Summary

Anthropic's Claude Opus 4.6 introduces adaptive thinking (thinking.type: "adaptive") as the recommended way to use extended thinking. The previous thinking.type: "enabled" + budget_tokens approach is deprecated on Opus 4.6 and will be removed in a future model release.

OpenClaw currently only supports the deprecated format. There is no way to use adaptive thinking or the new effort parameter (low | medium | high | max).

Why it matters

• The deprecated thinking API will eventually break on newer Anthropic models.
• Adaptive thinking lets the model decide when and how deeply to reason, which improves cost efficiency and enables automatic interleaved thinking between tool calls -- especially useful for agentic workflows.
• The effort parameter gives users a cleaner control surface than fixed token budgets.

References

• Adaptive thinking docs
• Effort parameter docs
• Related: [Feature]: Support for Anthropic Opus 4.6 #9811 (add Opus 4.6 to model registry)