Introduction to Claude Opus

Claude Opus is Anthropic's most capable AI model, designed to deliver state-of-the-art performance on highly complex tasks. The latest release, Claude Opus 4.8 (May 28, 2026), pushes reasoning, coding, and long-horizon autonomy further than any previous Claude model.

Why "Opus"?

The name "Opus" signifies a masterpiece or a work of significant scale. It sits at the top of the Claude model family:

Haiku: Fastest, most cost-effective.
Sonnet: Balanced performance and speed.
Opus: Maximum intelligence and capability.

Key Capabilities

1. State-of-the-Art Coding & Reasoning

Opus 4.8 scores 88.6% on SWE-bench Verified, 69.2% on the harder SWE-bench Pro, and 74.6% on Terminal-Bench 2.1 — outperforming GPT-5.5 and Gemini 3.1 Pro on several coding and reasoning benchmarks.

2. 1 Million Token Context

With a 1M token context window (and up to 128k output tokens), Opus can:

Analyze entire books, repositories, or long legal documents in a single prompt.
Hold context across very long agentic sessions.
Use adaptive thinking to spend more effort on harder problems.

3. More Honest, More Autonomous

Anthropic describes Opus 4.8 as having "sharper judgement, more honesty about its progress, and the ability to work independently for longer." It is roughly 4× less likely than Opus 4.7 to let flaws in its own code pass unflagged.

Best Use Cases

Research & Analysis Synthesizing trends from multiple complex reports.

Creative Writing Generating nuanced, high-quality prose with distinct tone.

Coding Solving difficult engineering problems and refactoring large codebases.

Agentic Workflows Planning and executing multi-step tasks autonomously over long horizons.

Getting Started

To use Claude Opus, you can:

Subscribe to Claude Pro on claude.ai.
Access the Anthropic API, Amazon Bedrock, Google Vertex AI, or GitHub Copilot (for developers).

"Opus lets us automate tasks that previously required human domain experts." — Early Beta Tester