diff --git a/src/cache.ts b/src/cache.ts
index a6b2bbc..f121bbd 100644
--- a/src/cache.ts
+++ b/src/cache.ts
@@ -3,9 +3,13 @@ import findCacheDirectory from 'find-cache-dir'
 import { existsSync } from 'fs'
 import path from 'path'
 
+import { ErrorLinkProject } from './error.js'
+
 export const createCache = () => {
   const cacheDir = findCacheDirectory({ name: 'vercel-open' })
-  const cachePath = path.resolve(cacheDir!, 'cache.json')
+  if (cacheDir === undefined) throw ErrorLinkProject()
+
+  const cachePath = path.resolve(cacheDir, 'cache.json')
 
   const cacheFilePromise = (async () => {
     try {
diff --git a/src/error.ts b/src/error.ts
new file mode 100644
index 0000000..638944b
--- /dev/null
+++ b/src/error.ts
@@ -0,0 +1,5 @@
+export const ErrorLinkProject = () => {
+  const error: NodeJS.ErrnoException = new Error('Link project error')
+  error.code = 'ERR_LINK_PROJECT'
+  throw error
+}
diff --git a/src/index.ts b/src/index.ts
index a4651f4..3f1e988 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -2,6 +2,7 @@ import { readFile } from 'fs/promises'
 import { existsSync } from 'fs'
 import path from 'path'
 
+import { ErrorLinkProject } from './error.js'
 import { createCache } from './cache.js'
 
 const cache = createCache()
@@ -51,13 +52,7 @@ async function readProjectFile (): Promise<{
   teamId: string
 }> {
   const filepath = path.resolve(process.cwd(), '.vercel/project.json')
-
-  if (!existsSync(filepath)) {
-    const error: NodeJS.ErrnoException = new Error('Link project error')
-    error.code = 'ERR_LINK_PROJECT'
-    throw error
-  }
-
+  if (!existsSync(filepath)) throw ErrorLinkProject()
   const fileContent = await readFile(filepath, 'utf-8')
   const { projectId, orgId: teamId } = JSON.parse(fileContent)
   return { projectId, teamId }