What this error means
ApiError: Forbidden { error: 'Authentication error' } — misleading: actually requires Workers Paid plan is a Cloudflare failure pattern reported for developers trying to fix cloudflare containers deploy 403 authentication error on free plan. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.
Why this happens
Free plan account with correct API token (Workers Scripts Edit + Cloudflare Images Edit). Docker image builds successfully. wrangler deploy returns 403 with {error: 'Authentication error'}. Actual issue is plan requirement, not token permissions.
Common causes
- Deploying Workers with [[containers]] config on Free plan returns generic 403 'Authentication error'. The real issue is Containers requires Workers Paid plan, but error suggests wrong API token. Wastes time debugging token permissions.
- Free plan account with correct API token (Workers Scripts Edit + Cloudflare Images Edit). Docker image builds successfully. wrangler deploy returns 403 with {error: 'Authentication error'}. Actual issue is plan requirement, not token permissions.
Quick fixes
- Confirm the exact error signature matches
ApiError: Forbidden { error: 'Authentication error' } — misleading: actually requires Workers Paid plan. - Check the Cloudflare account, local tool state, and provider configuration involved in the failing workflow.
- Verify the account session, API key, provider settings, and environment where the failing tool is running.
Platform/tool-specific checks
- Verify the command, editor, extension, or API client that produced the error.
- Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
- Avoid deleting credentials, local model data, or project settings until the failing scope is clear.
Step-by-step troubleshooting
- Capture the exact error message and the command, editor action, or request that triggered it.
- Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
- Review the source evidence below and compare it with your environment.
- Apply one change at a time and rerun the smallest failing action.
- Keep the working fix documented for the team or deployment environment.
How to prevent it
- Keep provider/tool configuration documented.
- Record non-secret diagnostics such as tool version, provider name, model name, and command path.
- Add a lightweight check before CI or production workflows depend on the tool.