Sidecar fails with 'Missing Authentication header' when API keys are in ~/.zshrc

[ellisjr]

Summary

Sidecar CLI fails with Missing Authentication header when API keys (GOOGLE_GENERATIVE_AI_API_KEY, OPENAI_API_KEY) are exported in ~/.zshrc but not in ~/.zshenv. This affects all headless (--no-ui) and interactive invocations when launched from non-interactive shells (e.g., Claude Code's Bash tool, CI/CD, scripts).

Steps to Reproduce

1. Export API keys in ~/.zshrc (not ~/.zshenv)
2. Run sidecar from a non-interactive shell context (e.g., Claude Code, a Node script, cron):

   sidecar start --model gemini --prompt "Hello" --no-ui

3. Observe: {"level":"error","msg":"Session error detected","error":"APIError","message":"Missing Authentication header"}

Workaround: source ~/.zshrc && sidecar start ... — works but fragile.

Root Cause

Sidecar is a Node.js script (#!/usr/bin/env node) that inherits environment from its parent shell. When the parent is non-interactive (common for tool-spawned processes), zsh only sources ~/.zshenv — not ~/.zshrc.

Shell Mode	Sources .zshrc?	Keys Available?
zsh (non-interactive)	No	No
zsh -l (login)	No	No
zsh -i (interactive)	Yes	Yes
Terminal.app / iTerm	Yes	Yes
Claude Code Bash tool	No	No
source ~/.zshrc && sidecar	Forced	Yes (workaround)

Expected Behavior

Sidecar should either:

1. Document the requirement that API keys must be in ~/.zshenv (not ~/.zshrc) for non-interactive shell compatibility — the setup docs currently say "Add these to your shell profile (~/.bashrc, ~/.zshrc)" which is misleading for zsh
2. Auto-detect and warn when running in a non-interactive shell without required API keys, with a message like: "API key not found. If your keys are in ~/.zshrc, move them to ~/.zshenv for non-interactive shell support"
3. Attempt to source common profile files as a fallback when keys are missing

Environment

• macOS 14.5 (Darwin 23.5.0)
• zsh (default shell)
• sidecar installed via npm (/usr/local/bin/sidecar)
• Claude Code as parent process
• ~/.local/share/opencode/auth.json had placeholder value

Additional Context

The sidecar skill docs recommend ~/.bashrc and ~/.zshrc for key placement. For bash users this works fine (.bashrc is sourced by non-interactive bash when BASH_ENV is set). For zsh users, this is a silent failure mode — keys appear to work in terminals but fail in automated/tool contexts.

🤖 Generated with Claude Code