{"version":"2.0.5","anchor":"extended-thinking-support-for-sonnet-4-5","canonical_anchor":"extended-thinking-support-for-sonnet-4-5","heading":"Extended Thinking Support for Sonnet 4.5","tier":null,"area":null,"scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.0.5\/e\/extended-thinking-support-for-sonnet-4-5","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.0.5","markdown":"### Extended Thinking Support for Sonnet 4.5\n\n**What:** Claude Code now supports extended thinking mode when using Claude Sonnet 4.5, enabling more transparent reasoning for complex tasks.\n\n**How to use:**\n\n`# Enable thinking via environment variable MAX_THINKING_TOKENS=10000 claude # Or configure in your settings file # Set alwaysThinkingEnabled: true in your Claude Code settings` **Details:**\n\n- Only available when using Claude Sonnet 4.5 model\n- Can be controlled via `MAX_THINKING_TOKENS` environment variable (set to any positive integer to enable)\n- Can be configured permanently via `alwaysThinkingEnabled` in settings\n- Subject to Statsig feature gate `thinking_on_default` for gradual rollout\n- Provides visible reasoning steps during Claude's problem-solving process\n- **Evidence**: `hL1() at line 364041` in v2.0.5"}