Claude Code: New "Fast Mode" accelerates AI model Opus 4.6

As the provider Anthropic announces in its official documentation, the new "Fast Mode" is aimed at subscribers as well as users of the Claude Console. Billing is done as additional usage.

The "Fast Mode" can be activated either via the command /fast in the Claude Code command line or directly in the associated VS Code extension. Alternatively, the mode can be permanently activated by entering "fastMode": true in the user settings file, Anthropic describes.

A confirmation message – "Fast mode ON" – and a lightning bolt symbol (↯) next to the prompt signal the active state. If another AI model is in use, Claude Code automatically switches to Opus 4.6. With a new input of /fast, the status can be checked at any time.

Costs and Availability

According to the documentation, the "Fast Mode" for Opus 4.6 starts at $30 per 150 million tokens. At the launch of the feature, a 50 percent introductory discount on all plans will be granted until February 16th. The costs are billed as an additional service and do not affect the rate limits included in the subscriptions.

The mode is available to all users with a Pro, Max, Team, or Enterprise subscription, as well as to customers of the Claude Console API. However, the fast mode is not available on third-party cloud platforms such as Amazon Bedrock, Google Vertex AI, or Microsoft Azure.

The prerequisite for use is the activation of the option for additional costs ("additional usage"), which allows billing beyond the quota included in the plan. While individual account holders can make this setting themselves in the console's billing options, for team and enterprise accounts, an administrator must enable the feature for the entire organization.

By default, "Fast Mode" is deactivated for organizations with Team and Enterprise plans and must be explicitly activated by the administrator. The corresponding configuration can be found for API customers in the Claude Code preferences of the console and for Team and Enterprise customers in the administrator settings under "Claude Code".

Recommended Use Cases

The provider recommends using "Fast Mode" particularly for use cases where speed is critical. These include rapid iteration on code changes, live debugging sessions, and time-sensitive projects with tight deadlines.

On the other hand, the mode is less suitable for long-running, autonomous tasks where execution speed plays a subordinate role. It is also not recommended for batch processing, use in CI/CD pipelines, a method to improve software delivery during the software development lifecycle through automation, or for particularly cost-sensitive workloads.

If users reach their plan's rate limits, "Fast Mode" automatically switches to the standard speed of Opus 4.6. A grayed-out lightning bolt symbol (↯) signals this temporary cooldown phase. Work can then continue at regular prices until the fast mode reactivates itself after the period has expired.

The provider labels the feature as "Research Preview". This implies that the feature may still change based on user feedback. The availability, pricing, and underlying API configuration are also not final and may change in the future.

(tho)