Claude Opus 4.5: Best AI Model for Coding and Agents

Introduction

Anthropic has announced the release of Claude Opus 4.5, positioning it as the best AI model in the world for coding, agents, and computer use. This latest iteration sets new benchmarks for software engineering performance while dramatically improving efficiency and accessibility through reduced pricing and new developer controls.

The model represents a significant step forward in what AI systems can accomplish, particularly for complex, multi-step tasks that require sustained reasoning and autonomous execution. With state-of-the-art performance on real-world coding benchmarks and substantial improvements in efficiency, Opus 4.5 makes frontier AI capabilities more accessible to developers, teams, and enterprises.

Alongside the model release, Anthropic is introducing updates to the Claude Developer Platform, Claude Code, and consumer apps, including new tools for longer-running agents and expanded integrations with Excel, Chrome, and desktop applications. These updates demonstrate how advanced AI capabilities are becoming more practical and integrated into everyday workflows.

Key Capabilities and Performance

State-of-the-Art Coding Performance

Claude Opus 4.5 establishes new standards for AI-assisted software engineering:

SWE-bench Verified leadership: Achieves the highest scores on tests of real-world software engineering tasks
Efficient problem-solving: Solves complex coding challenges with fewer tokens and less backtracking
Multi-system debugging: Successfully figures out fixes for complex, multi-system bugs
Production-ready code: Delivers high-quality code that meets professional standards
Autonomous execution: Handles long-horizon coding tasks with sustained reasoning

The model's performance on SWE-bench Verified demonstrates its ability to work with real-world codebases, understand complex requirements, and implement solutions that pass actual test suites. This represents a significant advancement in practical AI coding capabilities.

Superior Agent Capabilities

Opus 4.5 excels at autonomous agentic workflows:

Long-horizon tasks: Handles complex, multi-step workflows with fewer dead-ends
Sustained reasoning: Maintains focus and coherence through extended autonomous sessions
Multi-agent coordination: Effectively manages teams of subagents for complex projects
Tool use efficiency: Uses fewer tool calls and tokens to achieve better results
Planning and execution: Builds more precise plans and executes them more thoroughly

Early testing shows that Opus 4.5 requires fewer steps to solve tasks and uses fewer tokens, indicating more precise reasoning and better instruction following. This efficiency makes it particularly valuable for production agent systems where cost and reliability matter.

Enhanced Computer Use

The model demonstrates significant improvements in computer interaction:

Spreadsheet expertise: Better performance on Excel automation and financial modeling
Browser navigation: Enhanced capabilities in Claude for Chrome across multiple tabs
Desktop integration: Improved functionality in the Claude desktop app
Multi-application workflows: Better coordination across different software tools
Long-running tasks: Handles extended computer use sessions without degradation

These improvements make Opus 4.5 particularly effective for office automation, data analysis, and complex workflows that span multiple applications and require sustained attention.

Efficiency and the Effort Parameter

Dramatic Token Efficiency Improvements

Claude Opus 4.5 uses dramatically fewer tokens than its predecessors to reach similar or better outcomes:

76% fewer tokens: At medium effort, matches Sonnet 4.5's best SWE-bench score using 76% fewer output tokens
48% fewer tokens: At highest effort, exceeds Sonnet 4.5 performance by 4.3 percentage points while using 48% fewer tokens
65% token reduction: Some workflows see up to 65% fewer tokens while achieving higher pass rates
Faster problem-solving: Less backtracking and redundant exploration means faster solutions

This efficiency improvement is crucial for production deployments where token costs directly impact operational expenses. The ability to achieve better results with fewer tokens represents a significant value proposition for enterprises.

