HighDeprecation
Claude Sonnet 4.5/4 1M-token context window retired — migrate to Sonnet 4.6 or Opus 4.6
Action Required
Applications using 1M-context in Sonnet 4.5/4 will fail for prompts >200k tokens and must migrate to Sonnet 4.6 or Opus 4.6 to avoid disruption.
AI Impact Summary
An experimental 1M-token context window for Claude Sonnet 4.5/4 has been retired. Requests exceeding 200k tokens will error unless migrated to Claude Sonnet 4.6 or Claude Opus 4.6, which offer the 1M-context option under standard pricing. Plan to route high-token workloads to the 4.6 family, remove any beta-context headers, and update monitoring to flag 200k+ token errors and verify correct routing in CI/CD and production.
Claude Sonnet 4.5/4 1M-token context window retired — migrate to Sonnet 4.6 or Opus 4.6
Affected Systems
Claude Sonnet 4.5
- Date
- Date not specified
- Change type
- deprecation
- Severity
- high