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For updates to Claude Code, see the [complete CHANGELOG.md](https://github.com/anthropics/claude-code/blob/main/CHANGELOG.md) in the `claude-code` repository. </Tip> +### August 18, 2026 + +* Workbench is now [**Playground**](https://platform.claude.com/playground) in the Claude Console. Playground supports every Messages API parameter and includes templates that demonstrate API features such as code execution and web search. It shows the full SDK request and the API response for each run, to help you understand the API and build with it. For more, see the [Claude Help Center](https://support.claude.com/en/articles/8606378-how-do-i-use-playground) or try it at [platform.claude.com/playground](https://platform.claude.com/playground). + ### August 11, 2026 * The [Compliance API](https://platform.claude.com/docs/en/manage-claude/compliance-api) now returns transcripts of Cowork and Claude Code sessions that run on your users' machines, in beta for Claude Enterprise organizations. `GET /v1/compliance/apps/sessions/local` lists sessions across your organization, `GET /v1/compliance/apps/sessions/local/{session_id}` retrieves one session's metadata, and `GET /v1/compliance/apps/sessions/local/{session_id}/messages` returns its transcript, all with your existing Compliance Access Key and the `read:compliance_user_data` scope. See [Sessions on users' machines](https://platform.claude.com/docs/en/manage-claude/compliance-sessions#retrieve-local-sessions).
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The first capture of this source. The page was already there, and this is what it said.
---
title: Claude Platform release notes
url: https://platform.claude.com/docs/en/release-notes/overview
description: Updates to the Claude Platform, including the Claude API, client SDKs, and the Claude Console.
---
<Tip>
For release notes on Claude Apps, see the [Release notes for Claude Apps in the Claude Help Center](https://support.claude.com/en/articles/12138966-release-notes).
For updates to Claude Code, see the [complete CHANGELOG.md](https://github.com/anthropics/claude-code/blob/main/CHANGELOG.md) in the `claude-code` repository.
</Tip>
### August 11, 2026
* The [Compliance API](https://platform.claude.com/docs/en/manage-claude/compliance-api) now returns transcripts of Cowork and Claude Code sessions that run on your users' machines, in beta for Claude Enterprise organizations. `GET /v1/compliance/apps/sessions/local` lists sessions across your organization, `GET /v1/compliance/apps/sessions/local/{session_id}` retrieves one session's metadata, and `GET /v1/compliance/apps/sessions/local/{session_id}/messages` returns its transcript, all with your existing Compliance Access Key and the `read:compliance_user_data` scope. See [Sessions on users' machines](https://platform.claude.com/docs/en/manage-claude/compliance-sessions#retrieve-local-sessions).
* We've added the `anthropic-workspace-id` response header to the Claude API. It carries the `wrkspc_`-prefixed ID of the workspace that the request's API key or access token resolved to, including your organization's Default Workspace. See [Identify the workspace behind an API response](https://platform.claude.com/docs/en/manage-claude/workspaces#identify-the-workspace-behind-an-api-response).
### August 10, 2026
* The introductory pricing for **Claude Sonnet 5** ($2 / $10 per MTok) is now the standard price: the previously scheduled increase to $3 / $15 per MTok on September 1, 2026 will not occur. See [Pricing](https://platform.claude.com/docs/en/about-claude/pricing).
### August 7, 2026
* You can now set a budget on a Claude Managed Agents session: a hard cap on the session's spend, priced at public list rates. A session that reaches its budget pauses with the `budget_reached` stop reason instead of starting new model requests; changing or removing the budget resumes it. Deployments accept the same budget and apply it to each session they start. See [Session budgets](https://platform.claude.com/docs/en/managed-agents/budgets).
* You can now give a Claude Managed Agents session an advisor: a model at least as capable as the agent's own that the session's primary thread can consult mid-turn for strategic guidance. Configure it as a `{"type": "advisor"}` entry in the agent's multiagent roster, naming the `model` to consult. See [Give the session an advisor](https://platform.claude.com/docs/en/managed-agents/multiagent-orchestration#give-the-session-an-advisor).
* You can now control where model inference runs for a Claude Managed Agents agent. Set `inference_geo` inside the `model` object when you [create the agent](https://platform.claude.com/docs/en/managed-agents/agent-setup#pin-the-inference-geo), or [override it for a single session](https://platform.claude.com/docs/en/managed-agents/sessions#pin-the-inference-geo-for-a-session). See [Data residency](https://platform.claude.com/docs/en/manage-claude/data-residency) for the available geos and pricing.
* Claude Managed Agents sessions can now [load skills from a GitHub repository](https://platform.claude.com/docs/en/managed-agents/skills#load-skills-from-a-github-repository). When a session [mounts a repository](https://platform.claude.com/docs/en/managed-agents/github), any skills in its root `.claude/skills` directory are discovered automatically at session start and available to the agent for that session.
### August 5, 2026
* **Inference hooks** are now in beta for Claude Enterprise organizations. Point Claude at your organization's AI security server, and each governed prompt across claude.ai, Cowork, and Claude Code is held for the server's allow or deny verdict before inference proceeds. Requests are signed, failure handling is configurable, and every denial is recorded in the compliance [Activity Feed](https://platform.claude.com/docs/en/manage-claude/compliance-activity-feed). See [Inference hooks](https://platform.claude.com/docs/en/manage-claude/inference-hooks).
* We've retired the Claude Opus 4.1 model (`claude-opus-4-1-20250805`). All requests to this model on the Claude API will now return an error. We recommend upgrading to [Claude Opus 5](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison). Researchers can request ongoing access through the [External Researcher Access Program](https://support.claude.com/en/articles/9125743-what-is-the-external-researcher-access-program).
