Link to the code that reproduces this issue

https://github.com/davecarlson/nextjs-route-handler-rsc-routes-repro

To Reproduce

To Reproduce

1. Clone https://github.com/davecarlson/nextjs-route-handler-rsc-routes-repro
2. npm install
3. npm run build
4. npm run verify:files

Current vs. Expected behavior

I see an extra file being created, meaning on large projects you can hit the Routes created per Deployment in 2x time.

I expect the number of handlers outputs to match the number of route handlers, and the extra .rsc .rsc.segment to not be created

For example, this gets created:
/api/[tenantId].rsc
/api/[tenantId]
/api/[tenantId]/items.rsc
/api/[tenantId]/items
/api/[tenantId]/items/[itemId].rsc
/api/[tenantId]/items/[itemId]

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 25.6.0: Fri Jul 31 19:19:08 PDT 2026; root:xnu-12377.161.14~5/RELEASE_ARM64_T6050
  Available memory (MB): 65536
  Available CPU cores: 18
Binaries:
  Node: 24.18.0
  npm: 11.16.0
  Yarn: N/A
  pnpm: N/A
Relevant Packages:
  next: 16.3.1 // Latest available version is detected (16.3.1).
  eslint-config-next: N/A
  react: 19.2.8
  react-dom: 19.2.8
  typescript: N/A
Next.js Config:
  output: N/A

Which area(s) are affected? (Select all that apply)

Route Handlers, Dynamic Routes, Output

Which stage(s) are affected? (Select all that apply)

Build (Local), Vercel (Deployed)

Additional context

Checked with latest canary build - same issue exists.

I have a vercel build that fails due to hitting the limit : AhJzCWvPRMin8Lez85Q2CQQcqYn4