New Effort Parameter

Anthropic introduces the effort parameter on the Claude API, giving developers control over efficiency vs capability tradeoffs:

Effort Levels:

Medium effort: Matches Sonnet 4.5's best score on SWE-bench Verified while using 76% fewer output tokens
High effort: Exceeds Sonnet 4.5 performance by 4.3 percentage points while using 48% fewer tokens
Flexible control: Developers can choose effort levels to minimize time and spend or maximize capability based on task requirements

Benefits:

Cost control: Developers can optimize for efficiency when appropriate
Quality optimization: Can maximize capability when needed
Dynamic adjustment: Different effort levels for different parts of workflows
Better resource allocation: Match computational resources to task complexity

The effort parameter represents a new level of control for developers, allowing them to optimize their AI usage based on specific needs and constraints. This is particularly valuable for applications that process many requests where small efficiency gains compound significantly.

Pricing and Accessibility

Reduced Pricing Structure

Claude Opus 4.5 introduces significantly reduced pricing:

Input tokens: $5 per million tokens (down from previous Opus pricing)
Output tokens: $25 per million tokens
API model name: claude-opus-4-5-20251101
Cloud availability: Available on all three major cloud platforms (AWS Bedrock, Google Cloud Vertex AI, and Microsoft Azure)

This pricing makes Opus-level capabilities accessible to a much broader range of users, teams, and enterprises. The combination of better performance and lower costs creates a compelling value proposition for organizations considering frontier AI models.

Expanded Availability

Opus 4.5 is available across multiple platforms:

Claude apps: Web, desktop, and mobile applications
Claude API: Direct API access for developers
Cloud platforms: AWS Bedrock, Google Cloud Vertex AI, Microsoft Azure
Claude Code: Integrated coding assistant
Enterprise solutions: Team and Enterprise plans

The broad availability ensures that developers and organizations can access Opus 4.5 through their preferred platform and integration method.

Safety and Alignment Improvements

Most Robustly Aligned Model

Claude Opus 4.5 represents Anthropic's most robustly aligned model to date:

Reduced concerning behavior: Significant improvements in alignment across a wide range of misaligned behaviors
Better judgment: Improved ability to reason about tradeoffs and avoid harmful actions
Enhanced robustness: Better resistance to adversarial inputs and edge cases
Consistent behavior: More reliable and predictable responses across diverse scenarios

The model continues Anthropic's trend toward safer and more secure models, with particular attention to real-world deployment scenarios where reliability and safety are critical.

Prompt Injection Resistance

Opus 4.5 demonstrates substantial improvements in robustness against prompt injection attacks:

Industry-leading defense: Harder to trick with prompt injection than any other frontier model
Real-world security: Better protection against malicious attacks by hackers and cybercriminals
Comprehensive testing: Evaluated against very strong prompt injection attacks developed by Gray Swan
Production-ready security: Appropriate safeguards for enterprise and critical applications

This improvement is particularly important for applications that process untrusted inputs or operate in environments where security is a primary concern. The enhanced prompt injection resistance makes Opus 4.5 suitable for a broader range of production use cases.

Developer Platform Updates

Advanced Context Management

The Claude Developer Platform introduces new capabilities for managing long-running agent tasks:

Context compaction: Automatic summarization of earlier context to maintain conversation flow
Memory tools: Advanced memory management for extended agent sessions
Subagent coordination: Tools for managing teams of coordinated subagents
Task persistence: Infrastructure for maintaining state across long-running workflows

These capabilities enable developers to build more sophisticated agent systems that can handle complex, multi-step tasks over extended periods without hitting context limits or losing coherence.

Enhanced Tool Use

Opus 4.5 demonstrates improved tool use capabilities:

Fewer tool calling errors: Early users report 50% to 75% reductions in both tool calling errors and build/lint errors
Better tool coordination: More reliable execution of complex tool sequences
Efficient tool usage: Uses tools more effectively, requiring fewer attempts to achieve goals
Advanced tool integration: Better handling of complex tool ecosystems

These improvements make Opus 4.5 particularly effective for agentic workflows that rely heavily on external tools and APIs.

