{"name":"ANTHROPIC_BETAS","slug":"anthropic-betas","family":"env","title":"Environment variables","noun":"environment variable","description":"Comma-separated list of additional `anthropic-beta` header values to include in API requests. Claude Code already sends the beta headers it needs; use this to opt into an [Anthropic API beta](https:\/\/platform.claude.com\/docs\/en\/api\/beta-headers) before Claude Code adds native support. Unlike the [`--betas` flag](\/docs\/en\/cli-reference#cli-flags), which requires API key authentication, this variable works with all auth methods including Claude.ai subscription","description_source":"docs","described_by":{"doc":"claude-code\/env-vars","title":"Environment variables"},"presence":{"first_seen":"2.1.138","removed_in":null,"in_current_build":true,"newest_mined":"2.1.308","builds":149,"mined_builds":149,"first_cited":{"version":"2.1.260","released_at":"2026-09-03 22:32:02","spans":1}},"aliases":[],"entries":[{"version":"2.1.299","anchor":"anthropic-betas-skips-a-beta-that-is-now-generally-available","heading":"ANTHROPIC_BETAS no longer sends a beta that is now generally available","line":"A beta listed in `ANTHROPIC_BETAS` that is now generally available is dropped from requests, and a debug message says so","released_at":"2026-10-14 00:23:19","reason":"found in this entry's text, named in this entry"},{"version":"2.1.267","anchor":"org-policy-beta-block-message-reworded","heading":"Org-policy beta-block message reworded","line":"The message shown when an org policy blocks experimental beta headers was reworded","released_at":"2026-09-09 18:25:42","reason":"found in this entry's text"},{"version":"2.1.267","anchor":"anthropic-betas-values-now-filtered-through-a-new-exclusion","heading":"ANTHROPIC_BETAS values now filtered through a new exclusion list before being applied","line":"ANTHROPIC_BETAS entries are now filtered against a new exclusion list before being applied","released_at":"2026-09-09 18:25:42","reason":"found in this entry's text, named in this entry"},{"version":"2.1.260","anchor":"anthropic-betas-env-var-can-be-blocked-by-org-compliance-pol","heading":"ANTHROPIC_BETAS env var can be blocked by org compliance policy","line":"Org compliance policy can now block the ANTHROPIC_BETAS environment variable entirely.","released_at":"2026-09-03 22:32:02","reason":"found in this entry's text, named in this entry"},{"version":"2.1.78","anchor":"bug-fixes","heading":"","line":null,"released_at":"2026-03-17 21:04:05","reason":"found in this entry's text"},{"version":"0.2.104","anchor":"beta-features","heading":"","line":null,"released_at":"2025-05-07 19:53:37","reason":"found in this entry's text"}],"entries_total":6,"docs":[{"source":"claude-code","path":"env-vars","title":"Environment variables","documented":true},{"source":"claude-code","path":"llm-gateway-protocol","title":"Claude Code gateway compatibility guide","documented":false}],"docs_total":2,"gates":[],"related":[{"name":"ANTHROPIC_API_KEY","slug":"anthropic-api-key","description":"API key sent as `X-Api-Key` header. When set, this key is used instead of your Claude Pro, Max, Team, or Enterprise subscription even if you are logged in. In non-interactive mode (`-p`), the key is always used when present. In interactive mode, you are prompted to approve the key once before it overrides your subscription. To use your subscription instead, run `unset ANTHROPIC_API_KEY`"},{"name":"ANTHROPIC_AUTH_TOKEN","slug":"anthropic-auth-token","description":"Custom value for the `Authorization` header (the value you set here will be prefixed with `Bearer `)"},{"name":"ANTHROPIC_AWS_API_KEY","slug":"anthropic-aws-api-key","description":"Workspace API key for [Claude Platform on AWS](\/docs\/en\/claude-platform-on-aws), generated in the AWS Console. Sent as `x-api-key` and takes precedence over AWS SigV4"},{"name":"ANTHROPIC_AWS_BASE_URL","slug":"anthropic-aws-base-url","description":"Override the [Claude Platform on AWS](\/docs\/en\/claude-platform-on-aws) endpoint URL. Use for custom regions or when routing through an [LLM gateway](\/docs\/en\/llm-gateway). Defaults to `https:\/\/aws-external-anthropic.{region}.api.aws`. Claude Code resolves the region with the [same precedence as on Amazon Bedrock](\/docs\/en\/amazon-bedrock#3-configure-claude-code)"},{"name":"ANTHROPIC_AWS_WORKSPACE_ID","slug":"anthropic-aws-workspace-id","description":"Required for [Claude Platform on AWS](\/docs\/en\/claude-platform-on-aws). Sent on every request as the `anthropic-workspace-id` header"},{"name":"ANTHROPIC_BASE_URL","slug":"anthropic-base-url","description":"Override the API endpoint to route requests through a proxy or gateway. When set to a non-first-party host, [MCP tool search](\/docs\/en\/mcp#scale-with-mcp-tool-search) is disabled by default. Set `ENABLE_TOOL_SEARCH=true` if your proxy forwards `tool_reference` blocks. As of v2.1.196, [Remote Control](\/docs\/en\/remote-control#requirements) is disabled when this points at a host other than `api.anthropic.com`, matching its behavior on Amazon Bedrock, Google Cloud's Agent Platform, and Microsoft Foundry"},{"name":"ANTHROPIC_BEDROCK_BASE_URL","slug":"anthropic-bedrock-base-url","description":"Override the Amazon Bedrock endpoint URL. Use for custom Amazon Bedrock endpoints or when routing through an [LLM gateway](\/docs\/en\/llm-gateway). See [Amazon Bedrock](\/docs\/en\/amazon-bedrock)"},{"name":"ANTHROPIC_BEDROCK_MANTLE_BASE_URL","slug":"anthropic-bedrock-mantle-base-url","description":"Override the Amazon Bedrock Mantle endpoint URL. See [Mantle endpoint](\/docs\/en\/amazon-bedrock#use-the-mantle-endpoint)"},{"name":"ANTHROPIC_BEDROCK_REGION_PREFIX","slug":"anthropic-bedrock-region-prefix","description":"Cross-region inference profile prefix (`us`, `eu`, `apac`, `jp`, `au`, or `global`) Claude Code tries first instead of the one derived from the AWS region. Ignored in AWS GovCloud regions. Requires Claude Code v2.1.224 or later. See [Amazon Bedrock](\/docs\/en\/amazon-bedrock#cross-region-inference-profile-prefixes)"},{"name":"ANTHROPIC_BEDROCK_SERVICE_TIER","slug":"anthropic-bedrock-service-tier","description":"Amazon Bedrock [service tier](https:\/\/docs.aws.amazon.com\/bedrock\/latest\/userguide\/service-tiers-inference.html) (`default`, `flex`, or `priority`). Sent as the `X-Amzn-Bedrock-Service-Tier` header. See [Amazon Bedrock](\/docs\/en\/amazon-bedrock#service-tiers)"}],"url":"https:\/\/changelogs.core-directive.com\/reference\/env\/anthropic-betas","family_url":"https:\/\/changelogs.core-directive.com\/reference\/env.json"}