Claude Opus 4.6 vs 4.5: What’s New in Coding & Agent Teams?

Anthropic just dropped Claude Opus 4.6 and it is a massive shift in how we think about AI in our development workflow. While Opus 4.5 was already a powerhouse, 4.6 is being described as the first model designed for the Vibe working era. This comparison covers exactly what has changed from the 1 million token context window to the new agent teams feature that lets you run parallel sub agents on your codebase. If you have been struggling with context rot or models that lose context on large projects, this update is specifically for you.

The jump from 4.5 to 4.6 is statistically significant in the GDP while EE evaluation, which measures economically valuable knowledge work. OPUS 4.6 outperformed OPUS 4.5 by 190 ELO points. It also leads the industry on Terminal Benchmark 2.0 for agentic coding. The real headline is a 1 million token context window in beta.

Comparison Point	Claude Opus 4.6	Claude Opus 4.5
Context window	1 million token context window in beta	No 1 million token context window
Adaptive thinking	Yes - picks up on contextual clues to decide how much reasoning is needed	Not available
Effort parameter	Yes - low to max to balance speed and cost	Not available
Agent teams	Research preview - spin up multiple agents that work in parallel	Not available
Terminal Benchmark 2.0	65.4	59.88
Pricing (standard)	Input $5 per million tokens, output $25 per million tokens	Input $5 per million tokens, output $25 per million tokens
1M context premium pricing	Prompts exceeding 200k tokens: input $10, output $37.5	Not applicable
Context compaction	Beta - automatically summarizes older parts of the conversation	Not available
Debugging unfamiliar code bases	Noticeably better at debugging and exploring unfamiliar code bases	Weaker here based on testing notes
Hands-on Angular test result	Ran successfully, added statistics and filters, used a modal for Add User, more modern design	Had trouble starting, used a new route for Add User, simpler design

Claude Opus 4.6 vs 4.5: What’s New in Coding & Agent Teams?

The Technical Breakdown

OPUS 4.6 outperformed OPUS 4.5 by 190 ELO points on GDP while EE evaluation, which measures economically valuable knowledge work. It also leads on Terminal Benchmark 2.0 for agentic coding.

The 1 million token context window is in beta. On the eight needle 1 million variant test, OPUS 4.6 scored 76% while Sonet 4.5 only hit 18.5%. This means it can actually find that one specific bug hidden in a massive codebase without the performance degrading as the conversation gets longer.

We also have adaptive thinking. Instead of just turning the model’s thinking on or off, it picks up on contextual clues to decide how much reasoning is needed. You can control this with a new effort parameter ranging from low to max to balance speed and cost.

Agent Teams and Claude Code

The most exciting feature for me is agent teams. This is currently in research preview and it allows you to spin up multiple agents that work in parallel. Imagine one agent reviewing your database logic while another handles the front-end refactoring and all coordinated autonomously.

In real world testing, companies like Rakuten reported results like closing 13 issues and assigning 12 others in a single day across six repositories. For those of us using IDEs like Windsurf, Jeff Wong noted that 4.6 is noticeably better at debugging and exploring unfamiliar code bases because it thinks longer and more carefully before settling on an answer. If it starts overthinking simple tasks, you just dial the effort down to medium or low.

Claude Opus 4.6 vs 4.5: What’s New in Coding & Agent Teams? Availability and Pricing

It is available in the Claude application, the API, and in Cursor. In Cursor, update to see Opus 4.6 or add models and select Opus 4.6. It is also available in Windsurf, where the latest update has Opus 4.6 ready to select.

Pricing remains consistent with Opus 4.5 at $5 per million tokens input and $25 per million tokens output. If you use the 1 million token context window, premium pricing applies for prompts exceeding 200k tokens, which goes up to $10 for input and $37.5 for output. Context compaction is in beta, which automatically summarizes older parts of the conversation so you do not hit those limits as quickly during long running tasks.

Claude Opus 4.6 vs 4.5: What’s New in Coding & Agent Teams? Hands-On Coding Results

Setup and Approach

I ran a head-to-head in Windsurf’s Arena mode on an Angular application generated with Angular CLI. The prompt was to generate a user management dashboard in Angular following best practices. I selected Claude Opus 4.6 and Claude Opus 4.5 to run side-by-side and compared both the code and the live apps.

