{"exportVersion":1,"sourceSchemaVersion":1,"feedAsOf":"2026-09-30","selection":{"providerId":"anthropic","category":"all"},"feedUrl":"https://stackreplay.com/changelog/feed.json?provider=anthropic","items":[{"url":"https://stackreplay.com/changelog/claude-sonnet-4-5-deprecated","categories":["models"],"event":{"id":"claude-sonnet-4-5-deprecated","type":"model_retirement","importance":"minor","occurredAt":"2026-09-30","dateBasis":"provider_publication_date","effectiveAt":"2026-11-30","discoveredAt":"2026-09-30","verifiedAt":"2026-09-30","providerId":"anthropic","modelIds":["claude-sonnet-4-5"],"planIds":[],"title":"Claude Sonnet 4.5 deprecated","summary":"Anthropic notified API developers that Claude Sonnet 4.5 retires on November 30, 2026, with Claude Sonnet 5.5 as the recommended replacement.","status":"scheduled","sources":[{"url":"https://platform.claude.com/docs/en/about-claude/model-deprecations","title":"Model deprecations - Claude Platform Docs","authority":"first_party","checkedAt":"2026-09-30","excerpt":"2026-09-30: Claude Sonnet 4.5 model On September 30, 2026, Anthropic notified developers using Claude Sonnet 4.5 of its upcoming retirement on the Claude API. Retirement date November 30, 2026 claude-sonnet-4-5-20250929 claude-sonnet-5-5"}]}},{"url":"https://stackreplay.com/changelog/claude-sonnet-5-5-released","categories":["models"],"event":{"id":"claude-sonnet-5-5-released","type":"model_release","importance":"major","occurredAt":"2026-09-28","dateBasis":"provider_publication_date","discoveredAt":"2026-09-30","verifiedAt":"2026-09-30","providerId":"anthropic","modelIds":["claude-sonnet-5-5"],"planIds":[],"benchmark":{"sourceSetIds":["anthropic-sonnet-2026-09-28"],"benchmarkIds":[],"headlineBenchmarkId":"terminal-bench-4-0"},"title":"Claude Sonnet 5.5 released","summary":"Anthropic's new mid-tier model, priced the same as Sonnet 5 and available on the Claude API, Amazon Bedrock, Google Cloud and Microsoft Foundry.","status":"available","sources":[{"url":"https://www.anthropic.com/claude-sonnet-5-5","title":"Introducing Claude Sonnet 5.5","authority":"first_party","checkedAt":"2026-09-30","excerpt":"Sonnet 5.5 is priced the same as Sonnet 5 at $2 per million input tokens, $10 per million output tokens, and $0.20 per million tokens for cache reads, but it typically needs far fewer tokens to do the same work."},{"url":"https://platform.claude.com/docs/en/about-claude/model-deprecations","title":"Model deprecations - Claude Platform Docs","authority":"first_party","checkedAt":"2026-09-30","excerpt":"claude-sonnet-5-5 Active N/A Not sooner than September 28, 2027"}]}},{"url":"https://stackreplay.com/changelog/anthropic-sonnet-5-5-results","categories":["benchmarks"],"event":{"id":"anthropic-sonnet-5-5-results","type":"benchmark_update","importance":"minor","occurredAt":"2026-09-28","dateBasis":"provider_publication_date","discoveredAt":"2026-09-30","verifiedAt":"2026-09-30","providerId":"anthropic","modelIds":["claude-sonnet-5-5"],"planIds":[],"benchmark":{"sourceSetIds":["anthropic-sonnet-2026-09-28"],"benchmarkIds":[],"headlineBenchmarkId":"terminal-bench-4-0"},"title":"Anthropic publishes Claude Sonnet 5.5 launch results","summary":"Anthropic's launch results for Sonnet 5.5 include Terminal-Bench 4.0, where it reports 70.6% against Sonnet 5's 10.3%.","status":"effective","sources":[{"url":"https://www.anthropic.com/claude-sonnet-5-5","title":"Introducing Claude Sonnet 5.5","authority":"first_party","checkedAt":"2026-09-30","excerpt":"Sonnet 5.5 scores 70.6% on Terminal-Bench 4.0, an agentic coding evaluation, compared to Sonnet 5’s 10.3%."