--- title: "Anthropic API changes, deprecations and deadlines | Harbyn" description: "Anthropic: 1 upcoming deadline and 62 recorded changes as of 2026-10-25, each with its source." canonical: "https://harbyn.com/vendors/anthropic" last-updated: 2026-10-25 --- # Anthropic: API changes and deadlines Markdown version of . AI models and APIs. 1 upcoming deadline, 62 recorded changes. Every entry cites the Anthropic page we read it from. ## What we read The Anthropic pages and feeds our ingestion visits, politely and on a schedule. - **Deprecations**: - **Changelog**: - **Changelog**: - **Changelog**: ## What the scanner looks for How `harbyn scan` recognises Anthropic in a repository, on your machine. Nothing leaves it. - **Packages**: `npm @anthropic-ai/sdk`, `pypi anthropic` - **API hosts**: `api.anthropic.com` - **Model IDs starting with**: `claude-` ## Upcoming deadlines | Deadline | Change | Use instead | Details | Source | | --- | --- | --- | --- | --- | | Nov 30, 2026 | Claude Sonnet 4.5 model: retirement on 2026-11-30 | `claude-sonnet-5-5` | | | ## Change history Newest first, by the date Anthropic announced it. This is the archive: past changes are not warnings, and changes we recorded after they took effect are marked as such. ### October 2026 - Oct 22, 2026, Feature: [Claude Models on Google Cloud (Anthropic managed) launched](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 22, 2026, Feature: [Fast mode available for Claude Opus 5.5 on Anthropic-managed Google Cloud](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 21, 2026, Feature: [API version 2026-10-21 released](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 21, 2026, Breaking change: [SDK and CLI versions include breaking changes](https://harbyn.com/changes/anthropic/2026-10-21-sdk-and-cli-versions-include-breaking-changes.md) - Oct 21, 2026, Feature: [SDK and CLI versions released](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 21, 2026, Feature: [User profiles expose enforcement status and actions](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 20, 2026, Feature: [Inference hooks leave beta](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 20, 2026, Feature: [Organization webhooks added to the Admin API](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 20, 2026, Feature: [User profiles API launched](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 15, 2026, Feature: [Compliance API adds organization user preferences](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 15, 2026, Feature: [Fast mode for Claude Opus 5.5 available on Microsoft Foundry](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 15, 2026, Feature: [Fast mode is generally available for Claude Opus 5.5](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 15, 2026, Feature: [Models API reports between-tools thinking support](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 14, 2026, Feature: [Claude Managed Agents scheduled deployments available on Claude Platform on AWS](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 14, 2026, Feature: [OpenTelemetry export launched in beta](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 9, 2026, Feature: [Dynamic workflows for Claude Managed Agents](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 8, 2026, Feature: [Compliance API can download Claude Docs documents as Word files](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 7, 2026, Behavior change: [Claude Haiku 5.5 rejects manual extended thinking and returns thinking blocks by default](https://harbyn.com/changes/anthropic/2026-10-07-claude-haiku-5-5-behavior-can-break-code-written-for-claude-haiku-4-5.md) - Oct 7, 2026, Feature: [Claude Haiku 5.5 launched](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 7, 2026, Behavior change: [Limited networking applies allowed\_hosts to web tools](https://harbyn.com/changes/anthropic/2026-10-07-limited-networking-applies-allowed-hosts-to-web-tools.md) - Oct 7, 2026, Policy: [Lower prompt cache read price for Claude Sonnet 5.5](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 7, 2026, Feature: [Monthly API credits included with Claude Max and Team plans](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 7, 2026, Feature: [Python and TypeScript SDKs add beta browser and computer use tool classes](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 6, 2026, Feature: [Models API reports server tool capabilities](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 5, 2026, Feature: [Models API reports disabled-thinking support](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 1, 2026, Feature: [Dreams supports additional models](https://platform.claude.com/docs/en/release-notes/overview.md) - Oct 1, 2026, Feature: [Models API responses include a model line field](https://platform.claude.com/docs/en/release-notes/overview.md) ### September 2026 - Sep 30, 2026, Feature: [Admin API organization methods are out of beta](https://platform.claude.com/docs/en/release-notes/overview.md) - Sep 28, 2026, Behavior change: [Claude Sonnet 5.5 rejects five Claude Sonnet 5 request patterns](https://harbyn.com/changes/anthropic/2026-09-28-claude-sonnet-5-5-changes-compatibility-with-claude-sonnet-5-code.md) - Sep 28, 2026, Feature: [Claude Sonnet 5.5 launched](https://platform.claude.com/docs/en/release-notes/overview.md) - Sep 24, 2026, Policy: [Certain pre-output refusals are now billed](https://platform.claude.com/docs/en/release-notes/overview.md) - Sep 