Hey Alex! I think there's a confusion with the ports here. According to the AI SDK documentation, the devtools UI is actually served on port 4983, not 5173.

When you run npx <@ai> -sdk/devtools, try accessing http://localhost:4983 directly in your browser. That's where both the API and the UI viewer are served.

The message saying Open http://localhost:5173 for the dev UI appears to be incorrect. The devtools runs everything on a single port (4983 by default).

Let me know if accessing http://localhost:4983 works for you!

https://ai-sdk.dev/docs/ai-sdk-core/devtools

ai-sdk.dev

DevTools

Debug and inspect AI SDK applications with DevTools

This is what I see at 4983:

The link takes me to 5173 which doesn’t seem to exist as you pointed out.

I dug into the code a bit. Seems this is a special mode I’m hitting that’s meant to be used to develop ai-devtools itself. The cause is this check which looks for `src` in the calling path; all of my repos are checked out under `~/src` on my laptop so I inadvertently get into that condition.

https://github.com/vercel/ai/blob/c36a873ce00892a4c587c2e9492220b392aefd09/packages/devtools/src/viewer/server.ts#L242

GitHub

ai/packages/devtools/src/viewer/server.ts at c36a873ce00892a4c587c2e9492220b392aefd09 · vercel/ai

The AI Toolkit for TypeScript. From the creators of Next.js, the AI SDK is a free open-source library for building AI-powered applications and agents - vercel/ai

I

[quote="alexturpin, post:6, topic:33308"] dug into the code a bit. Seems this is a special mode I’m hitting that’s meant to be used to develop ai-devtools itself. The cause is this check which looks for src in the calling path; all of my repos are checked out under ~/src on my laptop so I inadvertently get into that condition.

https://github.com/vercel/ai/blob/c36a873ce00892a4c587c2e9492220b392aefd09/packages/devtools/src/viewer/server.ts#L242

GitHub

ai/packages/devtools/src/viewer/server.ts at c36a873ce00892a4c587c2e9492220b392aefd09 · vercel/ai

The AI Toolkit for TypeScript. From the creators of Next.js, the AI SDK is a free open-source library for building AI-powered applications and agents - vercel/ai

I

[/quote]

Thanks - put up a fix! https://github.com/vercel/ai/pull/12394

Hi @nicoalbanese! Thanks for the fix regarding the /src/ path detection.

However, I’ve noticed this creates a new conflict for users working with Monorepos (like NX or Turborepo). In these environments, it is very common to have both /src/ and /dist/ folders existing simultaneously within the workspace or even within the same application path (e.g., apps/my-app/src and apps/my-app/dist).

Since the current logic relies on the absence of /dist/ to enable dev mode, the DevTools become inaccessible in these projects as soon as a build is generated or if the monorepo manager creates a distribution folder at the root.

Perhaps a more robust approach would be to check for an environment variable or a specific flag, rather than relying solely on string patterns in the file path, to avoid these false positives in complex project structures.

Is there a recommended way to force-enable DevTools in these cases?

Hi @nicoalbanese, hope you’re doing well!

Just wanted to follow up on the message below in case it slipped through. I’m still running into this issue in monorepo setups and wanted to check if there’s a recommended workaround or if this is something that might be addressed going forward.

Thanks again for taking a look.

Best,

Jesús.

hey! can you try again - i put through a change last week that should fix!