}]}},{"url":"https://stackreplay.com/changelog/claude-opus-5-5-released","categories":["models"],"event":{"id":"claude-opus-5-5-released","type":"model_release","importance":"major","occurredAt":"2026-09-22","dateBasis":"provider_publication_date","discoveredAt":"2026-09-30","verifiedAt":"2026-09-30","providerId":"anthropic","modelIds":["claude-opus-5-5"],"planIds":[],"title":"Claude Opus 5.5 released","summary":"Anthropic's new flagship. Input and output cost 20% less than Opus 5, and cache reads, most of the cost of agentic coding, 60% less.","status":"available","sources":[{"url":"https://www.anthropic.com/claude-opus-5-5","title":"Introducing Claude Opus 5.5","authority":"first_party","checkedAt":"2026-09-30","excerpt":"Input and output tokens are $4 and $20 per million, 20% less than Opus 5. Cache reads (which make up the majority of agentic and coding work costs) are $0.20 per million tokens, 60% less than Opus 5."},{"url":"https://platform.claude.com/docs/en/release-notes/api","title":"Claude API Release Notes","authority":"first_party","checkedAt":"2026-09-30","excerpt":"September 22, 2026 ... On Claude Opus 5.5, thinking can't be disabled: thinking: {\"type\": \"disabled\"} and thinking: {\"type\": \"enabled\", ...} return a 400 error."}]}},{"url":"https://stackreplay.com/changelog/claude-five-hour-limits-raised","categories":["subscriptions"],"event":{"id":"claude-five-hour-limits-raised","type":"plan_limit_change","importance":"notable","occurredAt":"2026-09-22","dateBasis":"provider_publication_date","discoveredAt":"2026-09-30","verifiedAt":"2026-09-30","providerId":"anthropic","modelIds":[],"planIds":["anthropic-claude-pro","anthropic-claude-max-5x","anthropic-claude-max-20x"],"title":"Claude raises five-hour usage limits on paid plans","summary":"Alongside Opus 5.5, Anthropic increased five-hour usage limits on Pro, Max, Team and seat-based Enterprise plans, and gave subscribers a rate-limit reset they can save and use later.","status":"effective","sources":[{"url":"https://www.anthropic.com/claude-opus-5-5","title":"Introducing Claude Opus 5.5","authority":"first_party","checkedAt":"2026-09-30","excerpt":"In addition to the price drop, we're increasing five-hour usage limits on Pro, Max, Team, and seat-based Enterprise plans. We're also providing subscription users a rate limit reset, which you can now save and use whenever you choose."}]}},{"url":"https://stackreplay.com/changelog/claude-fable-5-1-released","categories":["models"],"event":{"id":"claude-fable-5-1-released","type":"model_release","importance":"notable","occurredAt":"2026-09-01","dateBasis":"provider_publication_date","discoveredAt":"2026-09-30","verifiedAt":"2026-09-30","providerId":"anthropic","modelIds":["claude-fable-5-1"],"planIds":[],"title":"Claude Fable 5.1 released","summary":"A new Claude Fable release with a 1M-token context window and 128K maximum output.","status":"available","sources":[{"url":"https://platform.claude.com/docs/en/models/fable-5-1/overview","title":"Claude Fable 5.1 - Claude Platform Docs","authority":"first_party","checkedAt":"2026-09-30","excerpt":"Claude Fable 5.1 This model 1M 128K $10 / $50 Slower Adaptive (always on) high Jun 2026 ... Released September 1, 2026 Retirement Not sooner than September 1, 2027"}]}}]}