diff --git a/src/action.ts b/src/action.ts
index 89ebac0c..2b51e8d1 100644
--- a/src/action.ts
+++ b/src/action.ts
@@ -10,7 +10,7 @@ import { envSchema, PluginInputs, pluginSettingsSchema, pluginSettingsValidator
 export async function run() {
   const payload = github.context.payload.inputs;
 
-  const env = Value.Decode(envSchema, payload.env);
+  const env = Value.Decode(envSchema, payload.env || {});
   const settings = Value.Decode(pluginSettingsSchema, Value.Default(pluginSettingsSchema, JSON.parse(payload.settings)));
 
   if (!pluginSettingsValidator.test(settings)) {