diff --git a/infrahub_sdk/ctl/repository.py b/infrahub_sdk/ctl/repository.py
index 09003f6e..8f793946 100644
--- a/infrahub_sdk/ctl/repository.py
+++ b/infrahub_sdk/ctl/repository.py
@@ -71,7 +71,7 @@ async def add(
     description: str = "",
     username: str | None = None,
     password: str = "",
-    commit: str = "",
+    ref: str = "",
     read_only: bool = False,
     debug: bool = False,
     branch: str = typer.Option("main", help="Branch on which to add the repository."),  # TODO: Replace main by None
@@ -86,15 +86,24 @@ async def add(
             "name": {"value": name},
             "location": {"value": location},
             "description": {"value": description},
-            "commit": {"value": commit},
         },
     }
+    if read_only:
+        input_data["data"]["ref"] = {"value": ref}
+    else:
+        input_data["data"]["default_branch"] = {"value": ref}
 
     client = initialize_client()
 
-    credential = await client.create(kind="CorePasswordCredential", name=name, username=username, password=password)
-    await credential.save(allow_upsert=True)
-    input_data["data"]["credential"] = {"id": credential.id}
+    if username or password:
+        credential = await client.create(
+            kind="CorePasswordCredential",
+            name=name,
+            username=username,
+            password=password,
+        )
+        await credential.save(allow_upsert=True)
+        input_data["data"]["credential"] = {"id": credential.id}
 
     query = Mutation(
         mutation="CoreReadOnlyRepositoryCreate" if read_only else "CoreRepositoryCreate",
diff --git a/tests/unit/ctl/test_repository_app.py b/tests/unit/ctl/test_repository_app.py
index a7cd70f0..04d05ed4 100644
--- a/tests/unit/ctl/test_repository_app.py
+++ b/tests/unit/ctl/test_repository_app.py
@@ -29,6 +29,55 @@ def mock_client() -> mock.Mock:
 class TestInfrahubctlRepository:
     """Groups the 'infrahubctl repository' test cases."""
 
+    @requires_python_310
+    @mock.patch("infrahub_sdk.ctl.repository.initialize_client")
+    def test_repo_no_username_or_password(self, mock_init_client, mock_client) -> None:
+        """Case allow no username to be passed in and set it as None rather than blank string that fails."""
+        mock_cred = mock.AsyncMock()
+        mock_cred.id = "1234"
+        mock_client.create.return_value = mock_cred
+
+        mock_init_client.return_value = mock_client
+        output = runner.invoke(
+            app,
+            [
+                "repository",
+                "add",
+                "Gitlab",
+                "https://gitlab.com/opsmill/example-repo.git",
+            ],
+        )
+        assert output.exit_code == 0
+        mock_client.create.assert_not_called()
+        mock_cred.save.assert_not_called()
+        mock_client.execute_graphql.assert_called_once()
+        mock_client.execute_graphql.assert_called_with(
+            query="""
+mutation {
+    CoreRepositoryCreate(
+        data: {
+            name: {
+                value: "Gitlab"
+            }
+            location: {
+                value: "https://gitlab.com/opsmill/example-repo.git"
+            }
+            description: {
+                value: ""
+            }
+            default_branch: {
+                value: ""
+            }
+        }
+    ){
+        ok
+    }
+}
+""",
+            branch_name="main",
+            tracker="mutation-repository-create",
+        )
+
     @requires_python_310
     @mock.patch("infrahub_sdk.ctl.repository.initialize_client")
     def test_repo_no_username(self, mock_init_client, mock_client) -> None:
@@ -74,7 +123,7 @@ def test_repo_no_username(self, mock_init_client, mock_client) -> None:
             description: {
                 value: ""
             }
-            commit: {
+            default_branch: {
                 value: ""
             }
             credential: {
@@ -137,7 +186,7 @@ def test_repo_username(self, mock_init_client, mock_client) -> None:
             description: {
                 value: ""
             }
-            commit: {
+            default_branch: {
                 value: ""
             }
             credential: {
@@ -168,7 +217,7 @@ def test_repo_readonly_true(self, mock_init_client, mock_client) -> None:
                 "repository",
                 "add",
                 "Gitlab",
-                "https://gitlab.com/FragmentedPacket/nautobot-plugin-ansible-filters.git",
+                "https://gitlab.com/opsmill/example-repo.git",
                 "--password",
                 "mySup3rSecureP@ssw0rd",
                 "--read-only",
@@ -194,12 +243,12 @@ def test_repo_readonly_true(self, mock_init_client, mock_client) -> None:
                 value: "Gitlab"
             }
             location: {
-                value: "https://gitlab.com/FragmentedPacket/nautobot-plugin-ansible-filters.git"
+                value: "https://gitlab.com/opsmill/example-repo.git"
             }
             description: {
                 value: ""
             }
-            commit: {
+            ref: {
                 value: ""
             }
             credential: {
@@ -230,15 +279,15 @@ def test_repo_description_commit_branch(self, mock_init_client, mock_client) ->
                 "repository",
                 "add",
                 "Gitlab",
-                "https://gitlab.com/FragmentedPacket/nautobot-plugin-ansible-filters.git",
+                "https://gitlab.com/opsmill/example-repo.git",
                 "--password",
                 "mySup3rSecureP@ssw0rd",
                 "--username",
                 "opsmill",
                 "--description",
                 "This is a test description",
-                "--commit",
-                "myHashCommit",
+                "--ref",
+                "my-custom-branch",
                 "--branch",
                 "develop",
             ],
@@ -263,13 +312,13 @@ def test_repo_description_commit_branch(self, mock_init_client, mock_client) ->
                 value: "Gitlab"
             }
             location: {
-                value: "https://gitlab.com/FragmentedPacket/nautobot-plugin-ansible-filters.git"
+                value: "https://gitlab.com/opsmill/example-repo.git"
             }
             description: {
                 value: "This is a test description"
             }
-            commit: {
-                value: "myHashCommit"
+            default_branch: {
+                value: "my-custom-branch"
             }
             credential: {
                 id: "1234"