What's new in Claude

Claude API·Aug 18, 2025

We've released the Usage & Cost API, allowing administrators to programmatically monitor their…

We've added a new endpoint to the Admin API for retrieving organization information.

Claude API·Aug 13, 2025

We announced the deprecation of the Claude Sonnet 3.5 models

These models will be retired on October 28, 2025. We recommend migrating to Claude Sonnet 4.5 (claude-sonnet-4-5-20250929) for improved performance and capabilities. Read more in Model deprecations. The 1-hour cache duration for prompt caching no longer requires a beta header.

Claude API·Aug 12, 2025

We've launched beta support for a 1M token context window in Claude Sonnet 4 on the Claude API and Amazon…

Claude API·Aug 11, 2025

Some customers might encounter 429 errors following a sharp increase in API usage due to acceleration limits…

Previously, 529 (overloaded_error) errors would occur in similar scenarios.

Claude API·Aug 8, 2025

Search result content blocks are out of beta on the Claude API and Vertex AI

This feature enables natural citations for RAG applications with proper source attribution. The beta header search-results-2025-06-09 is no longer required. Learn more in Search results.

Claude API·Aug 5, 2025

We've launched Claude Opus 4.1, an incremental update to Claude Opus 4 with enhanced capabilities and…

Claude API·Jul 28, 2025

We've released text_editor_20250728, an updated text editor tool that fixes some issues from the previous…

Claude API·Jul 24, 2025

We've increased rate limits for Claude Opus 4 on the Claude API to give you more capacity to build and scale…

For customers with usage tier 1-4 rate limits, these changes apply immediately to your account - no action needed.

Claude API·Jul 21, 2025

We've retired the Claude 2.0, Claude 2.1, and Claude Sonnet 3 models

All requests to these models will now return an error. Read more in Model deprecations.

Claude API·Jul 17, 2025

We've increased rate limits for Claude Sonnet 4 on the Claude API to give you more capacity to build and…

For customers with usage tier 1-4 rate limits, these changes apply immediately to your account - no action needed.

Claude API·Jul 3, 2025

We've launched search result content blocks in beta, enabling natural citations for RAG applications

Tools can now return search results with proper source attribution, and Claude will automatically cite these sources in its responses - matching the citation quality of web search. This eliminates the need for document workarounds in custom knowledge base applications. Learn more in Search results. To enable this feature, use the beta header search-results-2025-06-09.

Claude API·Jun 30, 2025

We announced the deprecation of the Claude Opus 3 model

Read more in Model deprecations.

Claude API·Jun 23, 2025

Console users with the Developer role can now access the Cost page

Previously, the Developer role allowed access to the Usage page, but not the Cost page.

Claude API·Jun 11, 2025

We've launched fine-grained tool streaming in public beta, a feature that enables Claude to stream tool use…

To enable fine-grained tool streaming, use the beta header fine-grained-tool-streaming-2025-05-14.

Claude API·May 22, 2025

We've launched Claude Opus 4 and Claude Sonnet 4, our latest models with extended thinking capabilities

Learn more in Models overview. The default behavior of extended thinking in Claude 4 models returns a summary of Claude's full thinking process, with the full thinking encrypted and returned in the signature field of thinking block output. We've launched interleaved thinking in public beta, a feature that enables Claude to think in between tool calls. We've launched the Files API in public beta, enabling you to upload files and reference them in the Messages API and code execution tool. We've launched the Code execution tool in public beta, a tool that enables Claude to execute Python code in a secure, sandboxed environment. We've launched the MCP connector in public beta, a feature that allows you to connect to remote MCP servers directly from the Messages API. To increase answer quality and decrease tool errors, we've changed the default value for the top_p nucleus sampling parameter in the Messages API from 0.999 to 0.99 for all models. Our Go SDK has moved from beta to its first stable release. We've included minute and hour level granularity to the Usage page of Console alongside 429 error rates on the Usage page.

Claude API·May 21, 2025

Our Ruby SDK has moved from beta to its first stable release

Claude API·May 7, 2025

We've launched a web search tool in the API, allowing Claude to access up-to-date information from the web

Learn more in Web search tool.

Claude API·May 1, 2025

Cache control must now be specified directly in the parent content block of tool_result and document.source

For backwards compatibility, if cache control is detected on the last block in tool_result.content or document.source.content, it will be automatically applied to the parent block instead. Cache control on any other blocks within tool_result.content and document.source.content will result in a validation error.

Claude API·Apr 9, 2025

We launched a beta version of the Ruby SDK

Claude API·Mar 31, 2025

Our Java SDK has moved from beta to its first stable release

We've moved our Go SDK from alpha to beta.

Claude API·Feb 27, 2025

We've added URL source blocks for images and PDFs in the Messages API

You can now reference images and PDFs directly through a URL instead of having to base64-encode them. Learn more in Vision and PDF support. We've added support for a none option to the tool_choice parameter in the Messages API that prevents Claude from calling any tools. We've launched an OpenAI-compatible API endpoint, allowing you to test Claude models by changing just your API key, base URL, and model name in existing OpenAI integrations.

Claude API·Feb 24, 2025

We've launched Claude Sonnet 3.7, our most intelligent model yet

Claude Sonnet 3.7 can produce near-instant responses or show its extended thinking step-by-step. One model, two ways to think. Learn more about all Claude models in Models overview. We've added vision support to Claude Haiku 3.5, enabling the model to analyze and understand images. We've released a token-efficient tool use implementation, improving overall performance when using tools with Claude. We've changed the default temperature in the Console for new prompts from 0 to 1 for consistency with the default temperature in the API. We've released updated versions of our tools that decouple the text edit and bash tools from the computer use system prompt: * bash_20250124: Same functionality as previous version but is independent from computer use.

Claude API·Feb 10, 2025

We've added the anthropic-organization-id response header to all API responses

This header provides the organization ID associated with the API key used in the request.

Claude API·Jan 31, 2025

We've moved our Java SDK from alpha to beta

Claude API·Jan 23, 2025

We've launched citations capability in the API, allowing Claude to provide source attribution for information

Learn more in Citations. We've added support for plain text documents and custom content documents in the Messages API.

Claude API·Jan 21, 2025

We announced the deprecation of the Claude 2, Claude 2.1, and Claude Sonnet 3 models

Read more in Model deprecations.

Claude API·Jan 15, 2025

We've updated prompt caching to be easier to use

Now, when you set a cache breakpoint, we'll automatically read from your longest previously cached prefix. You can now put words in Claude's mouth when using tools.

Claude API·Jan 10, 2025

We've optimized support for prompt caching in the Message Batches API to improve cache hit rate

Claude API·Dec 19, 2024

We've added support for a delete endpoint in the Message Batches API