depth from 1 to 3; version 2.1.218 changed `/code-review` to run as a background subagent. An early August evaluation showed that the gap between Opus 5 and GPT-5.6-Sol on Terminal-Bench 2.1 was less than 0.5 percentage points, and the competition for AI programming agents has shifted to focusing on both models and orchestration layers. This article sorts out the version changes based on the official CHANGELOG, and provides configuration instructions for subagent depth limits, concurrency upper limits and other parameters.
Read MoreAnthropic Releases Opus 5: New Default for Programming Agents, Half the Price of Fable 5 with Comparable Capabilities
On July 24, 2026, Anthropic released Claude Opus 5, making it the default model for Claude Code. Its pricing is the same as that of Opus 4.8, at $5/$25 per million tokens. The official stated that its capabilities are close to those of Fable 5, but the cost is only about half. The model enables adaptive thinking by default, and the effort parameter can be adjusted across five levels. It topped evaluations including Frontier-Bench v0.1 and GDPval-AA, and achieved 96.0% on SWE-bench Verified. On the same day, GitHub Copilot integrated Opus 5, covering multiple terminals such as VS Code and CLI. This article sorts out the evaluation data, key points of API migration, and suggestions for selecting between Opus 5 and Fable 5.
Read MoreClaude Opus 5 Released: 1M-Context Window Becomes Default Flagship Model of Claude Code
On July 24, 2026, Anthropic released Claude Opus 5, which features native 1 million-token context window, default thinking mode, and the same pricing as Opus 4.8. For Claude Code v2.1.219 and above, accounts such as Max/API will parse "Default" as Opus 5, while the default setting for Pro tier remains Sonnet 5. This article sorts out the specifications of Opus 5, Fast Mode and Effort levels, as well as the toolchain updates of Claude Code in July including Subagent background running, nested delegation, /code-review background review and /doctor self-check, and provides step-by-step guides for version checking and model switching.
Read MoreAnthropic Launches Claude Opus 5: Near Fable 5 Capabilities, Opus-Level Pricing
On July 24, 2026, Anthropic launched Claude Opus 5, keeping its pricing at $5/$25 per million tokens. The company stated that its coding and knowledge work intelligence is close to that of GPT-4o (Fable 5). It scores 96.0% on SWE-bench Verified and 79.2% on SWE-bench Pro, supports 1 million-token context window and effort adjustment, and has been launched on Claude API, Claude Code and AWS Bedrock. Developers are heatedly discussing the cost-performance ratio of Agent coding.
Read MoreCopilot Connects to Grok 4.5 and Claude Opus 5 in July, IDE Becomes a Battlefield for Agent Model Selection
On July 24 and 28, 2026, GitHub's official Changelog consecutively announced that Claude Opus 5 and Grok 4.5 have been integrated into GitHub Copilot, and users can switch between them via the model selector in VS Code, Copilot CLI, JetBrains and other entry points. Opus 5 is designed for complex long-chain Agent tasks, while Grok 4.5 boasts a maximum context window of 500,000 tokens and parallel tool calling. For Business/Enterprise plans, the feature requires administrators to enable the relevant policy, and Grok 4.5 is disabled by default. This article sorts out the access scope, plan differences, billing methods and selection references based on the official announcements.
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