Product Updates

Claude Code Enhancements

Claude Code receives significant upgrades with Opus 4.5:

Plan Mode Improvements:

More precise planning: Builds more accurate and comprehensive plans
Thorough execution: Executes plans more completely and reliably
Clarifying questions: Asks upfront questions to ensure understanding
User-editable plans: Creates editable plan.md files before execution

Desktop App Integration:

Multiple sessions: Run multiple local and remote sessions in parallel
Parallel agents: Different agents can work on different tasks simultaneously
Better organization: Improved management of multiple coding sessions

These updates make Claude Code more powerful and flexible for complex coding projects that require planning, coordination, and parallel execution.

Consumer App Improvements

Significant updates to Claude consumer applications:

Long Conversations:

No context walls: Long conversations automatically summarize earlier context as needed
Seamless continuation: Keep chats going without hitting context limits
Smart summarization: Maintains important context while managing length

Claude for Chrome:

Full availability: Now available to all Max users
Cross-tab functionality: Handles tasks across multiple browser tabs
Enhanced integration: Better coordination with web applications

Claude for Excel:

Expanded beta: Now available to all Max, Team, and Enterprise users
Financial modeling: Improved accuracy and efficiency for complex spreadsheets
Automation capabilities: Better handling of Excel automation tasks

Usage Limits:

Removed Opus caps: Opus-specific usage caps removed for Opus 4.5 users
Increased limits: Max and Team Premium users get roughly the same number of Opus tokens as previously with Sonnet
Daily work support: Limits updated to support using Opus 4.5 for daily work

These updates make Opus 4.5 more practical for everyday use, removing barriers that previously limited access to frontier AI capabilities.

Customer Feedback and Early Results

Industry Testimonials

Early customers report significant improvements across various use cases:

Development Tools:

Cursor: Notable improvement over prior Claude models with better pricing and intelligence on difficult coding tasks
GitHub Copilot: Surpasses internal coding benchmarks while cutting token usage in half (as reported by GitHub)
Warp Terminal: 15% improvement on Terminal Bench with better long-horizon autonomous tasks (as reported by Warp)

Enterprise Applications:

Lovable: Frontier reasoning in chat mode transforms planning and code generation
Notion Agent: First time making Opus available, excelling at interpreting user intent
Office automation: Agents autonomously refine capabilities, achieving peak performance in 4 iterations

Specialized Use Cases:

Financial modeling: 20% accuracy improvement and 15% efficiency increase on Excel automation (as reported by Coefficient)
3D visualization: Only model that handles hardest 3D visualizations with 75% time reduction (as reported by Spline)
Code review: Catches more issues without sacrificing precision (as reported by CodeRabbit)
SQL workflows: Dynamic rather than overthinking, dramatically more efficient (as reported by Defog)

These testimonials highlight the practical value that Opus 4.5 delivers across diverse applications, from coding to office automation to specialized professional tasks.

Performance Metrics

Early testing reveals consistent performance improvements:

Token efficiency: Early users report 50% to 75% reductions in both tool calling errors and build/lint errors
Task completion: Consistently finishes complex tasks in fewer iterations
Reliability: More reliable execution with fewer dead-ends
Speed: Remarkable speed improvements noted by multiple users
Quality: Higher pass rates on held-out tests while using fewer tokens (up to 65% fewer tokens in some cases)

These metrics demonstrate that Opus 4.5 doesn't just improve on individual benchmarks, but delivers real-world value through better efficiency, reliability, and quality.

Technical Evaluation Results

Internal Benchmark Performance

Anthropic's internal testing reveals impressive capabilities:

Performance Engineering Test:

Human-level performance: Within a 2-hour time limit, scored higher than any human candidate ever (using parallel test-time compute)
Without time limit: Matched the best-ever human candidate when used within Claude Code (without time limit)
Technical assessment: Demonstrates strong technical ability and judgment under pressure

This result raises important questions about how AI capabilities are changing professional skill requirements and evaluation methods. The model's ability to match or exceed human performance on technical assessments represents a significant milestone.