### August 3, 2026
* The [Compliance API](https://platform.claude.com/docs/en/manage-claude/compliance-api) now returns transcripts of Cowork sessions started on claude.ai web or mobile, in beta for Claude Enterprise organizations. `GET /v1/compliance/apps/sessions/remote` lists sessions and `GET /v1/compliance/apps/sessions/remote/{session_id}/messages` returns one session's transcript, using your existing Compliance Access Key with the `read:compliance_user_data` scope. See [Sessions in the cloud](https://platform.claude.com/docs/en/manage-claude/compliance-sessions#retrieve-remote-sessions).
### August 1, 2026
* [Dreams](https://platform.claude.com/docs/en/managed-agents/dreams) (research preview) now supports Claude Opus 5. See [Supported models](https://platform.claude.com/docs/en/managed-agents/dreams#limits).
### July 24, 2026
* 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](https://platform.claude.com/docs/en/build-with-claude/context-windows) (both the default and the maximum), 128k max output tokens, and [thinking](https://platform.claude.com/docs/en/build-with-claude/thinking) on by default, at $5 / $25 USD per MTok, the same pricing as Claude Opus 4.8. It's available on the Claude API, [Claude in Amazon Bedrock](https://platform.claude.com/docs/en/build-with-claude/claude-in-amazon-bedrock), [Claude on Google Cloud](https://platform.claude.com/docs/en/build-with-claude/claude-on-vertex-ai), and [Claude in Microsoft Foundry](https://platform.claude.com/docs/en/build-with-claude/claude-in-microsoft-foundry). See [What's new in Claude Opus 5](https://platform.claude.com/docs/en/about-claude/models/whats-new-opus-5) for new features, behavior changes, and migration guidance, and the [models overview](https://platform.claude.com/docs/en/about-claude/models/overview) for complete specs.
* On Claude Opus 5, disabling thinking is allowed only at effort `high` or below: `thinking: {"type": "disabled"}` with effort `xhigh` or `max` returns a 400 error, a breaking change from Claude Opus 4.8. See [What's new in Claude Opus 5](https://platform.claude.com/docs/en/about-claude/models/whats-new-opus-5#behavior-changes).
* [Effort](https://platform.claude.com/docs/en/build-with-claude/effort) is the primary control for steering Claude Opus 5: the model supports the full ladder (`low`, `medium`, `high`, `xhigh`, `max`), with `max` for capability-critical work.
* Mid-conversation tool changes are now in beta on Claude Fable 5, Claude Mythos 5, Claude Opus 4.8, and Claude Opus 5: add or remove tools between turns of a conversation while preserving the prompt cache. Include the `mid-conversation-tool-changes-2026-07-01` beta header in your requests.
* The `fallbacks` parameter now supports a `"default"` mode, which applies Anthropic's recommended fallback models by refusal category. Server-side fallback is in beta, and the `"default"` mode requires the `server-side-fallback-2026-07-01` beta header. See [Refusals and fallback](https://platform.claude.com/docs/en/build-with-claude/refusals-and-fallback).
* We've removed [fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode) for Claude Opus 4.7. Requests to `claude-opus-4-7` with `speed: "fast"` now return an error; unlike Claude Opus 4.6, they do not fall back to standard speed. Claude Opus 4.7 itself remains available at standard speed. To continue using fast mode, migrate to [Claude Opus 5](https://platform.claude.com/docs/en/about-claude/models/migration-guide#migrating-from-claude-opus-47) or Claude Opus 4.8. Read more in [Fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode#supported-models).
### July 22, 2026
* 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](https://platform.claude.com/docs/en/managed-agents/agent-setup#create-an-agent). See [Effort levels](https://platform.claude.com/docs/en/build-with-claude/effort#effort-levels) for what each level does.
* Webhooks for Claude Managed Agents now cover the environment and memory store lifecycle: four `environment.*` event types and three `memory_store.*` event types. You can react to environment and memory store lifecycle changes without polling. See the Environment events and Memory store events tabs in [Subscribe to webhooks](https://platform.claude.com/docs/en/managed-agents/webhooks#supported-event-types).
* When creating a Claude Managed Agents session, you can now [seed it with initial events](https://platform.claude.com/docs/en/managed-agents/sessions#seed-the-session-with-initial-events). Pass `initial_events` on `POST /v1/sessions` with up to 50 `user.message` and `user.define_outcome` events. A non-empty list starts the agent loop in the same call, so you don't need a separate send-events request to start work.
* The `version` field is now optional when [updating a Claude Managed Agents agent](https://platform.claude.com/docs/en/managed-agents/agent-setup#update-an-agent). Supply it for optimistic concurrency (a mismatch returns a 409 error), or omit it to apply the update unconditionally. See [Update semantics](https://platform.claude.com/docs/en/managed-agents/agent-setup#update-semantics).
* Claude Managed Agents session thread event streams now support [event deltas](https://platform.claude.com/docs/en/managed-agents/events-and-streaming#event-deltas). `GET /v1/sessions/{session_id}/threads/{thread_id}/stream` accepts the same `event_deltas[]` query parameter as the session-level stream, so you can preview a subagent's text as the model generates it. A connection previews only the thread it's reading. See [Preview session thread events](https://platform.claude.com/docs/en/managed-agents/events-and-streaming#preview-session-thread-events).
### July 17, 2026
* The legacy **Workbench** ([platform.claude.com/workbench](https://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 [Workbench](https://platform.claude.com/playground). You can export any data you want to keep from the banner and under your **Organizational Settings**. For more, see [How do I use the Workbench?](https://support.claude.com/en/articles/8606378-how-do-i-use-the-workbench) in the Claude Help Center.
* The experimental prompt tools APIs for generating, improving, and templatizing prompts (`/v1/experimental/generate_prompt`, `/v1/experimental/improve_prompt`, and `/v1/experimental/templatize_prompt`) are being retired along with the Workbench on August 17, 2026. After removal, requests to these endpoints will return an error.
