Claude Opus 4.5 - The Master Architect

Claude Opus 4.5 powers your Softgen agent with the world's best model for coding. It's state-of-the-art on software engineering benchmarks and dramatically more efficient than previous Opus models—using up to 65% fewer tokens while achieving higher quality.

Why Choose Claude Opus 4.5?

Perfect for:

• Long-horizon autonomous coding tasks
• Complex multi-step reasoning and planning
• Code refactoring across multiple codebases
• Enterprise applications with sophisticated requirements
• Production code that requires reliability and precision

Real User Experiences:

"Claude Opus 4.5 handles long-horizon coding tasks more efficiently than any model we've tested. It achieves higher pass rates on held-out tests while using up to 65% fewer tokens." - Sean Ward, CEO Sweep

"Claude Opus 4.5 delivered an impressive refactor. It was very thorough, helping develop a robust plan, handling the details and fixing tests." - Paulo Arruda, Staff Engineer at Slack

"At medium effort level, Opus 4.5 matches Sonnet 4.5's best score on SWE-bench Verified, but uses 76% fewer output tokens." - Anthropic Engineering

What You Get

• State-of-the-Art Coding: Leads across 7 out of 8 programming languages on SWE-bench Multilingual
• Token Efficiency: Uses 48-76% fewer tokens than Sonnet 4.5 while matching or exceeding quality
• Advanced Planning: Excels at building precise plans and executing multi-step tasks
• Creative Problem Solving: Finds insightful, legitimate solutions to complex problems

Pricing Reality

Official Rates: $5 per 1M input tokens / $25 per 1M output tokens

What this means for you:

• Small projects: ~$2-5 per session
• Medium projects: ~$5-15 per session
• Large enterprise projects: ~$15-40 per session

Now at a price point where Opus can be your go-to model for most tasks, with dramatically better efficiency than previous Opus versions.

Technical Capabilities

• Effort Control: New parameter lets you balance speed/cost vs. capability
• Extended Thinking: 64K thinking budget for complex reasoning
• 200K Context Window: Handles large codebases and complex requirements
• Advanced Tool Use: Better at using computers, spreadsheets, and handling long-running tasks
• Fewer Iterations: Requires fewer steps to solve tasks with more precise execution

Performance Highlights

SWE-bench Verified Leadership: State-of-the-art on real-world software engineering tests

Token Efficiency:

• At medium effort: Matches Sonnet 4.5 quality with 76% fewer output tokens
• At high effort: Beats Sonnet 4.5 by 4.3 points with 48% fewer tokens

Real-World Impact:

• 50-75% reduction in tool calling errors and build/lint errors
• 15% improvement on Terminal Bench over Sonnet 4.5
• 20% accuracy improvement on Excel automation and financial modeling
• Handles 30-minute autonomous coding sessions with consistent performance

When to Use a Different Model

• Simple landing pages (try Gemini 3 Pro)
• Rapid iteration on simple concepts (try GPT 5.1)
• When you need the absolute fastest speed over quality (try Haiku 4.5)

The Bottom Line

Claude Opus 4.5 represents a breakthrough: Opus-level intelligence at a much more accessible price point. With dramatically improved efficiency, it can now be your daily driver for complex work.

Choose it when you need:

• Complex refactoring across multiple codebases with coordination
• Reliable execution with fewer errors and iterations
• Advanced reasoning for sophisticated business logic and planning
• Production-quality code that works right the first time

At $5/$25 per million tokens with 48-76% token savings, Opus 4.5 delivers frontier capabilities at prices that make sense for regular use.

Best for: Complex coding tasks, code refactoring, production applications, and any project where you need the best available reasoning and execution quality.

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Want to learn more? Read the official Claude Opus 4.5 announcement from Anthropic for technical benchmarks and capabilities.