CLAUDE_CODE_RESUME_CACHE_WARM

Updated November 3, 2026 by Alex Sorokoletov

CLAUDE_CODE_RESUME_CACHE_WARM is a Claude Code environment variable: In remote mode, controls warming the resume cache: true force-enables it, false disables it, and otherwise a server-side setting decides whether it runs. Added in v2.1.318 and still present in v2.1.318. 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_RESUME_CACHE_WARM=<value>
claude

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

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

Related variables

• CLAUDE_CODE_RELAUNCH_RESUME_HINT_FLAGS: Holds space-separated CLI flags to reapply when relaunching to resume; the flags are validated against known options, dropped if any is invalid, and the variable is cleared once read.
• CLAUDE_CODE_RESUME_FROM_SESSION: Instructs Claude Code to bootstrap a new session's context from an existing session ID.
• CLAUDE_CODE_RESUME_INTERRUPTED_TURN: Resume an interrupted agent turn.
• CLAUDE_CODE_RESUME_INTERRUPTED_TURN_MAX_AGE_MS
• CLAUDE_CODE_RESUME_PROMPT: Set the prompt injected when resuming a session.
• CLAUDE_CODE_RESUME_REASON: Sets the reason recorded when a session resumes; accepts 1 to 64 lowercase letters and underscores, and defaults to interrupted_turn when unset or invalid.
• CLAUDE_CODE_RESUME_SESSIONSTART_HOOKS_WAIT_MS: Milliseconds that resuming a session waits for SessionStart hooks to finish before continuing; when unset, resume skips this timed wait.
• CLAUDE_CODE_RESUME_SHOWS_CUT_OFF_CALLS

Frequently asked questions

All variables, searchable: Claude Code environment variables.