How do you troubleshoot manual extended thinking left over from Sonnet 4.6?

Locate every place in the codebase where a request sets thinking: {"type": "enabled", "budget_tokens": N}, since this specific configuration is rejected outright on Sonnet 5 with an HTTP 400 error - this is a search-and-remediate task rather than a subtle behavioral issue, since the failure mode is a hard, deterministic error rather than degraded output.

Replace each instance by removing the manual budget_tokens configuration and instead setting an appropriate effort level for that specific request's typical task difficulty, recognizing that effort and a manual token budget aren't a one-to-one mapping - a budget value that was tuned empirically for Sonnet 4.6 doesn't translate directly to a specific effort level on Sonnet 5.

Test each remediated request type against representative tasks to confirm the new effort-based configuration produces comparable or better reasoning depth to what the old manual budget achieved, since silently under-provisioning reasoning depth by picking too low an effort level would be a functional regression even though it wouldn't surface as an obvious error.

Audit for any downstream code that specifically expected a fixed thinking-token count based on the old manual budget, such as cost estimation logic or logging that assumed a predictable thinking-token ceiling, since that logic likely also needs updating now that thinking token usage varies adaptively rather than being pinned to a configured fixed value.