Next.js 16 FUNCTION_INVOCATION_FAILED on app/not-found.tsx with cacheComponents Enabled

What this error means

[regression] app/not-found.tsx throws FUNCTION_INVOCATION_FAILED server error instead of rendering the custom error page when cacheComponents are enabled is a Vercel failure pattern reported for developers trying to fix regression in next.js 16.2.6+ where not-found.tsx fails with function_invocation_failed in production when cachecomponents is enabled. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub Issue #93902 (vercel/next.js), opened 2026-05-17T11:03:25Z. Regression between 16.2.3 and 16.2.6. Production-only error causing deployment failures. Mapping: Vercel/Next.js deployment error → Deployment.

Common causes

• GitHub Issue #93902 (vercel/next.js), opened 2026-05-17T11:03:25Z. Regression between 16.2.3 and 16.2.6. Production-only error causing deployment failures. Mapping: Vercel/Next.js deployment error → Deployment.

Quick fixes

1. Confirm the exact error signature matches [regression] app/not-found.tsx throws FUNCTION_INVOCATION_FAILED server error instead of rendering the custom error page when cacheComponents are enabled.
2. Check the Vercel account, local tool state, and provider configuration involved in the failing workflow.
3. Compare the failing environment with a known working setup, then change one configuration value at a time.

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.

Sources checked

• https://github.com/vercel/next.js/issues/93902

Evidence note: GitHub Issue #93902 (vercel/next.js), opened 2026-05-17T11:03:25Z. Regression between 16.2.3 and 16.2.6. Production-only error causing deployment failures. Mapping: Vercel/Next.js deployment error → Deployment.

Related errors

• Deployment

FAQ

What should I check first?

Start with the exact [regression] app/not-found.tsx throws FUNCTION_INVOCATION_FAILED server error instead of rendering the custom error page when cacheComponents are enabled text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Vercel workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without [regression] app/not-found.tsx throws FUNCTION_INVOCATION_FAILED server error instead of rendering the custom error page when cacheComponents are enabled.