diff --git a/tests/README.md b/tests/README.md
index 2d18fddc..5d166983 100644
--- a/tests/README.md
+++ b/tests/README.md
@@ -8,7 +8,6 @@ This folder contains test cases for the openEO processes.
 - [x] add
 - [ ] add_dimension
 - [ ] aggregate_spatial
-- [ ] aggregate_spatial_window
 - [ ] aggregate_temporal
 - [ ] aggregate_temporal_period
 - [x] all
@@ -19,7 +18,6 @@ This folder contains test cases for the openEO processes.
 - [ ] apply_dimension
 - [ ] apply_kernel
 - [ ] apply_neighborhood
-- [ ] apply_polygon
 - [x] arccos - <https://github.com/Open-EO/openeo-processes/pull/476>
 - [x] arcosh - <https://github.com/Open-EO/openeo-processes/pull/476>
 - [x] arcsin - <https://github.com/Open-EO/openeo-processes/pull/476>
@@ -30,14 +28,12 @@ This folder contains test cases for the openEO processes.
 - [ ] array_concat
 - [ ] array_contains
 - [ ] array_create
-- [ ] array_create_labeled
 - [ ] array_element
 - [ ] array_filter
 - [ ] array_find
-- [ ] array_find_label
 - [ ] array_interpolate_linear
 - [ ] array_labels
-- [ ] array_modify
+- [x] array_modify (experimental) - could use some more tests
 - [x] arsinh
 - [x] artanh - <https://github.com/Open-EO/openeo-processes/pull/476>
 - [ ] between
@@ -48,14 +44,14 @@ This folder contains test cases for the openEO processes.
 - [x] cos - <https://github.com/Open-EO/openeo-processes/pull/476>
 - [x] cosh - <https://github.com/Open-EO/openeo-processes/pull/476>
 - [ ] count
+- [x] cummax (experimental) - could use some more tests
+- [x] cummin (experimental) - could use some more tests
+- [x] cumproduct (experimental) - could use some more tests
+- [x] cumsum (experimental) - could use some more tests
 - [ ] create_data_cube
-- [ ] cummax
-- [ ] cummin
-- [ ] cumproduct
-- [ ] cumsum
-- [ ] date_between
-- [ ] date_difference
-- [ ] date_shift
+- [ ] date_between (experimental) - could use some more tests
+- [ ] date_difference (experimental) - could use some more tests
+- [ ] date_shift (experimental) - could use some more tests
 - [ ] dimension_labels
 - [x] divide - <https://github.com/Open-EO/openeo-processes/pull/473>
 - [ ] drop_dimension
@@ -65,27 +61,19 @@ This folder contains test cases for the openEO processes.
 - [ ] extrema
 - [ ] filter_bands
 - [ ] filter_bbox
-- [ ] filter_labels
 - [ ] filter_spatial
 - [ ] filter_temporal
-- [ ] filter_vector
 - [ ] first
-- [ ] flatten_dimensions
 - [x] floor
 - [ ] gt
 - [ ] gte
-- [ ] if
+- [x] if
 - [x] int
-- [ ] is_infinite
+- [x] is_infinite (experimental)
 - [x] is_nan
-- [ ] is_valid
 - [ ] last
 - [ ] linear_scale_range
 - [x] ln - <https://github.com/Open-EO/openeo-processes/pull/473>
-- [ ] load_geojson
-- [ ] load_stac
-- [ ] load_uploaded_files
-- [ ] load_url
 - [x] log - <https://github.com/Open-EO/openeo-processes/pull/473>
 - [ ] lt
 - [ ] lte
@@ -98,7 +86,7 @@ This folder contains test cases for the openEO processes.
 - [ ] min
 - [x] mod - <https://github.com/Open-EO/openeo-processes/pull/473>
 - [ ] multiply
-- [x] nan
+- [x] nan (experimental)
 - [ ] ndvi
 - [ ] neq
 - [ ] normalized_difference
@@ -111,7 +99,6 @@ This folder contains test cases for the openEO processes.
 - [ ] quantiles
 - [ ] rearrange
 - [ ] reduce_dimension
-- [ ] reduce_spatial
 - [ ] rename_dimension
 - [ ] rename_labels
 - [ ] resample_cube_spatial
@@ -133,11 +120,7 @@ This folder contains test cases for the openEO processes.
 - [x] text_contains
 - [x] text_ends
 - [ ] trim_cube
-- [ ] unflatten_dimension
 - [ ] variance
-- [ ] vector_buffer
-- [ ] vector_reproject
-- [ ] vector_to_regular_points
 - [x] xor
 
 ## Incomplete processes
@@ -150,20 +133,38 @@ The following processes have no test cases as the results heavily depend on the
 or need an external services to be available for testing (e.g. loading files from the user workspace or a UDF server).
 We don't expect that we can provide meaningful test cases for these processes.
 
