CLAUDE_CODE_SIMULATE_PROXY_USAGE

Updated October 13, 2026 by Alex Sorokoletov

CLAUDE_CODE_SIMULATE_PROXY_USAGE is a Claude Code environment variable: Simulates proxy-based API routing without an actual proxy. This is a testing tool — it lets developers verify that their Claude Code configuration behaves correctly when routed through a corporate proxy, without needing the proxy infrastructure in place. Removed in v2.1.294, 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_SIMULATE_PROXY_USAGE=<value>
claude

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

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

Release notes that mention it

• Claude Code v2.1.92 — 5 New Environment Variables: Proxy Simulation, Fast Mode Bypass, and Remote Session Naming
• Claude Code Version Tracker: Undocumented Env Vars, Feature Gates & Models

Related variables

• CLAUDE_CODE_HOST_HTTP_PROXY_PORT: HTTP proxy port for host.
• CLAUDE_CODE_HOST_SOCKS_PROXY_PORT: SOCKS proxy port for host.
• CLAUDE_CODE_HTTP_PROXY: Claude-namespaced HTTP proxy URL.
• CLAUDE_CODE_HTTPS_PROXY: Claude-namespaced HTTPS proxy URL.
• CLAUDE_CODE_PROXY_HOST: Proxy hostname, passed alongside the URL so helpers that route credentials by hostname don't need to re-parse.
• CLAUDE_CODE_PROXY_RESOLVES_HOSTS: Proxy handles DNS resolution (skip local DNS).
• CLAUDE_CODE_PROXY_URL: Full proxy URL, injected into the helper subprocess's environment.
• HTTP_PROXY: HTTP proxy server URL.

Frequently asked questions

All variables, searchable: Claude Code environment variables.