CLAUDE_CODE_PRINT_ENGINE_LOOP

Updated October 14, 2026 by Alex Sorokoletov

CLAUDE_CODE_PRINT_ENGINE_LOOP is a Claude Code environment variable. Removed between v2.1.252 and v2.1.266, so current releases ignore it. It is not in the official reference.

Status	Removed between v2.1.252 and v2.1.266
Added	Added in v2.1.238
Category	Other
Official docs	Not listed

How to set it

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

export CLAUDE_CODE_PRINT_ENGINE_LOOP=<value>
claude

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

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

Related variables

CLAUDE_CODE_LOOP_PERSISTENT: Persist loop state across session boundaries.
CLAUDE_CODE_DIR_SYNC_ENGINE
CLAUDE_CODE_LOOP_KEEPALIVE
ANTHROPIC_BETAS: Comma-separated beta feature headers.
ANTHROPIC_CUSTOM_HEADERS: Custom HTTP headers (newline-separated Key: Value).
ANTHROPIC_FEDERATION_RULE_ID
ANTHROPIC_ORGANIZATION_ID
ANTHROPIC_WORKSPACE_ID

Frequently asked questions

Which Claude Code version has CLAUDE_CODE_PRINT_ENGINE_LOOP?

Removed between v2.1.252 and v2.1.266, so current releases ignore it.

How do I set CLAUDE_CODE_PRINT_ENGINE_LOOP?

Export it before starting Claude Code (export CLAUDE_CODE_PRINT_ENGINE_LOOP=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.