### July 15, 2026
* [Mid-conversation system messages](https://platform.claude.com/docs/en/build-with-claude/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](https://platform.claude.com/docs/en/build-with-claude/claude-in-amazon-bedrock), and [Google Cloud](https://platform.claude.com/docs/en/build-with-claude/claude-on-vertex-ai). No beta header is required. This corrects earlier availability notes.
### July 14, 2026
* You can now manage the people in your **Claude Enterprise** (claude.ai) organization with the [Admin API](https://platform.claude.com/docs/en/api/admin), in beta for all Claude Enterprise organizations: list members and look them up by email address, change a member's role, remove members, send and withdraw invites, manage groups and their membership, and read custom roles. Group and custom-role requests require the `anthropic-beta: ce-user-management-2026-07-13` beta header; member and invite requests take no beta header. An Admin API key with the `read:org_audit` scope can also call every user-management `GET` endpoint. See [User management](https://platform.claude.com/docs/en/manage-claude/user-management).
### July 10, 2026
* [Dreams](https://platform.claude.com/docs/en/managed-agents/dreams) (research preview) now supports Claude Fable 5 and Claude Sonnet 5. See [Supported models](https://platform.claude.com/docs/en/managed-agents/dreams#limits).
* We've expanded the [Access Transparency](https://platform.claude.com/docs/en/manage-claude/access-transparency) documentation of `cmek_preserve` events with a filter example, an example event payload, and two preservation reason codes (`policy_violation_investigation`, `csae_report`). The documentation now also clarifies that a preservation event is written whether the preservation was initiated by a human reviewer or an automated safety pipeline. See [CMEK content preservation](https://platform.claude.com/docs/en/manage-claude/access-transparency#cmek-content-preservation).
### July 8, 2026
* You can now set an expiration when you create an API key or an Admin API key in the [Claude Console](https://platform.claude.com/settings/keys). Choose a preset, a custom duration, or **Never**. For keys with a lifetime of at least 7 days, Anthropic emails the creator before expiration. Existing keys are unaffected. The Admin API reports each key's expiration in the [`expires_at`](https://platform.claude.com/docs/en/api/admin/api_keys/list) field. See [Authentication](https://platform.claude.com/docs/en/manage-claude/authentication#key-expiration).
### July 2, 2026
* We've added the `agent-memory-2026-07-22` beta header, which changes how [listing memories](https://platform.claude.com/docs/en/managed-agents/memory#list-memories) (`GET /v1/memory_stores/{memory_store_id}/memories`) behaves: results are returned in a stable, server-defined order and the `order_by` and `order` parameters are ignored; `depth` accepts only `0`, `1`, or being omitted (other values return a `400` error); and `path_prefix` must end with `/` and matches whole path segments instead of a substring. Page cursors issued without the header aren't valid with it, so restart from the first page when you adopt it. On memory store endpoints, `agent-memory-2026-07-22` replaces `managed-agents-2026-04-01`; sending both returns a `400` error. On July 22, 2026, the `managed-agents-2026-04-01` header adopts the same list behavior. See [Beta headers](https://platform.claude.com/docs/en/api/beta-headers#endpoint-specific-headers).
* The Python (0.116.0), TypeScript (0.110.0), Go (1.56.0), Java (2.48.0), Ruby (1.55.0), PHP (0.36.0), C# (12.35.0), and CLI (1.16.0) SDKs now send `agent-memory-2026-07-22` on all memory store calls instead of `managed-agents-2026-04-01`. If your code passes `betas` explicitly on memory store calls, replace `managed-agents-2026-04-01` with `agent-memory-2026-07-22` there rather than adding a second value.
### July 1, 2026
* We've restored access to Claude Fable 5 and Claude Mythos 5. See [our statement](https://www.anthropic.com/news/redeploying-fable-5) for more information.
### June 30, 2026
* 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 (made the standard price on August 10, 2026). Claude Sonnet 5 supports a [1M token context window](https://platform.claude.com/docs/en/build-with-claude/context-windows), 128k max output tokens, and the same set of tools and platform features as Claude Sonnet 4.6, except [Priority Tier](https://platform.claude.com/docs/en/api/service-tiers#supported-models), which is not available on Claude Sonnet 5. Three behavior changes apply when migrating: [adaptive thinking](https://platform.claude.com/docs/en/build-with-claude/thinking) is now on by default; manual extended thinking (`thinking: {type: "enabled", budget_tokens: N}`) is removed and returns a 400 error (it was deprecated on Sonnet 4.6); and setting sampling parameters (`temperature`, `top_p`, `top_k`) to non-default values returns a 400 error. Claude Sonnet 5 also uses a new tokenizer that produces approximately 30% more tokens for the same text. The exact increase depends on the content and workload shape. See [What's new in Claude Sonnet 5](https://platform.claude.com/docs/en/about-claude/models/whats-new-sonnet-5) for details and migration guidance. For behavioral differences and model-specific prompting patterns, see [Prompting Claude Sonnet 5](https://platform.claude.com/docs/en/build-with-claude/prompt-engineering/prompting-claude-sonnet-5).
* Claude Managed Agents session event streams now support [event deltas](https://platform.claude.com/docs/en/managed-agents/events-and-streaming#event-deltas). Opt in with the `event_deltas[]` query parameter on `GET /v1/sessions/{session_id}/events/stream`. The `event_start` and `event_delta` events preview an agent message's text as it's generated, before the complete `agent.message` event arrives.
* [Listing sessions](https://platform.claude.com/docs/en/managed-agents/session-operations#listing-sessions) for Claude Managed Agents now supports backward pagination. `GET /v1/sessions` returns a `prev_page` cursor alongside `next_page`; pass it as the `page` parameter to return to the previous page. See [Pagination](https://platform.claude.com/docs/en/api/overview#pagination).
* When creating a Claude Managed Agents session, you can now [override the agent's configuration for that session](https://platform.claude.com/docs/en/managed-agents/sessions#override-agent-configuration-for-a-session). Pass `agent` with `type: "agent_with_overrides"` to replace the model, system prompt, tools, MCP servers, or skills for a single session. The agent itself is unchanged.
