What's new in Claude

Claude API·Jun 26, 2026

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, 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.

Claude API·Jun 25, 2026

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 4.8. Read more in Fast mode.

Claude API·Jun 22, 2026

MCP tunnels: the management API moved from /v1/organizations/tunnels on the Admin API to /v1/tunnels on the…

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.

Claude API·Jun 18, 2026

The Python, TypeScript, Go, Java, Ruby, PHP, and C# SDKs now include support for code_execution_20260120,…

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 code execution tool's Compatibility section.

Claude API·Jun 15, 2026

We've retired the Claude Sonnet 4 model and the Claude Opus 4 model

All requests to these models on the Claude API will now return an error. We recommend upgrading to Claude Sonnet 4.6 and Claude Opus 4.8 respectively. Researchers can request ongoing access through the External Researcher Access Program.

Claude API·Jun 11, 2026

The code execution tool now supports code_execution_20260521, which discloses the 90-second per-cell…

No beta header is required. The web search tool and 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.

Claude API·Jun 10, 2026

The GET /v1/environments/{id}/work endpoint, which lists pending work for a self-hosted sandbox, is now…

Claude API·Jun 9, 2026

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 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. The stop_details.category 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. On Claude Fable 5 and Claude Mythos 5, adaptive 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). 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. Claude Fable 5 requires 30-day data retention and is not available under zero data retention. Claude Managed Agents now supports scheduled deployments, letting you run sessions on a cron schedule without managing your own scheduler. Claude Managed Agents vaults now support environment variable credentials, 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 Activity Feed (GET /v1/compliance/activities) is now available on Claude Platform on AWS. 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 in beta that adds Claude as a server-side LanguageModel in Apple's Foundation Models framework.

Claude API·Jun 5, 2026

We announced the deprecation of the Claude Opus 4.1 model, with retirement on the Claude API scheduled for…

We recommend migrating to Claude Opus 4.8. Read more in Model deprecations.

Claude API·Jun 2, 2026

The advisor tool now supports a max_tokens parameter to cap the advisor model's output per call, reducing…

Set tools[].max_tokens on the advisor tool definition; see 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.

Claude API·May 29, 2026

Claude Managed Agents webhooks, multiagent orchestration, and self-hosted sandboxes are now available on…

Claude API·May 28, 2026

We've launched mid-conversation system messages

On Claude Opus 4.8, you can send role: "system" messages after a user turn (subject to placement rules) in the messages array, preserving prompt cache hits when instructions change during a long-running session. No beta header is required. The stop_details 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. On Claude Opus 4.8, the effort parameter 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 is 1,024 tokens, lower than on Claude Opus 4.7. With adaptive 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 (up to 2576 pixels on the long edge), same as Claude Opus 4.7. Task budgets now support Claude Opus 4.8. The advisor tool now supports Claude Opus 4.8. Computer use now supports Claude Opus 4.8. 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. In Claude Code, we've expanded Auto mode to more users for long-running tasks. In Claude Code, Max plan users now default to fast mode on Claude Opus 4.8. In Claude Code, Workflows are available as a research preview, letting you define and run multistep agentic plans. We've deprecated fast mode for Claude Opus 4.6, with removal approximately 30 days after launch. For updates to claude.ai, Cowork, Claude for Microsoft 365, and other Claude apps in this release, see the release notes for Claude Apps.

Claude API·May 27, 2026

The Messages API response now includes usage.output_tokens_details.thinking_tokens, reporting how many of…

When streaming, the breakdown appears only on the final message_delta event. No beta header is required.

Claude API·May 19, 2026

MCP tunnels 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. 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.

Claude API·May 18, 2026

The web search tool now returns richer SEC filing data, making it easier to ground financial research…

Claude API·May 13, 2026

We've launched 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.

Claude API·May 12, 2026

Fast mode 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.

Claude API·May 6, 2026

Multiagent orchestration and Outcomes are now in public beta under the standard managed-agents-2026-04-01…

Claude Managed Agents vault credential background refresh is now supported for mcp_oauth credentials. Webhooks for Claude Managed Agents are now supported. Additional filtering and sorting options are now supported for Claude Managed Agents. Dreams for Claude Managed Agents are now available as a research preview.

Claude API·May 4, 2026

We've launched Workload Identity Federation

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.

Claude API·Apr 30, 2026

We've retired the 1M token context window beta 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 or Claude Opus 4.6, where it's included at standard pricing with no beta header required.

Claude API·Apr 29, 2026

We've released the Claude API skill, an open-source Agent Skill that gives Claude up-to-date reference…

The skill is bundled with Claude Code and available in the Anthropic skills repository.

Claude API·Apr 24, 2026

We've released the Rate Limits API, allowing administrators to programmatically query the rate limits…

Claude API·Apr 23, 2026

Memory for Claude Managed Agents is now in public beta under the standard managed-agents-2026-04-01 header

Claude API·Apr 20, 2026

We've retired the Claude Haiku 3 model

All requests to this model will now return an error. We recommend upgrading to Claude Haiku 4.5.

Claude API·Apr 16, 2026

We've launched Claude Opus 4.7, our most capable widely released model for complex reasoning and agentic…

Opus 4.7 includes API breaking changes versus Opus 4.6; see the migration guide before upgrading. Claude in Amazon Bedrock is now open to all Amazon Bedrock customers. We've launched task budgets in beta on Claude Opus 4.7. Claude Opus 4.7 supports high-resolution image input, 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. We've added the xhigh 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.

Claude API·Apr 14, 2026

We announced the deprecation of the Claude Sonnet 4 model and the Claude Opus 4 model, with retirement on…

We recommend migrating to Claude Sonnet 4.6 and Claude Opus 4.8 respectively. Read more in Model deprecations.

Claude API·Apr 9, 2026

We've launched the 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.

Claude API·Apr 8, 2026

We've launched the ant CLI, a command-line client for the Claude API that enables faster interaction with…

Learn more in the CLI quickstart.

Claude API·Apr 7, 2026

We announced Claude Mythos Preview is available as a gated research preview for defensive cybersecurity work…

Access is invitation-only. The Messages API is now available on Amazon Bedrock as a research preview.