vercel/next.js · error

Route ${workStore.route} used "${expression}" inside a funct

Error message

Route ${workStore.route} used "${expression}" inside a function cached with `unstable_cache()`. The enabled status of `draftMode()` can be read in caches but you must not enable or disable `draftMode()` inside a cache. See more info here: https://nextjs.org/docs/app/api-reference/functions/unstable_cache

What it means

Error "Route ${workStore.route} used "${expression}" inside a function cached with `unstable_cache()`. The enabled status of `draftMode()` can be read in caches but you must not enable or disable `draftMode()` inside a cache. See more info here: https://nextjs.org/docs/app/api-reference/functions/unstable_cache" thrown in vercel/next.js.

Source

Thrown at packages/next/src/server/request/draft-mode.ts:222

      throw new StaticGenBailoutError(
        `Route ${workStore.route} with \`dynamic = "error"\` couldn't be rendered statically because it used \`${expression}\`. See more info here: https://nextjs.org/docs/app/building-your-application/rendering/static-and-dynamic#dynamic-rendering`
      )
    }

    if (workUnitStore) {
      switch (workUnitStore.type) {
        case 'cache':
        case 'private-cache': {
          const error = new Error(
            `Route ${workStore.route} used "${expression}" inside "use cache". The enabled status of \`draftMode()\` can be read in caches but you must not enable or disable \`draftMode()\` inside a cache. See more info here: https://nextjs.org/docs/messages/next-request-in-use-cache`
          )
          Error.captureStackTrace(error, constructorOpt)
          applyOwnerStack(error)
          workStore.invalidDynamicUsageError ??= error
          throw error
        }
        case 'unstable-cache':
          throw new Error(
            `Route ${workStore.route} used "${expression}" inside a function cached with \`unstable_cache()\`. The enabled status of \`draftMode()\` can be read in caches but you must not enable or disable \`draftMode()\` inside a cache. See more info here: https://nextjs.org/docs/app/api-reference/functions/unstable_cache`
          )

        case 'prerender':
        case 'prerender-runtime': {
          const error = new Error(
            `Route ${workStore.route} used ${expression} without first calling \`await connection()\`. See more info here: https://nextjs.org/docs/messages/next-prerender-sync-headers`
          )
          return abortAndThrowOnSynchronousRequestDataAccess(
            workStore.route,
            expression,
            error,
            workUnitStore
          )
        }
        case 'prerender-client':
        case 'validation-client':
          const exportName = '`draftMode`'

View on GitHub (pinned to 0eb3775416)

Solutions

1. Do not enable/disable draftMode() inside unstable_cache; read isEnabled only, or move mutation outside the cache.

When it happens

Trigger: draftMode enable/disable is called inside unstable_cache.

Common situations: Mutating draft mode inside a cached function; only reading the enabled status is allowed.

AI-assisted analysis of vercel/next.js@0eb3775416 (2026-08-19). Data as JSON: /api/errors/2c4fed8261753778. Report an issue: GitHub.