* Claude Managed Agents vaults now support an `injection_location` setting on [environment variable credentials](https://platform.claude.com/docs/en/managed-agents/vaults#add-a-credential) (the Environment variable tab). It controls whether the credential's value is substituted, at egress, into the agent's outbound request headers, the request body, or both.
* Webhooks for Claude Managed Agents now cover the agent, deployment, and deployment run lifecycle. You can react to a newly published agent version, a paused deployment, or a failed scheduled run without polling. See the Agent events, Deployment events, and Deployment run events tabs in [Subscribe to webhooks](https://platform.claude.com/docs/en/managed-agents/webhooks#supported-event-types).
### June 29, 2026
* We've removed [fast mode](https://platform.claude.com/docs/en/build-with-claude/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, and do not return an error. The response's `usage.speed` field reports the speed used. To continue using fast mode, migrate to [Claude Opus 4.8](https://platform.claude.com/docs/en/about-claude/models/migration-guide). Read more in [Fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode#supported-models).
### June 26, 2026
* We've raised [rate limits](https://platform.claude.com/docs/en/api/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, and Scale. Most organizations move to a higher tier, no organization receives lower limits than before, and no action is required. You can view your tier and current limits in the [Claude Console](https://platform.claude.com/settings/limits).
### June 25, 2026
* We've deprecated [fast mode](https://platform.claude.com/docs/en/build-with-claude/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 4.8. Read more in [Fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode#supported-models).
### June 22, 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-2026-06-22` header and the `workspace:manage_tunnels` WIF scope. The previous surface remains available during a migration window. See the [Tunnels API reference](https://platform.claude.com/docs/en/api/beta/tunnels).
### June 18, 2026
* The Python, TypeScript, Go, Java, Ruby, PHP, and C# SDKs now include support for `code_execution_20260120`, the [code execution tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool) version that adds REPL state persistence and is the minimum version for [programmatic tool calling](https://platform.claude.com/docs/en/agents-and-tools/tool-use/programmatic-tool-calling). To adopt it, set the tool's `type` to `code_execution_20260120`; no beta header is required. It's available on Claude Fable 5, Claude Mythos 5, Claude Opus 4.5 and newer, and Claude Sonnet 4.5 and newer; see the [model compatibility table](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool#model-compatibility).
### June 15, 2026
* We've retired the Claude Sonnet 4 model (`claude-sonnet-4-20250514`) and the Claude Opus 4 model (`claude-opus-4-20250514`). All requests to these models on the Claude API will now return an error. We recommend upgrading to [Claude Sonnet 4.6](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison) and [Claude Opus 4.8](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison) respectively. Researchers can request ongoing access through the [External Researcher Access Program](https://support.claude.com/en/articles/9125743-what-is-the-external-researcher-access-program).
### June 11, 2026
* The [code execution tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool) now supports `code_execution_20260521`, which discloses the 90-second per-cell execution time limit in the tool description so Claude can budget long-running cells. No beta header is required.
* The [web search tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/web-search-tool) and [web fetch tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/web-fetch-tool) now support `web_search_20260318` and `web_fetch_20260318`, adding a `response_inclusion` parameter to drop consumed result blocks from the API response for agentic workflows. No beta header is required.
### June 10, 2026
* The `GET /v1/environments/{id}/work` endpoint, which lists pending work for a [self-hosted sandbox](https://platform.claude.com/docs/en/managed-agents/self-hosted-sandboxes), is now available on [Claude Platform on AWS](https://platform.claude.com/docs/en/build-with-claude/claude-platform-on-aws). See [IAM actions for Claude Platform on AWS](https://platform.claude.com/docs/en/api/claude-platform-on-aws-iam-actions) for the `GetEnvironment` action that authorizes it.
### June 9, 2026
* We've launched **Claude Fable 5** (`claude-fable-5`), our most capable widely released model, alongside **Claude Mythos 5** (`claude-mythos-5`) for Project Glasswing participants. Both models support a [1M token context window](https://platform.claude.com/docs/en/build-with-claude/context-windows) by default, 128k max output tokens, and always-on [adaptive thinking](https://platform.claude.com/docs/en/build-with-claude/thinking). See [Introducing Claude Fable 5 and Claude Mythos 5](https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5) for capabilities, API changes, and availability.
* Claude Fable 5 and Claude Mythos 5 use the tokenizer introduced with Claude Opus 4.7. Compared to models before Claude Opus 4.7, the same text produces roughly 30% more tokens. The exact increase depends on the content and workload shape. Use the [token counting API](https://platform.claude.com/docs/en/build-with-claude/token-counting#token-counts-on-claude-fable-5) with `model: "claude-fable-5"` to measure your prompts under the new tokenizer.
* Claude Fable 5 runs safety classifiers on requests and during response generation. When a classifier declines a request, the Messages API returns `stop_reason: "refusal"`. You are not billed for a request refused before any output is generated. An opt-in `fallbacks` parameter (in beta on the Claude API and Claude Platform on AWS; not supported on the Message Batches API) re-runs refused requests on another model, billed at the fallback model's rates. See [Handling stop reasons](https://platform.claude.com/docs/en/build-with-claude/handling-stop-reasons).
* The [`stop_details.category`](https://platform.claude.com/docs/en/build-with-claude/refusals-and-fallback#refusal-response) field on refusal responses now includes `"reasoning_extraction"` on Claude Fable 5, returned when a request is blocked under Anthropic's Terms of Service restrictions on reverse engineering or duplicating model outputs. The existing `"cyber"` and `"bio"` categories are unchanged. No beta header is required.
