CLAUDE_CODE_ENABLE_TOKEN_USAGE_ATTACHMENT
Updated by Alex Sorokoletov
CLAUDE_CODE_ENABLE_TOKEN_USAGE_ATTACHMENT is a Claude Code environment variable: Attach token usage info to messages. Present since v2.1.69 or earlier and still present in v2.1.294. It is not in the official reference.
| Status | Present in v2.1.294 |
|---|---|
| Added | Present since v2.1.69 or earlier |
| Category | Authentication |
| Official docs | Not listed |
How to set it
For one session, export it in the shell that starts Claude Code:
export CLAUDE_CODE_ENABLE_TOKEN_USAGE_ATTACHMENT=<value>
claudeTo apply it to every session, add it to the env object of a settings file:
// ~/.claude/settings.json
{
"env": {
"CLAUDE_CODE_ENABLE_TOKEN_USAGE_ATTACHMENT": "<value>"
}
}Release notes that mention it
Related variables
ANTHROPIC_AUTH_TOKEN: Alternative bearer token; takes priority over API key.CLAUDE_CODE_ENABLE_PROXY_AUTH_HELPER: Set to "1" to enable the proxy auth helper subsystem.CLAUDE_CODE_IDLE_TOKEN_THRESHOLD: Works alongside CLAUDE_CODE_IDLE_THRESHOLD_MINUTES to gate when the idle-return prompt appears.CLAUDE_CODE_MESSAGING_TOKEN: Controls access to the local inbox for cross-session messages.CLAUDE_CODE_OAUTH_REFRESH_TOKEN: OAuth refresh token.CLAUDE_CODE_OAUTH_TOKEN: Pre-configured OAuth access token.CLAUDE_CODE_OAUTH_TOKEN_FILE_DESCRIPTOR: File descriptor to read OAuth token from.CLAUDE_CODE_RESUME_TOKEN_THRESHOLD: Sets the token count threshold for session resume eligibility.
Frequently asked questions
What does CLAUDE_CODE_ENABLE_TOKEN_USAGE_ATTACHMENT do?
Attach token usage info to messages
Which Claude Code version has CLAUDE_CODE_ENABLE_TOKEN_USAGE_ATTACHMENT?
Present since v2.1.69 or earlier and still present in v2.1.294.
How do I set CLAUDE_CODE_ENABLE_TOKEN_USAGE_ATTACHMENT?
Export it before starting Claude Code (export CLAUDE_CODE_ENABLE_TOKEN_USAGE_ATTACHMENT=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.