diff --git a/zyte_spider_templates/params.py b/zyte_spider_templates/params.py
index 568de72..497fe9f 100644
--- a/zyte_spider_templates/params.py
+++ b/zyte_spider_templates/params.py
@@ -83,19 +83,21 @@ class MaxRequestsParam(BaseModel):
     )
 
 
-INPUT_FIELDS = ("url", "urls", "urls_file")
+INPUT_GROUP_FIELDS = ("url", "urls", "urls_file")
 INPUT_GROUP = {
     "id": "inputs",
     "title": "Inputs",
-    "description": ("Input data that determines the start URLs of the crawl."),
+    "description": "Input data that determines the start URLs of the crawl.",
     "widget": "exclusive",
 }
 
 
-def single_input_validator(model):
-    input_fields = set(field for field in INPUT_FIELDS if getattr(model, field, None))
+def validate_input_group(model):
+    input_fields = set(
+        field for field in INPUT_GROUP_FIELDS if getattr(model, field, None)
+    )
     if not input_fields:
-        input_field_list = ", ".join(INPUT_FIELDS)
+        input_field_list = ", ".join(INPUT_GROUP_FIELDS)
         raise ValueError(
             f"No input parameter defined. Please, define one of: "
             f"{input_field_list}."
@@ -128,8 +130,8 @@ class UrlsFileParam(BaseModel):
     )
 
     @model_validator(mode="after")
-    def single_input(self):
-        return single_input_validator(self)
+    def input_group(self):
+        return validate_input_group(self)
 
 
 class UrlParam(BaseModel):
@@ -146,8 +148,8 @@ class UrlParam(BaseModel):
     )
 
     @model_validator(mode="after")
-    def single_input(self):
-        return single_input_validator(self)
+    def input_group(self):
+        return validate_input_group(self)
 
 
 class UrlsParam(BaseModel):
@@ -167,8 +169,8 @@ class UrlsParam(BaseModel):
     )
 
     @model_validator(mode="after")
-    def single_input(self):
-        return single_input_validator(self)
+    def input_group(self):
+        return validate_input_group(self)
 
     @field_validator("urls", mode="before")
     @classmethod