01 · Operational consequence
Lifecyclecompleted
Severitycritical
ConsequenceThis date applies to Anthropic-operated platforms. Bedrock and Google Cloud schedules may differ.
02 · Affected subjects
Componentsclaude-opus-4-1-20250805 on the Claude API
AudienceClaude API customers whose applications still call the dated Opus 4.1 model ID.
RegionClaude API, Claude Platform on AWS and Microsoft Foundry; partner-operated platform schedules differ
03 · Detection
Stable event IDksr-anthropic-claude-opus-4-1-2026-08-05
Change typeretirement
04 · Before → after
BeforeDeprecated until August 5, 2026
AfterRetired
05 · Required action
ActionRemove claude-opus-4-1-20250805 from production configuration, migrate to Claude Opus 5, and regression-test behavior, latency, token use and cost.
Replacement or migration pathReplace claude-opus-4-1-20250805 with claude-opus-5, review current model migration guidance, and validate prompts, tool calls, safety behavior, latency and cost before full cutover.
06 · Actionable date
Date roleMigration deadline
Date2026-08-05
Statuscompleted
07 · Kingy reproduction
StatusNot tested
LimitationsSource evidence reviewed; no paid vendor call or production reproduction was run.
08 · Sources and revision
Checked2026-09-04
Official sourceshttps://platform.claude.com/docs/en/release-notes/overview · https://platform.claude.com/docs/en/about-claude/model-deprecations · https://platform.claude.com/docs/en/about-claude/models/migration-guide
Correction history2026-08-23: Post-deadline verification changed the record from scheduled retirement to retired and unavailable.