Error: Authentication failed: No API key found for anthropic.

Use /login to log into a provider via OAuth or API key. See:
/home/runner/work/_actions/getsentry/warden/v0/dist/action/docs/providers.md
/home/runner/work/_actions/getsentry/warden/v0/dist/action/docs/models.md

export WARDEN_MODEL=provider/model-id # e.g. openai/gpt-5.5
export WARDEN_{PROVIDER}_API_KEY=... # WARDEN-prefixed key for that provider

See https://warden.sentry.dev/config/models for provider selectors and credential names.