* On Claude Fable 5 and Claude Mythos 5, [adaptive thinking](https://platform.claude.com/docs/en/build-with-claude/thinking) is the only thinking mode: `thinking: {"type": "disabled"}` is not supported, and manual extended thinking budgets and assistant prefill are not supported (both return a 400 error). See [Migrating from Claude Mythos Preview to Claude Mythos 5](https://platform.claude.com/docs/en/about-claude/models/migration-guide#migrating-from-claude-mythos-preview).
* On Claude Fable 5 and Claude Mythos 5, `thinking.display` defaults to `"omitted"`, the same as Claude Opus 4.8, Claude Opus 4.7, and Claude Mythos Preview; set `display: "summarized"` to receive readable thinking summaries. The raw chain of thought is never returned; pass thinking blocks back unchanged in multi-turn conversations on the same model. See [Thinking output on Claude Fable 5 and Claude Mythos 5](https://platform.claude.com/docs/en/build-with-claude/thinking#thinking-output-on-claude-fable-5-and-claude-mythos-5).
* Claude Fable 5 requires 30-day data retention and is not available under zero data retention. See [Model-specific data retention requirements](https://platform.claude.com/docs/en/manage-claude/api-and-data-retention#model-specific-data-retention-requirements).
* Claude Managed Agents now supports [scheduled deployments](https://platform.claude.com/docs/en/managed-agents/scheduled-deployments), letting you run sessions on a cron schedule without managing your own scheduler.
* Claude Managed Agents vaults now support [environment variable credentials](https://platform.claude.com/docs/en/managed-agents/vaults#add-a-credential), so you can securely inject secrets into the agent's sandbox for CLIs, SDKs, and other services that authenticate through environment variables.
* The [Compliance API](https://platform.claude.com/docs/en/manage-claude/compliance-api) [Activity Feed](https://platform.claude.com/docs/en/manage-claude/compliance-activity-feed) (`GET /v1/compliance/activities`) is now available on [Claude Platform on AWS](https://platform.claude.com/docs/en/build-with-claude/claude-platform-on-aws). See [IAM actions for Claude Platform on AWS](https://platform.claude.com/docs/en/api/claude-platform-on-aws-iam-actions#compliance) for the `ListComplianceActivities` action that authorizes it.
* The `session.thread_*` webhook events now include a `session_thread_id` field identifying the multiagent thread that triggered the event.
* We've released a [Swift package](https://platform.claude.com/docs/en/cli-sdks-libraries/libraries/apple-foundation-models) in beta that adds Claude as a server-side `LanguageModel` in Apple's Foundation Models framework. Call Claude through the same `LanguageModelSession` API as Apple's on-device model on iOS 27, macOS 27, visionOS 27, and watchOS 27 (beta).
### June 5, 2026
* We announced the deprecation of the Claude Opus 4.1 model (`claude-opus-4-1-20250805`), with retirement on the Claude API scheduled for August 5, 2026. We recommend migrating to [Claude Opus 4.8](https://platform.claude.com/docs/en/about-claude/models/migration-guide). Read more in [Model deprecations](https://platform.claude.com/docs/en/about-claude/model-deprecations).
### June 2, 2026
* The [advisor tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/advisor-tool) now supports a `max_tokens` parameter to cap the advisor model's output per call, reducing latency and output token cost for workloads that don't need full-length advisor responses. Set `tools[].max_tokens` on the advisor tool definition; see [Capping advisor output](https://platform.claude.com/docs/en/agents-and-tools/tool-use/advisor-tool#capping-advisor-output).
* On the Claude API, you are no longer billed for a request when it returns `stop_reason: "refusal"` without Claude having generated any output. See [Streaming refusals](https://platform.claude.com/docs/en/test-and-evaluate/strengthen-guardrails/handle-streaming-refusals) for detecting and handling refusals.
### May 29, 2026
* Claude Managed Agents [webhooks](https://platform.claude.com/docs/en/managed-agents/webhooks), [multiagent orchestration](https://platform.claude.com/docs/en/managed-agents/multiagent-orchestration), and [self-hosted sandboxes](https://platform.claude.com/docs/en/managed-agents/self-hosted-sandboxes) are now available on [Claude Platform on AWS](https://platform.claude.com/docs/en/build-with-claude/claude-platform-on-aws). See [IAM actions for Claude Platform on AWS](https://platform.claude.com/docs/en/api/claude-platform-on-aws-iam-actions) for the new IAM actions and the `AnthropicSelfHostedEnvironmentAccess` managed policy.
### May 28, 2026
* We've launched **Claude Opus 4.8** (claude-opus-4-8), our most capable generally available model. Claude Opus 4.8 supports a [1M token context window](https://platform.claude.com/docs/en/build-with-claude/context-windows) by default on the Claude API, Amazon Bedrock, Google Cloud, and Microsoft Foundry, 128k max output tokens, and the same set of tools and platform features as Claude Opus 4.7. See the [migration guide](https://platform.claude.com/docs/en/about-claude/models/migration-guide) for baseline settings, features, and migration guidance.
* We've launched [mid-conversation system messages](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages). On Claude Opus 4.8, you can send `role: "system"` messages after a user turn (subject to [placement rules](https://platform.claude.com/docs/en/build-with-claude/mid-conversation-system-messages#limitations)) in the `messages` array, preserving prompt cache hits when instructions change during a long-running session. No beta header is required.
* The [`stop_details`](https://platform.claude.com/docs/en/build-with-claude/refusals-and-fallback#refusal-response) field on refusal responses is now publicly documented; it returns a `category` (`cyber`, `bio`, or `null`) and a human-readable `explanation`, so your application can route different classes of refusal to the right next step. No beta header is required.
* On Claude Opus 4.8, the [effort parameter](https://platform.claude.com/docs/en/build-with-claude/effort) defaults to `high` across all surfaces, including Claude Code and the Messages API.
* On Claude Opus 4.8, the minimum cacheable prompt length for [prompt caching](https://platform.claude.com/docs/en/build-with-claude/prompt-caching) is 1,024 tokens, lower than on Claude Opus 4.7.