Creative Problem-Solving

Opus 4.5 demonstrates creative approaches to complex problems:

Example: Airline Policy Challenge:

Creative solution: Found a clever path around policy constraints by changing cabin class first, then flights
Unconventional thinking: Identified solutions that weren't anticipated in benchmark design
Practical value: This type of creative problem-solving is exactly what makes Opus 4.5 valuable

While some creative solutions might technically score as failures in rigid benchmarks, they represent the kind of practical problem-solving that users value in real-world applications.

Benchmark Comparisons

Opus 4.5 shows strong performance across multiple evaluation frameworks:

SWE-bench Verified: State-of-the-art performance on real-world software engineering
Terminal Bench: 15% improvement over Sonnet 4.5 in autonomous terminal tasks (as reported by Warp)
Deep research: Nearly 15 percentage point improvement (from 70.48% to 85.30%) on a fetch-enabled version of BrowseComp-Plus when using advanced techniques like context management and memory capabilities
Internal evaluations: Strong performance across diverse enterprise task benchmarks

These results demonstrate that Opus 4.5's improvements are consistent across different types of tasks and evaluation methods.

Why This Matters

Democratizing Frontier AI

The combination of improved performance and reduced pricing makes frontier AI more accessible:

Broader access: More developers, teams, and enterprises can now use Opus-level capabilities
Cost efficiency: Better performance at lower costs enables more use cases
Practical deployment: Efficiency improvements make production deployment more viable
Innovation enablement: Lower barriers to entry support more experimentation and innovation

This accessibility is crucial for the broader adoption of advanced AI capabilities across industries and use cases.

Advancing AI Capabilities

Opus 4.5 represents meaningful progress in AI system capabilities:

Real-world performance: State-of-the-art results on practical benchmarks, not just academic tests
Efficiency gains: Better results with fewer resources represents genuine capability advancement
Safety improvements: Better alignment and security without sacrificing capability
Practical integration: Updates make advanced AI more usable in everyday workflows

These advances demonstrate that AI development is progressing not just in raw capability, but in practical usability, efficiency, and safety.

Industry Impact

The release has implications for the broader AI industry:

Competitive positioning: Sets new standards for coding and agent capabilities
Pricing trends: Reduced pricing may influence industry pricing strategies
Developer tools: New controls and capabilities influence developer tool development
Use case expansion: Better efficiency and lower costs enable new use cases

As one of the leading frontier models, Opus 4.5's improvements and pricing will likely influence the direction of the broader AI industry.

Conclusion

Claude Opus 4.5 represents a significant advancement in AI capabilities, particularly for coding, agents, and computer use. With state-of-the-art performance on real-world software engineering benchmarks, dramatic improvements in efficiency, and reduced pricing, Opus 4.5 makes frontier AI capabilities more accessible and practical than ever before.

The introduction of the effort parameter gives developers new levels of control over efficiency and capability tradeoffs, while updates to Claude Code, Claude for Chrome, Claude for Excel, and the desktop app make advanced AI more integrated into everyday workflows. The model's improvements in safety, prompt injection resistance, and alignment ensure that these enhanced capabilities come with appropriate safeguards.

Key Takeaways:

Coding excellence: State-of-the-art performance on SWE-bench Verified, the best model for real-world software engineering
Efficiency breakthrough: 76% fewer tokens at medium effort while matching Sonnet 4.5's best performance
Accessible pricing: $5/$25 per million tokens makes Opus-level capabilities available to more users
Enhanced safety: Most robustly aligned Anthropic model with industry-leading prompt injection resistance
Practical integration: Updates to Claude Code, Chrome, Excel, and desktop apps make advanced AI more usable
Developer control: New effort parameter enables optimization of efficiency vs capability tradeoffs

This development highlights that AI systems are becoming more capable, efficient, and practical for real-world applications. The combination of superior performance, improved efficiency, reduced costs, and better integration makes Claude Opus 4.5 a transformative platform for developers, enterprises, and users who want to leverage the best AI capabilities available.

Explore more about Claude models in our models catalog, learn about AI agents in our glossary, or discover AI coding tools in our AI tools directory.