CLAUDE_CODE_DISABLE_CLAUDE_API_SKILL

Updated October 13, 2026 by Alex Sorokoletov

CLAUDE_CODE_DISABLE_CLAUDE_API_SKILL is a Claude Code environment variable: Disables the built-in Claude API skill. The Claude API skill auto-triggers when code imports anthropic or @anthropic-ai/sdk, providing SDK-aware guidance. In enterprise environments or when working on competing AI integrations, this automatic behavior can be unwanted. Removed between v2.1.252 and v2.1.266, so current releases ignore it. It is not in the official reference.

How to set it

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

export CLAUDE_CODE_DISABLE_CLAUDE_API_SKILL=<value>
claude

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

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

Release notes that mention it

• Claude Code v2.1.89 — 4 New Environment Variables: Agent Cost Steering, Session Resume Controls, and 50% StructuredOutput Fix

Related variables

• CLAUDE_API_SKILL_DESCRIPTION: Registration hook for the built-in "claude-api" skill that bundles Anthropic SDK docs (Python, TypeScript, Java, Go, Ruby, PHP, C#, curl) plus shared references on models, prompt caching, managed agents, and tool use.
• CLAUDE_CODE_DISABLE_CLAUDE_CODE_SKILL
• CLAUDE_CODE_DISABLE_BUNDLED_SKILLS
• CLAUDE_CODE_DISABLE_OFFICIAL_MARKETPLACE_AUTOINSTALL: Disable automatic plugin installation from marketplace.
• CLAUDE_CODE_DISABLE_POLICY_SKILLS: Disables policy-enforced skills.
• CLAUDE_CODE_HOST_SKILL_CATALOG: A JSON object ({"skills": [...]}) of 1 to 64 folder names that scopes which synced claude.ai skills a remote session loads.
• CLAUDE_CODE_DESKTOP_SKILL_SWITCHES
• CLAUDE_CODE_DISABLE_PLUGIN_FORWARDING

Frequently asked questions

All variables, searchable: Claude Code environment variables.