* With [adaptive thinking](https://platform.claude.com/docs/en/build-with-claude/thinking) enabled, Claude Opus 4.8 triggers reasoning only when a turn needs it, reducing wasted thinking tokens compared to Claude Opus 4.7 at the same effort level.
* Claude Opus 4.8 supports [high-resolution image input](https://platform.claude.com/docs/en/build-with-claude/vision#high-resolution-image-support-on-claude-opus-4-7) (up to 2576 pixels on the long edge), same as Claude Opus 4.7.
* [Task budgets](https://platform.claude.com/docs/en/build-with-claude/task-budgets) now support Claude Opus 4.8.
* The [advisor tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/advisor-tool) now supports Claude Opus 4.8.
* [Computer use](https://platform.claude.com/docs/en/agents-and-tools/tool-use/computer-use-tool) now supports Claude Opus 4.8.
* [Fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode) for Claude Opus 4.8 is available as a research preview on the Claude API only.
* Setting the sampling parameters `temperature`, `top_p`, or `top_k` to a non-default value returns a 400 error on Claude Opus 4.8, same as on Claude Opus 4.7. See the [migration guide](https://platform.claude.com/docs/en/about-claude/models/migration-guide) for details.
* In Claude Code, we've expanded Auto mode to more users for long-running tasks. See the [Claude Code documentation](https://code.claude.com/docs).
* In Claude Code, Max plan users now default to [fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode) on Claude Opus 4.8. See the [Claude Code documentation](https://code.claude.com/docs).
* In Claude Code, Workflows are available as a research preview, letting you define and run multistep agentic plans. See the [Claude Code documentation](https://code.claude.com/docs).
* We've deprecated [fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode) for Claude Opus 4.6, with removal approximately 30 days after launch. Migrate to fast mode for Claude Opus 4.8 or Claude Opus 4.7. Read more in [Fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode#supported-models).
* For updates to claude.ai, Cowork, Claude for Microsoft 365, and other Claude apps in this release, see the [release notes for Claude Apps](https://support.claude.com/en/articles/12138966-release-notes).
### May 27, 2026
* The Messages API response now includes [`usage.output_tokens_details.thinking_tokens`](https://platform.claude.com/docs/en/build-with-claude/extended-thinking#budget-rules-and-tuning), reporting how many of the billed output tokens were extended thinking. When streaming, the breakdown appears only on the final `message_delta` event. No beta header is required.
### May 19, 2026
* [MCP tunnels](https://platform.claude.com/docs/en/agents-and-tools/mcp-tunnels/overview) is now available as a research preview, so you can connect to MCP servers in your private network.
* Self-hosted sandboxes are now available for Claude Managed Agents, as an alternative to running tool execution in Anthropic's infrastructure. See [Self-hosted sandboxes](https://platform.claude.com/docs/en/managed-agents/self-hosted-sandboxes).
* With Claude Managed Agents, you can now update the agent's MCP server and tool configurations associated with an active session.
* With Claude Managed Agents, large outputs from `agent_toolset` and MCP tools exceeding 100K characters (about 25K tokens) are now automatically spilled to a file in the sandbox. The model receives a truncated preview with the file path and can read the full content from there.
### May 18, 2026
* The [web search tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/web-search-tool) now returns richer SEC filing data, making it easier to ground financial research agents, earnings analysis, and due-diligence workflows in primary sources with citations.
### May 13, 2026
* We've launched [cache diagnostics](https://platform.claude.com/docs/en/build-with-claude/cache-diagnostics) in public beta. Pass `diagnostics.previous_message_id` on a Messages request and the API reports a `cache_miss_reason` explaining where the prompt cache prefix diverged from the previous turn. Include the `cache-diagnosis-2026-04-07` beta header in your requests.
### May 12, 2026
* [Fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode) (research preview) now supports Claude Opus 4.7. Set `speed: "fast"` with `model: "claude-opus-4-7"` and the `fast-mode-2026-02-01` beta header for significantly faster output token generation at premium pricing. Pricing, rate limits, and access are the same as for Opus 4.6 fast mode; interested customers should join the [waitlist](https://claude.com/fast-mode).
### May 11, 2026
* We've launched **Claude Platform on AWS**, bringing the Claude API to Anthropic-managed infrastructure accessible through AWS, with AWS billing and IAM authentication. Access the full Messages API, Files API, Message Batches API, Claude Managed Agents, Agent Skills, code execution, and tool use through native AWS endpoints. Learn more in [Claude Platform on AWS](https://platform.claude.com/docs/en/build-with-claude/claude-platform-on-aws).
### May 6, 2026
* [Multiagent orchestration](https://platform.claude.com/docs/en/managed-agents/multiagent-orchestration) and [Outcomes](https://platform.claude.com/docs/en/managed-agents/define-outcomes) are now in public beta under the standard `managed-agents-2026-04-01` beta header.
* Claude Managed Agents vault credential background refresh is now supported for `mcp_oauth` credentials. See [Authenticate with vaults](https://platform.claude.com/docs/en/managed-agents/vaults).
* Webhooks for Claude Managed Agents are now supported. Webhook event types include session and vault lifecycle events. See [Subscribe to webhooks](https://platform.claude.com/docs/en/managed-agents/webhooks).
* Additional filtering and sorting options are now supported for Claude Managed Agents. Sessions can be filtered by status, and events can be filtered by type. Events can now be filtered by creation time.
* [Dreams](https://platform.claude.com/docs/en/managed-agents/dreams) for Claude Managed Agents are now available as a research preview. A dream reads an existing memory store alongside past session transcripts and produces a reorganized output memory store with duplicates merged, stale entries replaced, and new insights surfaced. Dream endpoints are gated by the `dreaming-2026-04-21` beta header. [Request access](https://claude.com/form/claude-managed-agents) to try it.
