CLAUDE_CODE_PEWTER_OWL_TOOL

Updated October 14, 2026 by Alex Sorokoletov

CLAUDE_CODE_PEWTER_OWL_TOOL is a Claude Code environment variable. Added between v2.1.143 and v2.1.212 and still present in v2.1.295. It is not in the official reference.

Status	Present in v2.1.295
Added	Added between v2.1.143 and v2.1.212
Category	Shell and tools
Official docs	Not listed

How to set it

For one session, export it in the shell that starts Claude Code:

export CLAUDE_CODE_PEWTER_OWL_TOOL=<value>
claude

To apply it to every session, add it to the env object of a settings file:

// ~/.claude/settings.json
{
  "env": {
    "CLAUDE_CODE_PEWTER_OWL_TOOL": "<value>"
  }
}

Related variables

CLAUDE_CODE_DISABLE_ADVISOR_TOOL: Disables what appears to be an internal advisory tool.
CLAUDE_CODE_EMIT_TOOL_USE_SUMMARIES: Emit tool use summary events.
CLAUDE_CODE_ENABLE_EXPERIMENTAL_ADVISOR_TOOL: Enables the experimental Advisor Tool — a server-side tool with its own advisorModel config option.
CLAUDE_CODE_MAX_TOOL_USE_CONCURRENCY: Max concurrent tool executions; default 10.
CLAUDE_CODE_TOOL_MEMORY_CGROUP_EXCLUDE
CLAUDE_CODE_TOOL_MEMORY_LIMIT
CLAUDE_CODE_USE_POWERSHELL_TOOL: Enables a PowerShell-specific tool variant for Windows environments.
ENABLE_LSP_TOOL: Enable Language Server Protocol tool.

Frequently asked questions

Which Claude Code version has CLAUDE_CODE_PEWTER_OWL_TOOL?

Added between v2.1.143 and v2.1.212 and still present in v2.1.295.

How do I set CLAUDE_CODE_PEWTER_OWL_TOOL?

Export it before starting Claude Code (export CLAUDE_CODE_PEWTER_OWL_TOOL=value), or add it to the "env" object in ~/.claude/settings.json to apply it to every session.

All variables, searchable: Claude Code environment variables.