Hey, I am seeking help with on-demand revalidation. Usually I call it in server actions, and there are no issues with that.

This time I use route.ts (I am using useChat from AI SDK, need an endpoint), and I want to check if user has any remaining credits left, if no I want to revalidate specific path, to stop displaying the chat. It should not be visible on the page DURING NEXT VISIT/AFTER REFRESH, not during current session.

That's crucial part of route handler:

const remainingBalance = ...;
const result = streamText({
      model: ...,

      messages,
      system: ...,
      maxOutputTokens,
      onFinish: async ({ totalUsage }) => {
        logger.info('On-page AI Assistant: Response finished', {
          userId: user.id,
          ...totalUsage,
        });

        const totalTokens = totalUsage.totalTokens;
        await AIService.trackAITokensUsage(user.id, {
          totalTokens,
        });

        if (remainingBalance - totalTokens <= 0) {
          logger.warn('On-page AI Assistant: Page owner has no remaining balance after request', {
            userId: user.id,
            slug,
            remainingBalance,
            totalTokens
          });

          logger.info(
            `[REVALIDATION]: HITTING REVALIDATION FOR ${url.composePathname(Path.Page, slug)}`,
          );
     
          // no results from this call, I would expect revalidation of `/page/${slug}`
          revalidatePath(url.composePathname(Path.Page, slug));
        }
      },
    });

    return result.toUIMessageStreamResponse();

Some facts:
- the path is 100% correct, I use the same code to revalidate pages in other places (however in server actions).
- Next.js 15.4.2
- AI 5.0.0-beta.20
- Vercel dashboard clearly shows all logs are triggered
- Desired page (that should be revalidated) uses ISR, can be revalidated by different calls (SA)