### May 4, 2026
* [Workload Identity Federation](https://platform.claude.com/docs/en/manage-claude/workload-identity-federation) is now generally available. Authenticate workloads to the Claude API with short-lived OIDC tokens from your own identity provider (AWS IAM, Google Cloud, GitHub Actions, Kubernetes, Microsoft Entra ID, Okta, SPIFFE, and more) instead of long-lived static API keys. Configure issuers and federation rules in the Claude Console, and the SDK handles token exchange and refresh automatically. See [Authentication](https://platform.claude.com/docs/en/manage-claude/authentication).
### April 30, 2026
* We've retired the 1M token context window beta (`context-1m-2025-08-07`) for Claude Sonnet 4.5 and Claude Sonnet 4. The beta header now has no effect on these models, and requests exceeding the standard 200k-token context window return an error. To use the 1M context window, migrate to [Claude Sonnet 4.6](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison) or [Claude Opus 4.6](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison), where it's generally available at standard pricing with no beta header required.
### April 29, 2026
* We've released the [Claude API skill](https://platform.claude.com/docs/en/agents-and-tools/agent-skills/claude-api-skill), an open-source [Agent Skill](https://platform.claude.com/docs/en/agents-and-tools/agent-skills/overview) that gives Claude up-to-date reference material for building on the Messages API and Claude Managed Agents across 8 languages. The skill is bundled with Claude Code and available in the [Anthropic skills repository](https://github.com/anthropics/skills/tree/main/skills/claude-api).
### April 24, 2026
* We've released the [Rate Limits API](https://platform.claude.com/docs/en/manage-claude/rate-limits-api), allowing administrators to programmatically query the rate limits configured for their organization and workspaces.
### April 23, 2026
* Memory for Claude Managed Agents is now in public beta under the standard `managed-agents-2026-04-01` header. See [Using agent memory](https://platform.claude.com/docs/en/managed-agents/memory) for the full integration guide.
### April 20, 2026
* We've retired the Claude Haiku 3 model (`claude-3-haiku-20240307`). All requests to this model will now return an error. We recommend upgrading to [Claude Haiku 4.5](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison).
### April 16, 2026
* We've launched [Claude Opus 4.7](https://www.anthropic.com/news/claude-opus-4-7), our most capable generally available model for complex reasoning and agentic coding, at the same $5 / $25 per MTok pricing as Opus 4.6. See [What's new in Claude Opus 4.7](https://platform.claude.com/docs/en/about-claude/models/whats-new-claude-4-7) for capability improvements, new features, and the updated tokenizer. Opus 4.7 includes API breaking changes versus Opus 4.6; see the [migration guide](https://platform.claude.com/docs/en/about-claude/models/migration-guide) before upgrading.
* [Claude in Amazon Bedrock](https://platform.claude.com/docs/en/build-with-claude/claude-in-amazon-bedrock) is now open to all Amazon Bedrock customers. Claude Opus 4.7 and Claude Haiku 4.5 are available self-serve from the Bedrock console through the Messages API endpoint at `/anthropic/v1/messages`, in 27 AWS regions with global and regional endpoints.
* We've launched [task budgets](https://platform.claude.com/docs/en/build-with-claude/task-budgets) in beta on Claude Opus 4.7. Give Claude an advisory token budget for a full agentic loop (thinking, tool calls, tool results, and output) and the model sees a running countdown, using it to prioritize work and finish gracefully as the budget is consumed. Include the `task-budgets-2026-03-13` beta header in your requests.
* Claude Opus 4.7 supports [high-resolution image input](https://platform.claude.com/docs/en/build-with-claude/vision#high-resolution-image-support-on-claude-opus-4-7), raising the maximum image resolution from 1568 to 2576 pixels on the long edge for improved performance on computer use, screenshot understanding, and document analysis. High-resolution support is automatic and requires no beta header; images may use up to approximately 3x more image tokens than on prior models.
* We've added the `xhigh` [effort](https://platform.claude.com/docs/en/build-with-claude/effort) level on Claude Opus 4.7. `xhigh` sits between `high` and `max` and is tuned for long-running agentic and coding tasks (over 30 minutes) with token budgets in the millions. No beta header is required.
### April 14, 2026
* We announced the deprecation of the Claude Sonnet 4 model (`claude-sonnet-4-20250514`) and the Claude Opus 4 model (`claude-opus-4-20250514`), with retirement on the Claude API scheduled for June 15, 2026. We recommend migrating to [Claude Sonnet 4.6](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison) and [Claude Opus 4.8](https://platform.claude.com/docs/en/about-claude/models/migration-guide) respectively. Read more in [Model deprecations](https://platform.claude.com/docs/en/about-claude/model-deprecations).
### April 9, 2026
* We've launched the [advisor tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/advisor-tool) in public beta. Pair a faster executor model with a higher-intelligence advisor model that provides strategic guidance mid-generation, so long-horizon agentic workloads get close to advisor-solo quality while the bulk of token generation happens at executor-model rates. Include the beta header `advisor-tool-2026-03-01` in your requests.
### April 8, 2026
* We've launched **Claude Managed Agents** in public beta, a fully managed agent harness for running Claude as an autonomous agent with secure sandboxing, built-in tools, and server-sent event streaming. Create agents, configure containers, and run sessions through the API. All endpoints require the `managed-agents-2026-04-01` beta header. Learn more in [Claude Managed Agents overview](https://platform.claude.com/docs/en/managed-agents/overview).
* We've launched the **`ant` CLI**, a command-line client for the Claude API that enables faster interaction with the Claude API, native integration with Claude Code, and versioning of API resources in YAML files. Learn more in the [CLI quickstart](https://platform.claude.com/docs/en/cli-sdks-libraries/cli/quickstart).
### April 7, 2026
* We announced [Claude Mythos Preview](https://anthropic.com/glasswing) is available as a gated research preview for defensive cybersecurity work as part of [Project Glasswing](https://anthropic.com/glasswing). Access is invitation-only.
