Claude Code leverages an advanced “thinking” mode, including the super poweful Ultrathink capability, to enhance its problem-solving, planning, and code generation processes. This feature allows Claude to allocate additional computational resources for deeper analysis, moving beyond superficial responses to deliver more comprehensive and accurate results.

What is Thinking Mode?

Extended thinking mode in Claude Code is a mechanism that allows the AI to perform extended reasoning and evaluate alternatives more thoroughly before producing an output. Instead of immediately generating code or an answer, Claude takes an “analytical pause” to understand the complete context and develop robust strategies. This process is particularly beneficial for complex problems where multiple factors need to be balanced.

When Claude is in a thinking mode, its internal thought process is often displayed as italic gray text in the terminal, providing transparency into its reasoning. This visibility can be invaluable for developers to understand Claude’s approach and guide it effectively.

How to Trigger Thinking Modes

You can activate different levels of thinking by incorporating specific keywords into your prompts:

• “think”: This triggers an initial level of extended thinking, allocating approximately 4,000 tokens for reasoning.
• “think hard” or “megathink”: These phrases prompt Claude to engage in deeper consideration, allocating around 10,000 tokens.
• “think harder” or “ultrathink”: These are the most intense thinking modes, providing Claude with a significant thinking budget of approximately 31,999 tokens to thoroughly evaluate alternatives. “Ultrathink” is considered a powerful prompting technique for particularly challenging problems.

These intensifying phrases direct Claude to dedicate progressively more computational time to its thought process.

Benefits and Use Cases

Employing thinking modes, especially “Ultrathink,” offers several significant advantages for development workflows:

• Improved Instruction Adherence and Reasoning: Extended thinking directly improves Claude’s ability to follow instructions, enhance its reasoning capabilities, and increase overall efficiency.
• Strategic Planning: It is highly recommended to ask Claude to make a plan for approaching a specific problem, utilizing “think” or “think hard” during this phase. This methodical approach ensures alignment between requirements and execution, significantly improving results on complex tasks.
• Complex Problem-Solving and Architectural Decisions: Thinking modes are invaluable for designing scalable architectures, balancing multiple constraints, and making informed decisions in intricate scenarios. Claude 4 models, in particular, show transformative improvement in strategic planning and extended thinking for challenging technical problems.
• Debugging and Refactoring: These modes excel when applied to debugging complex issues and formulating refactoring strategies for large files, improving code maintainability, scalability, and readability.
• Multi-Agent Collaboration: The lead agent in a multi-agent system can use thinking mode to plan its approach, assessing which tools fit the task, determining query complexity, and defining each subagent’s role. Subagents also utilize interleaved thinking after tool results to evaluate quality, identify gaps, and refine their next queries. Combining “Ultrathink” with parallel task execution can dramatically accelerate complex tasks, making workflows much faster.
• Cost Optimization: While extended thinking consumes more tokens initially, it can lead to cost efficiency by reducing the need for repetitive instructions or corrective prompts that arise from Claude going off-track or producing superficial code. A well-thought-out plan derived from thinking mode can ensure consistent and accurate output from the first attempt, saving tokens in the long run.

Best Practices and Considerations

• Context is Key: Claude Code performs significantly better when provided with relevant context. Thinking modes leverage this context to make informed decisions.
• “Explore, Plan, Code, Commit” Workflow: Thinking modes are a critical part of this versatile workflow, particularly during the “Plan” phase, where Claude develops a detailed, step-by-step approach before writing code.
• Human Oversight: Even with advanced thinking, human oversight remains necessary for broader architectural decisions and to “reel Claude back in” if it goes off on tangents.
• Cost Implications: While beneficial, extended thinking is more expensive in terms of token usage. Users with Max plans have more access to powerful models like Opus 4, which is often used with these modes. Some community-driven frameworks like SuperClaude also aim to incorporate token optimization even within thinking modes.