24, 2026, Behavior change: [Compliance Activity Feed no longer returns names or titles](https://harbyn.com/changes/anthropic/2026-09-24-compliance-activity-feed-no-longer-returns-names-or-titles.md) - Sep 24, 2026, Feature: [Compliance API local session endpoints leave beta for Microsoft 365 sessions](https://platform.claude.com/docs/en/release-notes/overview) - Sep 23, 2026, Behavior change: [Cache diagnostics is out of beta](https://harbyn.com/changes/anthropic/2026-09-23-cache-diagnostics-is-out-of-beta.md) - Sep 22, 2026, Feature: [Claude Opus 5.5 launched](https://platform.claude.com/docs/en/release-notes/overview) - Sep 22, 2026, Feature: [Launch of Claude Opus 5.5](https://platform.claude.com/docs/en/release-notes/overview.md) (effective Sep 22, 2026; recorded after the fact) - Sep 22, 2026, Feature: [Tools can be defined in mid-conversation system messages](https://platform.claude.com/docs/en/release-notes/overview) - Sep 18, 2026, Feature: [Compliance API local session endpoints return Claude in Chrome session transcripts](https://platform.claude.com/docs/en/release-notes/overview.md) - Sep 18, 2026, Feature: [Compliance local session endpoints add Claude in Chrome transcripts](https://platform.claude.com/docs/en/release-notes/overview) - Sep 14, 2026, Feature: [Messages API adds on-demand conversation compaction](https://platform.claude.com/docs/en/release-notes/overview) - Sep 14, 2026, Feature: [Thinking mismatch transformations can be reported](https://platform.claude.com/docs/en/release-notes/overview) - Sep 10, 2026, Feature: [ant CLI adds session connection command](https://platform.claude.com/docs/en/release-notes/overview) - Sep 10, 2026, Feature: [Claude Managed Agents permission policies auto evaluation](https://platform.claude.com/docs/en/release-notes/overview.md) - Sep 10, 2026, Feature: [Managed Agents permission policies add auto evaluation](https://platform.claude.com/docs/en/release-notes/overview) - Sep 9, 2026, Behavior change: [Fingerprint storage requires the diagnostics object](https://harbyn.com/changes/anthropic/2026-09-09-fingerprint-storage-requires-the-diagnostics-object.md) - Sep 3, 2026, Feature: [ant CLI adds apply command](https://platform.claude.com/docs/en/release-notes/overview) - Sep 1, 2026, Behavior change: [Claude Enterprise Admin, Analytics and Compliance API requests should send the anthropic-version header](https://harbyn.com/changes/anthropic/2026-09-01-enterprise-admin-and-compliance-api-requests-must-send-api-version-header.md) - Sep 1, 2026, Feature: [Thinking display adds updates mode](https://platform.claude.com/docs/en/release-notes/overview) - Sep 1, 2026, Behavior change: [Tool choice restriction on Fable 5.1 and Mythos 5.1](https://harbyn.com/changes/anthropic/2026-09-01-tool-choice-restriction-on-fable-5-1-and-mythos-5-1.md) - Sep 1, 2026, Feature: [Turn-scoped system messages are in beta](https://platform.claude.com/docs/en/release-notes/overview) ### August 2026 - Aug 27, 2026, Deprecation: [SDK beta headers removal for files and skills](https://harbyn.com/changes/anthropic/2026-08-27-sdk-beta-headers-removal-for-files-and-skills.md) ### June 2026 - Jun 9, 2026, Deprecation: [claude-mythos-preview is deprecated](https://harbyn.com/changes/anthropic/2026-06-09-claude-mythos-preview-deprecated.md) - Jun 5, 2026, Retirement: [Claude Opus 4.1 model: retirement on 2026-08-05](https://harbyn.com/changes/anthropic/2026-06-05-claude-opus-4-1-model-retirement.md) (effective Aug 5, 2026; recorded after the fact) ### April 2026 - Apr 14, 2026, Retirement: [Claude Sonnet 4 and Claude Opus 4 models: retirement on 2026-06-15](https://harbyn.com/changes/anthropic/2026-04-14-claude-sonnet-4-and-claude-opus-4-models-retirement.md) (effective Jun 15, 2026; recorded after the fact) ### February 2026 - Feb 19, 2026, Retirement: [Claude Haiku 3 model: retirement on 2026-04-20](https://harbyn.com/changes/anthropic/2026-02-19-claude-haiku-3-model-retirement.md) (effective Apr 20, 2026; recorded after the fact) ### December 2025 - Dec 19, 2025, Retirement: [Claude Haiku 3.5 model: retirement on 2026-02-19](https://harbyn.com/changes/anthropic/2025-12-19-claude-haiku-3-5-model-retirement.md) (effective Feb 19, 2026; recorded after the fact) ### October 2025 - Oct 28, 2025, Retirement: [Claude Sonnet 3.7 model: retirement on 2026-02-19](https://harbyn.com/changes/anthropic/2025-10-28-claude-sonnet-3-7-model-retirement.md) (effective Feb 19, 2026; recorded after the fact) ### August 2025 - Aug 13, 2025, Retirement: [Claude Sonnet 3.5 models: retirement on 2025-10-28](https://harbyn.com/changes/anthropic/2025-08-13-claude-sonnet-3-5-models-retirement.md) (effective Oct 28, 2025; recorded after the fact) ### June 2025 - Jun 30, 2025, Retirement: [Claude Opus 3 model: retirement on 2026-01-05](https://harbyn.com/changes/anthropic/2025-06-30-claude-opus-3-model-retirement.md) (effective Jan 5, 2026; recorded after the fact) ### January 2025 - Jan 21, 2025, Retirement: [Claude 2, Claude 2.1, and Claude Sonnet 3 models: retirement on 2025-07-21](https://harbyn.com/changes/anthropic/2025-01-21-claude-2-claude-2-1-and-claude-sonnet-3-models-retirement.md) (effective Jul 21, 2025; recorded after the fact) ### September 2024 - Sep 4, 2024, Retirement: [Claude 1 and Instant models: retirement on 2024-11-06](https://harbyn.com/changes/anthropic/2024-09-04-claude-1-and-instant-models-retirement.md) (effective Nov 6, 2024; recorded after the fact)