Corrected Claude Sonnet 5 thinking guidance: adaptive thinking is on by default and can be disabled
Corrected the Reasoning entry on the <a href="https://docs.aws.amazon.com/bedrock/latest/userguide/model-card-anthropic-claude-sonnet-5.html">Claude Sonnet 5</a> model card, which incorrectly stated that adaptive thinking is always on and cannot be disabled. On Claude Sonnet 5, adaptive thinking is on by default — including for requests that omit the <code class="code">thinking</code> field — and can be turned off by passing <code class="code">"thinking": <span>{</span>"type": "disabled"}</code>. Added Claude Sonnet 5 to the supported models table on the <a href="https://docs.aws.amazon.com/bedrock/latest/userguide/inference-anthropic-claude-messages-adaptive-thinking.html">Adaptive thinking</a> topic, and added guidance covering the default-on behavior change from Claude Sonnet 4.6, the fact that only the explicit <code class="code">disabled</code> thinking type turns thinking off (omitting the <code class="code">thinking</code> field selects adaptive thinking, and <code class="code">budget_tokens</code> is not supported on this model), that thinking tokens are billed as output tokens, and the need to revisit <code class="code">max_tokens</code> for workloads migrated from Claude Sonnet 4.6.