What I Saw in the Code

• Both produced a user service and a user model with fields like first name, last name, roles, and statuses.
• Mocked users were generated, the service used inject syntax, queries, and basic CRUD.
• The Angular code looked fine: signals, injectors, change detection push, and provider setup were in place.

Running the Apps

• Opus 4.6 ran successfully. Opus 4.5 had trouble starting at first.
• The 4.6 app showed a user management UI with Add User, validations, roles and statuses, edit and delete, search, and filtering and sorting.
• The 4.6 app added statistics and filters, and used a modal for adding users, which felt more natural for a small form.
• The 4.5 app produced almost the same application but used a new route for the Add User flow. The 4.6 design looked a bit more modern.

Claude Opus 4.6 vs 4.5: What’s New in Coding & Agent Teams? Benchmarks and Impressions

• Terminal Benchmark 2.0: Opus 4.6 at 65.4 vs Opus 4.5 at 59.88, which I called about 5 to 6 percent better.
• If you were using Sonet 4.5 a lot, there is almost a 15 percent difference in the results I referenced.
• In other comparisons, GPT 5.2 and Opus 4.6 looked similar with less than a 1 percent difference based on the chart I saw.
• Multiple companies are publicly excited about 4.6, including Box, Figma, and Shopify.

Features Breakdown for Claude Opus 4.6

• 1 million token context window in beta
• Adaptive thinking that decides how much reasoning is needed
• Effort parameter from low to max to balance speed and cost
• Agent teams in research preview for parallel sub agents on your codebase
• Context compaction in beta to summarize older parts of long conversations
• Noticeably better at debugging and exploring unfamiliar code bases
• Strong results on Terminal Benchmark 2.0 and the needle-in-a-haystack style 1M variant test

Features Breakdown for Claude Opus 4.5

• Strong general coding performance
• Consistent pricing at $5 per million tokens input and $25 per million tokens output
• Solid results on Terminal Benchmark 2.0 compared to the field
• Familiar workflows for teams already using Opus 4.5

Pros and Cons: Claude Opus 4.6

Pros

• Massive jump in capability with a 1 million token context window in beta
• Adaptive thinking plus an effort control to tune speed, cost, and depth
• Agent teams to run multiple coordinated agents in parallel
• Better at debugging and exploring unfamiliar code bases
• Context compaction helps keep long tasks within token limits
• Strong benchmark performance and real world productivity reports

Cons

• 1M context premium pricing applies beyond 200k tokens
• Agent teams is still in research preview
• Can overthink simple tasks unless you dial the effort down

Pros and Cons: Claude Opus 4.5

Pros

• Proven and stable for many coding workflows
• Same base pricing structure as 4.6 for standard contexts
• Solid benchmark scores and familiar behavior

Cons

• Lower performance on key benchmarks compared to 4.6
• No 1 million token context window
• No adaptive thinking or effort parameter
• No agent teams and parallel sub agent coordination
• In my test, the app was slower to start and the UI felt less modern

Use Cases: Where Each Option Excels

Claude Opus 4.6

• Large projects that suffer from context rot
• Long-running conversations and deep code reviews
• Teams that want to coordinate multiple specialized agents
• Debugging unfamiliar code bases where careful reasoning pays off
• Developers who want to tune depth and cost with the effort parameter

Claude Opus 4.5

• Smaller projects and short tasks that do not need huge context
• Teams that prefer a simpler, stable setup with familiar behavior
• Cost-conscious prompts that do not cross 200k tokens

Final Conclusion

Claude Opus 4.6 is not an incremental update. It is a shift toward truly autonomous software engineering with better code review, a 1 million token context window, adaptive thinking with a controllable effort parameter, and the ability to coordinate teams of agents. Benchmarks, hands-on coding, and early user reports point to meaningful gains over Opus 4.5.

Choose Opus 4.6 if you need the 1M context, adaptive thinking, agent teams, or better debugging on unfamiliar code. Stay with Opus 4.5 if your tasks are short, your context demands are modest, and you want the same pricing without the premium for very large prompts.