* The [Messages API](https://platform.claude.com/docs/en/api/messages) is now available on Amazon Bedrock as a research preview. The new Claude in Amazon Bedrock endpoint at `/anthropic/v1/messages` uses the same request shape as the first-party Claude API and runs on AWS-managed infrastructure with zero operator access. Available in `us-east-1`; contact your Anthropic account executive to request access. Learn more in [Claude in Amazon Bedrock](https://platform.claude.com/docs/en/build-with-claude/claude-in-amazon-bedrock).
### March 30, 2026
* We've raised the `max_tokens` cap to 300k on the [Message Batches API](https://platform.claude.com/docs/en/build-with-claude/batch-processing#extended-output-beta) for Claude Opus 4.6 and Sonnet 4.6. Include the `output-300k-2026-03-24` beta header to generate longer single-turn outputs for long-form content, structured data, and large code generation tasks.
* We're retiring the 1M token context window beta for Claude Sonnet 4.5 and Claude Sonnet 4 on **April 30, 2026**. After that date, the `context-1m-2025-08-07` beta header will have no effect on these models, and requests that exceed the standard 200k-token context window will return an error. To continue using 1M context windows, migrate to [Claude Sonnet 4.6](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison) or [Claude Opus 4.6](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison), which support the full 1M token context window at standard pricing with no beta header required.
### March 18, 2026
* We've added model capability fields to the [Models API](https://platform.claude.com/docs/en/api/models/list). `GET /v1/models` and `GET /v1/models/{model_id}` now return `max_input_tokens`, `max_tokens`, and a `capabilities` object. Query the API to discover what each model supports.
### March 16, 2026
* We've launched the `display` field for extended thinking, letting you omit thinking content from responses for faster streaming. Set `thinking.display: "omitted"` to receive thinking blocks with an empty `thinking` field and the `signature` preserved for multi-turn continuity. Billing is unchanged. Learn more in [Controlling thinking display](https://platform.claude.com/docs/en/build-with-claude/thinking#controlling-thinking-display).
### March 13, 2026
* The [1M token context window](https://platform.claude.com/docs/en/build-with-claude/context-windows) is now generally available for Claude Opus 4.6 and Sonnet 4.6 at standard pricing. Requests over 200k tokens work automatically for these models with no beta header required. The 1M token context window remains in beta for Claude Sonnet 4.5 and Sonnet 4.
* We've removed the dedicated 1M rate limits for all supported models. Your standard account limits now apply across every context length.
* We've raised the media limit from 100 to 600 images or PDF pages per request when using the 1M token context window.
### February 19, 2026
* We've launched **automatic caching** for the Messages API. Add a single `cache_control` field to your request body and the system automatically caches the last cacheable block, moving the cache point forward as conversations grow. No manual breakpoint management required. Works alongside existing block-level cache control for fine-grained optimization. Available on the Claude API and Microsoft Foundry (preview). Learn more in [Prompt caching](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#automatic-caching).
* We've retired the Claude Sonnet 3.7 model (`claude-3-7-sonnet-20250219`) and the Claude Haiku 3.5 model (`claude-3-5-haiku-20241022`). All requests to Claude Sonnet 3.7 will now return an error. Requests to Claude Haiku 3.5 on the Claude API will now return an error; it remains available on Amazon Bedrock and Google Cloud. We recommend upgrading to [Claude Sonnet 4.6](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison) and [Claude Haiku 4.5](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison) respectively. Researchers can request ongoing access through the [External Researcher Access Program](https://support.claude.com/en/articles/9125743-what-is-the-external-researcher-access-program).
* We announced the deprecation of the Claude Haiku 3 model (`claude-3-haiku-20240307`), with retirement scheduled for April 20, 2026. We recommend migrating to [Claude Haiku 4.5](https://platform.claude.com/docs/en/about-claude/models/overview#latest-models-comparison). Read more in [Model deprecations](https://platform.claude.com/docs/en/about-claude/model-deprecations).
### February 17, 2026
* We've launched [Claude Sonnet 4.6](https://www.anthropic.com/news/claude-sonnet-4-6), our latest balanced model combining speed and intelligence for everyday tasks. Sonnet 4.6 delivers improved agentic search performance while consuming fewer tokens. Sonnet 4.6 supports [extended thinking](https://platform.claude.com/docs/en/build-with-claude/extended-thinking) and a [1M token context window](https://platform.claude.com/docs/en/build-with-claude/context-windows) (beta). See [Models & Pricing](https://platform.claude.com/docs/en/about-claude/models) for details.
* API [code execution](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool) is now **free when used with web search or web fetch**. Sandboxed code execution improves model capability and token efficiency. See the [pricing details](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool#usage-and-pricing) for standalone usage.
* The [web search tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/web-search-tool) and [programmatic tool calling](https://platform.claude.com/docs/en/agents-and-tools/tool-use/programmatic-tool-calling) are now generally available (no beta header required). Web search and web fetch now support [dynamic filtering](https://platform.claude.com/docs/en/agents-and-tools/tool-use/web-search-tool#dynamic-filtering), which uses code execution to filter results before they reach the context window for better performance and reduced token cost.
* The [code execution tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/code-execution-tool), [web fetch tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/web-fetch-tool), [tool search tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/tool-search-tool), [tool use examples](https://platform.claude.com/docs/en/agents-and-tools/tool-use/define-tools#providing-tool-use-examples), and [memory tool](https://platform.claude.com/docs/en/agents-and-tools/tool-use/memory-tool) are now generally available (no beta header required).
### February 7, 2026
* We've launched [fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode) in research preview for Opus 4.6, providing significantly faster output token generation through the `speed` parameter. Fast mode is up to 2.5x as fast at premium pricing. Interested customers should join the [waitlist](https://claude.com/fast-mode).
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