Claude Code · tool · fg-0480

claude --bare -p fails to authenticate although the normal session is signed in with Pro or Max

A --bare run fails on authentication while the same command without --bare works

Verified 2026-10-15 · Confirmed by 0 builders · Trust 50/100

Cause

Bare mode never reads OAuth credentials or the system keychain, so a Claude subscription login is not used. Amazon Bedrock, Google Cloud, and Microsoft Foundry keep reading their own credentials.

Fix

Set ANTHROPIC_API_KEY to a key created in the Claude Console, or supply an apiKeyHelper in the --settings JSON.

Apply

claude --bare -p "task" --settings '{"apiKeyHelper": "~/bin/get-anthropic-key.sh"}'

Affects: Claude Code --bare mode, as of 2026-10

Sources

https://code.claude.com/docs/en/headless

Have your agent know this before it fails

claude mcp add --transport http footgun https://getfootgun.com/api/mcp