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Anthropic

Claude Platform Release notes from Anthropic

78 releases ยท 21 this month

Official notes RSS
DateRelease
Sep 22Claude API beta lets tools be defined inside mid-conversation system messages
Beta
Sep 22Fast mode research preview available for Claude Opus 5.5 on the Claude API
Preview
Sep 22Claude Opus 5.5 breaking changes: thinking can't be disabled, forced tool_choice removed
Update
Sep 22Claude Opus 5.5 launches with a 1M token context window and 128k output
GA
Sep 18Compliance API adds Claude in Chrome session transcripts in beta
Beta
Sep 14Claude API input_transformations adds thinking_mismatch_allowed entries in beta
Beta
Sep 14Messages API adds on-demand conversation compaction in beta
Beta
Sep 10Claude Managed Agents permission policies add an auto mode
Update
Sep 10ant CLI 1.32.0 adds sessions connect for live Managed Agents sessions
Beta
Sep 3Per-message effort changes beta expands to Claude on Google Cloud
Beta
Sep 3ant CLI 1.30.0 adds ant apply to manage agents and resources as code
Update
Sep 1Claude API adds turn-scoped system messages in beta
Beta
Sep 1Claude API thinking.display adds an updates mode in beta
Beta
Sep 1Claude Enterprise Admin, Analytics and Compliance API guides add anthropic-version
Update
Sep 1Claude Fable 5.1 and Mythos 5.1 require 30-day data retention
Update
Sep 1Claude Fable 5.1 output carries text watermarks and C2PA Content Credentials
Update
Sep 1Per-message effort changes enter beta on the Claude API
Beta
Sep 1Claude Fable 5.1 and Mythos 5.1 reject tool_choice any and tool
Update
Sep 1Claude Fable 5.1 launches alongside Claude Mythos 5.1 with 1M token context
GA
Sep 1Claude Fable 5.1 thinking blocks only replay to the same or newer models
Update
Sep 1Prompt cache reads on Claude Fable 5.1 and Mythos 5.1 drop to $0.25 per MTok
Pricing
Aug 27Claude Console adds personal and service account API keys
Update
Aug 27Claude SDKs stop sending beta headers for Files and Skills clients
Update
Aug 26Admin API comes to the ant CLI and Claude SDKs under client.beta.organization
Beta
Aug 26Compliance API adds Claude Science and Microsoft 365 session transcripts in beta
Beta
Aug 20Claude Python SDK v1.0 moves to httpx2 and requires Python 3.10
Update
Aug 20Claude computer use and browser use toolsets arrive on Google Cloud
Update
Aug 19Claude Console session viewer redesigned with timeline and Inspector panel
Update
Aug 19Claude Managed Agents self-hosted sandboxes can attach memory stores
Update
Aug 19Agent Skills and the Skills API are out of beta on the Claude API
GA
Aug 19Claude API launches browser_toolset_20260801 browser use tool
Update
Aug 19Claude Enterprise Admin API user-management endpoints are out of beta
GA
Aug 19Claude Managed Agents can restrict domains for web_search and web_fetch
Update
Aug 19Computer and browser use toolsets support Claude Fable 5, Opus 5 and Sonnet 5
Update
Aug 19Files API is out of beta on the Claude API
GA
Aug 19Claude computer use tool is out of beta as computer_toolset_20260801
GA
Aug 18Claude Console Workbench is renamed playground
Update
Aug 11Claude API adds the anthropic-workspace-id response header
Update
Aug 10Claude Sonnet 5 introductory pricing of $2 / $10 per MTok becomes permanent
Pricing
Aug 7Claude Managed Agents adds inference_geo to control where inference runs
Update
Aug 7Claude Managed Agents sessions can consult an advisor model
Update
Aug 7Claude Managed Agents sessions load skills from GitHub repositories
Update
Aug 7Claude Managed Agents sessions support hard spend budgets
Pricing
Aug 5Claude Opus 4.1 is retired on the Claude API
Deprecation
Aug 5Inference hooks
Beta
Aug 3Compliance API returns cloud Cowork session transcripts in beta
Beta
Aug 1Dreams research preview adds support for Claude Opus 5
Preview
Jul 24Claude API fallbacks parameter adds a default mode for recommended fallbacks
Beta
Jul 24Fast mode removed for Claude Opus 4.7
Deprecation
Jul 24Mid-conversation tool changes enter beta on the Claude API
Beta
Jul 24Claude Opus 5 launches with a 1M token context window at $5 / $25 per MTok
GA
Jul 24Claude Opus 5 only allows disabling thinking at effort high or below
Update
Jul 24Effort is the primary control for Claude Opus 5
Update
Jul 22Claude Managed Agents agent updates no longer require a version field
Update
Jul 22Claude Managed Agents sessions can be seeded with initial events
Update
Jul 22Claude Managed Agents thread event streams support event deltas
Update
Jul 22Claude Managed Agents agents accept an effort level in model configuration
Update
Jul 22Claude Managed Agents webhooks cover environment and memory store lifecycle
Update
Jul 17Claude experimental prompt tools APIs retire with the Workbench on August 17, 2026
Deprecation
Jul 17Legacy Claude Console Workbench sunsets on August 17, 2026
Deprecation

Summaries of vendors' own notes. Product names and logos belong to their owners; logos via logo.dev.

About and activity

Claude models, the Claude API, SDKs and the Console.

Anthropic releases

Other Anthropic products: Claude apps, Claude Code

Releases per month
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Official release-notes pages 6
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Claude Platform release notes
platform.claude.com
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Claude Agent SDK (Python) releases
github.com
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Claude Agent SDK (TS) releases
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Python SDK releases
github.com
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System prompts release notes
platform.claude.com
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TypeScript SDK releases
github.com
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