CLAUDE_BG_SOURCE

Updated October 13, 2026 by Alex Sorokoletov

CLAUDE_BG_SOURCE is a Claude Code environment variable: Tags where a background job originated: CLI, SDK, Remote Control, another agent. Present on the daemon side so it can route, prioritize, or attribute work without the originator being alive when the job finishes. Added between v2.1.118 and v2.1.123 and still present in v2.1.294. 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_BG_SOURCE=<value>
claude

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

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

Release notes that mention it

• Claude Code v2.1.123 — Background Daemons, Agent Fleets, and CoWork Memory
• Claude Code Version Tracker: Undocumented Env Vars, Feature Gates & Models

Related variables

• CLAUDE_CODE_BRIDGE_SOURCE_DIR
• CLAUDE_CODE_RESUME_SOURCE_ALIVE
• CLAUDE_AUTO_BACKGROUND_TASKS: Enable automatic background task execution.
• CLAUDE_BG_BACKEND: Set to "daemon" to route background work through a daemon backend.
• CLAUDE_BG_ISOLATION: Isolation mode for background agent processes — controls how separated the daemon's process space is from the foreground session.
• CLAUDE_BG_RENDEZVOUS_SOCK: Socket path for the IPC channel between a foreground Claude session and the background daemon.
• CLAUDE_BG_STARTUP_WEDGE_MS: Startup jitter for background sessions.
• CLAUDE_BG_TCC_DISCLAIMED: macOS TCC (Transparency, Consent, and Control) permission disclaimer state for background sessions.

Frequently asked questions

All variables, searchable: Claude Code environment variables.