diff --git a/src/openjd/model/v2023_09/_model.py b/src/openjd/model/v2023_09/_model.py
index 1255017c..6ad0a86a 100644
--- a/src/openjd/model/v2023_09/_model.py
+++ b/src/openjd/model/v2023_09/_model.py
@@ -1363,8 +1363,8 @@ class JobStringParameterDefinition(OpenJDModel_v2023_09, JobParameterInterface):
     def _validate_min_length(cls, value: Optional[int]) -> Optional[int]:
         if value is None:
             return value
-        if value <= 0:
-            raise ValueError("Required: 0 < minLength.")
+        if value < 0:
+            raise ValueError("Required: 0 <= minLength.")
         return value
 
     @field_validator("maxLength")
@@ -1607,8 +1607,8 @@ class JobPathParameterDefinition(OpenJDModel_v2023_09, JobParameterInterface):
     def _validate_min_length(cls, value: Optional[int]) -> Optional[int]:
         if value is None:
             return value
-        if value <= 0:
-            raise ValueError("Required: 0 < minLength.")
+        if value < 0:
+            raise ValueError("Required: 0 <= minLength.")
         return value
 
     @field_validator("maxLength")
diff --git a/test/openjd/model/v2023_09/test_job_parameters.py b/test/openjd/model/v2023_09/test_job_parameters.py
index cc8bf96b..5adacfe6 100644
--- a/test/openjd/model/v2023_09/test_job_parameters.py
+++ b/test/openjd/model/v2023_09/test_job_parameters.py
@@ -26,9 +26,7 @@ class TestJobStringParameterDefinition:
             pytest.param(
                 {"name": "Foo", "type": "STRING", "default": "some value"}, id="has default"
             ),
-            pytest.param(
-                {"name": "Foo", "type": "STRING", "minLength": 1}, id="smallest min length"
-            ),
+            pytest.param({"name": "Foo", "type": "STRING", "minLength": 0}, id="minLength zero"),
             pytest.param(
                 {"name": "Foo", "type": "STRING", "maxLength": 1}, id="smallest max length"
             ),
@@ -215,7 +213,9 @@ def test_parse_success(self, data: dict[str, Any]) -> None:
                 id="allowedValues item not string",
             ),
             #
-            pytest.param({"name": "Foo", "type": "STRING", "minLength": 0}, id="0 < min"),
+            pytest.param(
+                {"name": "Foo", "type": "STRING", "minLength": -1}, id="negative minLength"
+            ),
             pytest.param({"name": "Foo", "type": "STRING", "maxLength": 0}, id="0 < max"),
             pytest.param(
                 {"name": "Foo", "type": "STRING", "minLength": 2, "maxLength": 1}, id="min > max"
@@ -495,7 +495,7 @@ class TestJobPathParameterDefinition:
             pytest.param(
                 {"name": "Foo", "type": "PATH", "default": "some value"}, id="has default"
             ),
-            pytest.param({"name": "Foo", "type": "PATH", "minLength": 1}, id="smallest min length"),
+            pytest.param({"name": "Foo", "type": "PATH", "minLength": 0}, id="minLength zero"),
             pytest.param({"name": "Foo", "type": "PATH", "maxLength": 1}, id="smallest max length"),
             pytest.param(
                 {"name": "Foo", "type": "PATH", "allowedValues": ["a"]}, id="has allowedValues"
@@ -709,7 +709,7 @@ def test_parse_success(self, data: dict[str, Any]) -> None:
                 id="allowedValues item not string",
             ),
             #
-            pytest.param({"name": "Foo", "type": "PATH", "minLength": 0}, id="0 < min"),
+            pytest.param({"name": "Foo", "type": "PATH", "minLength": -1}, id="negative minLength"),
             pytest.param({"name": "Foo", "type": "PATH", "maxLength": 0}, id="0 < max"),
             pytest.param(
                 {"name": "Foo", "type": "PATH", "minLength": 2, "maxLength": 1}, id="min > max"