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

  1. Confirm the exact error signature matches ApiError: Forbidden { error: 'Authentication error' } — misleading: actually requires Workers Paid plan.
  2. Check the Cloudflare account, local tool state, and provider configuration involved in the failing workflow.
  3. 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

  1. Capture the exact error message and the command, editor action, or request that triggered it.
  2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
  3. Review the source evidence below and compare it with your environment.
  4. Apply one change at a time and rerun the smallest failing action.
  5. 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.