Beta Header Constants

A list of beta header strings for enabling experimental Claude API features. Pass these to the beta parameter of claude_new().

Usage

beta_headers

Format

A named list with 13 elements:

BETA_1M_CONTEXT

"context-1m-2025-08-07" - 1 million token context window (Sonnet only)

BETA_INTERLEAVED

"interleaved-thinking-2025-05-14" - Interleaved thinking between tool calls

BETA_COMPUTER_USE

"computer-use-2025-01-24" - Computer control capabilities

BETA_CODE_EXEC_BASH

"code-execution-2025-08-25" - Bash code execution

BETA_CODE_EXEC_PYTHON

"code-execution-2025-05-22" - Python code execution

BETA_128K_OUTPUT

"output-128k-2025-02-19" - Extended output length

BETA_FILES_API

"files-api-2025-04-14" - Files API for uploads

BETA_EFFORT

"effort-2025-11-24" - Token efficiency control (Opus 4.5 only)

BETA_SKILLS

"skills-2025-10-02" - Agent Skills for specialized tasks

BETA_CONTEXT_MGMT

"context-management-2025-06-27" - Memory and context editing

BETA_TOOL_SEARCH

"tool-search-tool-2025-10-19" - Dynamic tool discovery

BETA_ADVANCED_TOOLS

"advanced-tool-use-2025-11-20" - Programmatic tool calling

BETA_TOKEN_EFFICIENT

"token-efficient-tools-2025-02-19" - Token-efficient tool responses

Source

https://docs.anthropic.com/en/docs/beta-features

Details

Access individual headers using list syntax: beta_headers$BETA_1M_CONTEXT

These headers enable experimental features that may change. Check Anthropic's documentation for current availability and requirements.

See also

Other claude-tools: claude-tools, claude_code_exec(), claude_context_edit(), claude_memory(), claude_text_editor(), claude_tool(), claude_tool_defer(), claude_tool_programmatic(), claude_web_fetch(), claude_web_search()

Examples

if (FALSE) { # \dontrun{
# Use 1M context window (Sonnet only)
chat <- claude_new(
  ml = "claude-sonnet-4-5-20250929",
  beta = beta_headers$BETA_1M_CONTEXT
)

# Combine multiple betas
chat <- claude_new(
  beta = c(beta_headers$BETA_CODE_EXEC_BASH, beta_headers$BETA_FILES_API)
)

# Code execution with Python
chat <- claude_new(
  tools = list(claude_code_exec(type = "python")),
  beta = beta_headers$BETA_CODE_EXEC_PYTHON
)
} # }