diff --git a/src/inputs/run-install.ts b/src/inputs/run-install.ts
index e4858cf..d7215b7 100644
--- a/src/inputs/run-install.ts
+++ b/src/inputs/run-install.ts
@@ -2,37 +2,28 @@ import { getInput, error } from '@actions/core'
 import * as yaml from 'yaml'
 import { z, ZodError } from 'zod'
 
-export interface RunInstall {
-  readonly recursive?: boolean
-  readonly cwd?: string
-  readonly args?: readonly string[]
-}
-
-const zRunInstall = z.object({
+const RunInstallSchema = z.object({
   recursive: z.boolean().optional(),
   cwd: z.string().optional(),
   args: z.array(z.string()).optional(),
 })
 
-export type RunInstallInput =
-  | null
-  | boolean
-  | RunInstall
-  | RunInstall[]
-
-const zRunInstallInput = z.union([
+const RunInstallInputSchema = z.union([
   z.null(),
   z.boolean(),
-  zRunInstall,
-  z.array(zRunInstall),
+  RunInstallSchema,
+  z.array(RunInstallSchema),
 ])
 
+export type RunInstallInput = z.infer<typeof RunInstallInputSchema>
+export type RunInstall = z.infer<typeof RunInstallSchema>
+
 export function parseRunInstall(inputName: string): RunInstall[] {
   const input = getInput(inputName, { required: true })
   const parsedInput: unknown = yaml.parse(input)
 
   try {
-    const result: RunInstallInput = zRunInstallInput.parse(parsedInput)
+    const result: RunInstallInput = RunInstallInputSchema.parse(parsedInput)
     if (!result) return []
     if (result === true) return [{ recursive: true }]
     if (Array.isArray(result)) return result