diff --git a/examples/Extractor-datatree.yaml b/examples/Extractor-datatree.yaml
index 57e0ada5..d4ce2e4f 100644
--- a/examples/Extractor-datatree.yaml
+++ b/examples/Extractor-datatree.yaml
@@ -17,6 +17,12 @@ usage:
       scope: meta+data
       setup: datatree
       command: datatree.open_datatree({{ file_path }})
+      format: xarray-datatree
+    - method: python
+      scope: meta+data
+      setup: datatree
+      command: datatree.open_datatree({{ file_path }}).to_dict()
+      format: xarray
 installation:
     - method: pip
       packages:
diff --git a/examples/Usage-python_setup.yaml b/examples/Usage-python_setup_format.yaml
similarity index 89%
rename from examples/Usage-python_setup.yaml
rename to examples/Usage-python_setup_format.yaml
index 958af103..6acd2c29 100644
--- a/examples/Usage-python_setup.yaml
+++ b/examples/Usage-python_setup_format.yaml
@@ -2,3 +2,4 @@
 method: python
 setup: example.extractors
 command: example.extractors.extract({{ file_path }}, type="{{ input_type }}")
+format: pandas
\ No newline at end of file
diff --git a/schemas/base.yaml b/schemas/base.yaml
index 2fb253e1..cda906d8 100644
--- a/schemas/base.yaml
+++ b/schemas/base.yaml
@@ -168,7 +168,13 @@ classes:
                 range: UsageScope
                 description: >-
                     Specification of extraction scope.
-
+            format:
+                description: >-
+                   For an `UsageType` returning an in-memory object, an additional library
+                   installed in the calling environment may be needed to understand the
+                   format of the returned object. For instance, if a `pd.DataFrame` is
+                   returned by the `Usage`, set `format` to `pandas` to indicate this
+                   requirement.
 
     Installation:
         description: >-