We've launched Claude Opus 5 ( claude-opus-5 ), a step-change improvement over Claude Opus 4.8. Claude Opus 5 supports a 1M token context window (both the default and the maximum), 128k max output tok…
Added
Launched Claude Opus 5 with 1M token context window support
Changed
Claude Opus 5 provides improved capabilities over Claude Opus 4.8
You can now set an effort level on a Claude Managed Agents agent's model configuration. Pass effort inside the model object when you create the agent . See Effort levels for what each level does. Webh…
Added
Set an effort level on a Claude Managed Agents agent's model configuration by passing effort inside the model object when creating the agent
The legacy Workbench ( platform.claude.com/workbench ) in the Claude Console is being sunset with access ending on August 17, 2026. Saved prompts, variables, and evals are not supported in the updated…
Removed
Legacy Workbench at platform.claude.com/workbench will sunset with access ending on August 17, 2026
Mid-conversation system messages are available on Claude Fable 5, Claude Mythos 5, and Claude Opus 4.8, on the Claude API, Claude in Amazon Bedrock , and Google Cloud . No beta header is required. Thi…
Added
Mid-conversation system messages are now available on Claude Fable 5, Claude Mythos 5, and Claude Opus 4.8 via the Claude API, Claude in Amazon Bedrock, and Google Cloud
You can now manage the people in your Claude Enterprise (claude.ai) organization with the Admin API , in beta for all Claude Enterprise organizations: list members and look them up by email address, c…
Added
Admin API in beta for Claude Enterprise organizations to manage people in your organization, including the ability to list members and look them up by email address
Dreams (research preview) now supports Claude Fable 5 and Claude Sonnet 5. See Supported models . We've expanded the Access Transparency documentation of cmek_preserve events with a filter example, an…
Added
Dreams (research preview) now supports Claude Fable 5 and Claude Sonnet 5
You can now set an expiration when you create an API key or an Admin API key in the Claude Console . Choose a preset, a custom duration, or Never . For keys with a lifetime of at least 7 days, Anthrop…
Added
Set an expiration when creating an API key or Admin API key in the Claude Console with preset, custom duration, or never-expiring options
We've added the agent-memory-2026-07-22 beta header, which changes how listing memories ( GET /v1/memory_stores/{memory_store_id}/memories ) behaves: results are returned in a stable, server-defined o…
Added
Added agent-memory-2026-07-22 beta header for controlling memory listing behavior
Changed
Memory listing endpoint (GET /v1/memory_stores/{memory_store_id}/memories) now returns results in stable, server-defined order when using the agent-memory-2026-07-22 header
We've launched Claude Sonnet 5 ( claude-sonnet-5 ), the next generation of our Sonnet model family, at introductory pricing of $2 / $10 per MTok through August 31, 2026 (standard $3 / $15 thereafter).…
Added
Launched Claude Sonnet 5 model with model ID claude-sonnet-5
We've removed fast mode for Claude Opus 4.6. Requests to claude-opus-4-6 with speed: "fast" no longer run at fast speed or premium pricing: they run at standard speed, are billed at standard rates, an…
Removed
Fast mode for Claude Opus 4.6 has been removed, and requests with speed set to 'fast' now run at standard speed and are billed at standard rates instead
We've raised rate limits across the Claude API. Claude Sonnet and Claude Haiku rate limits now match Claude Opus at every usage tier, and usage tiers have been consolidated into three: Start, Build, a…
Changed
Rate limits have been raised across the Claude API, with Claude Sonnet and Claude Haiku rate limits now matching Claude Opus at every usage tier
Usage tiers have been consolidated into three tiers: Start, Build, and Scale
We've deprecated fast mode for Claude Opus 4.7, with removal on July 24, 2026. After removal, requests to claude-opus-4-7 with speed: "fast" will return an error. Migrate to fast mode for Claude Opus…
Deprecated
Fast mode for Claude Opus 4.7 is deprecated, with removal on July 24, 2026
MCP tunnels (research preview): the management API moved from /v1/organizations/tunnels on the Admin API to /v1/tunnels on the Claude API. The new surface uses the anthropic-beta: mcp-tunnels-2026-06-…
Changed
MCP tunnels management API moved from /v1/organizations/tunnels on the Admin API to /v1/tunnels on the Claude API
MCP tunnels now use the anthropic-beta: mcp-tunnels-2026-06-… header
The Python, TypeScript, Go, Java, Ruby, PHP, and C# SDKs now include support for code_execution_20260120 , the code execution tool version that adds REPL state persistence and is the minimum version f…
Added
Python, TypeScript, Go, Java, Ruby, PHP, and C# SDKs now include support for code_execution_20260120 tool version with REPL state persistence