-- [ ] ard_normalized_radar_backscatter
-- [ ] ard_surface_reflectance
-- [ ] atmospheric_correction
-- [ ] cloud_detection
-- [ ] fit_curve
-- [ ] inspect
+- [ ] ard_normalized_radar_backscatter (experimental)
+- [ ] ard_surface_reflectance (experimental)
+- [ ] atmospheric_correction (experimental)
+- [ ] cloud_detection (experimental)
+- [ ] fit_curve (experimental)
+- [ ] inspect (experimental)
 - [ ] load_collection
-- [ ] load_uploaded_files
-- [ ] predict_curve
+- [ ] load_stac (experimental)
+- [ ] load_uploaded_files (experimental)
+- [ ] predict_curve (experimental)
 - [ ] run_udf
-- [ ] run_udf_externally
-- [ ] sar_backscatter
+- [ ] run_udf_externally (experimental)
+- [ ] sar_backscatter (experimental)
 - [ ] save_result
-- [ ] vector_to_random_points
+- [ ] vector_to_random_points (experimental)
+
+The following processes are in proposal state (i.e. experimental) and may be added later:
+
+- [ ] aggregate_spatial_window (experimental)
+- [ ] apply_polygon (experimental)
+- [ ] array_create_labeled (experimental)
+- [ ] array_find_label (experimental)
+- [ ] filter_labels (experimental)
+- [ ] filter_vector (experimental)
+- [ ] flatten_dimensions (experimental)
+- [ ] load_geojson (experimental)
+- [ ] load_url (experimental)
+- [ ] reduce_spatial (experimental)
+- [ ] unflatten_dimension (experimental)
+- [ ] vector_buffer (experimental)
+- [ ] vector_reproject (experimental)
+- [ ] vector_to_regular_points (experimental)
 
 ## Assumptions
 
@@ -235,6 +236,45 @@ Arguments and return values can point to external files, e.g.
 }
 ```
 
+There are a couple of data types that can't be represented in JSON5 and will be provided as an object instead.
+
+**Labeled arrays:**
+```json
+{
+  "type": "labeled-array",
+  "data": [
+    {
+      "key": "B01",
+      "value": 1.23
+    },
+    {
+      "key": "B02",
+      "value": 0.98
+    }
+    // ...
+  ]
+}
+```
+
+**Data Cube Metadata:**
+```json
+{
+  "type": "datacube",
+  "data": {
+    // uses the STAC datacube extension
+    "bands": {
+        "type": "bands",
+        "values": [
+          "B01",
+          "B02",
+          "Bo3"
+        ]
+    }
+    // ...
+  }
+}
+```
+
 ### Assets
 
 Additional assets will be provided for the test cases.
diff --git a/tests/aggregate_spatial_window.json5 b/tests/aggregate_spatial_window.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/aggregate_spatial_window.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/and.json5 b/tests/and.json5
index 6e2c8eb8..738239f1 100644
--- a/tests/and.json5
+++ b/tests/and.json5
@@ -14,6 +14,20 @@
       },
       "returns": false
     },
+    {
+      "arguments": {
+        "x": true,
+        "y": null
+      },
+      "returns": null
+    },
+    {
+      "arguments": {
+        "x": false,
+        "y": true
+      },
+      "returns": false
+    },
     {
       "arguments": {
         "x": false,
@@ -30,7 +44,21 @@
     },
     {
       "arguments": {
-        "x": true,
+        "x": null,
+        "y": true
+      },
+      "returns": null
+    },
+    {
+      "arguments": {
+        "x": null,
+        "y": false
+      },
+      "returns": false
+    },
+    {
+      "arguments": {
+        "x": null,
         "y": null
       },
       "returns": null
diff --git a/tests/apply_polygon.json5 b/tests/apply_polygon.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/apply_polygon.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/array_create_labeled.json5 b/tests/array_create_labeled.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/array_create_labeled.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/array_find_label.json5 b/tests/array_find_label.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/array_find_label.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/filter_labels.json5 b/tests/filter_labels.json5
deleted file mode 100644
index f0460bb1..00000000
--- a/tests/filter_labels.json5
+++ /dev/null
@@ -1,28 +0,0 @@
-{
-  "tests": [
-    {
-      // Filters the data cube to only contain data from platform Sentinel-2A. This example assumes that the data cube has a dimension `platform` so that computations can distinguish between Sentinel-2A and Sentinel-2B data.
-      "arguments": {
-        "data": {
-          "from_parameter": "sentinel2_data"
-        },
-        "condition": {
-          "process_graph": {
-            "eq": {
-              "process_id": "eq",
-              "arguments": {
-                "x": {
-                  "from_parameter": "value"
-                },
-                "y": "Sentinel-2A",
-                "case_sensitive": false
-              },
-              "result": true
-            }
-          }
-        },
-        "dimension": "platform"
-      }
-    }
-  ]
-}
\ No newline at end of file
diff --git a/tests/filter_vector.json5 b/tests/filter_vector.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/filter_vector.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/flatten_dimensions.json5 b/tests/flatten_dimensions.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/flatten_dimensions.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/is_infinite.json5 b/tests/is_infinite.json5
index 2c6ac1cf..881f0f34 100644
--- a/tests/is_infinite.json5
+++ b/tests/is_infinite.json5
@@ -20,7 +20,13 @@
     },
     {
       "arguments": {
-        "x": -123456789.0
+        "x": 4294967296
+      },
+      "returns": false
+    },
+    {
+      "arguments": {
+        "x": -4294967296.0
       },
       "returns": false
     },
@@ -102,6 +108,24 @@
       },
       "returns": false
     },
+    {
+      "arguments": {
+        "x": "+infinity"
+      },
+      "returns": false
+    },
+    {
+      "arguments": {
+        "x": "+Infinity"
+      },
+      "returns": false
+    },
+    {
+      "arguments": {
+        "x": "+inf"
+      },
+      "returns": false
+    },
     {
       "arguments": {
         "x": null
diff --git a/tests/is_nodata.json5 b/tests/is_nodata.json5
index dd81695c..6ba64844 100644
--- a/tests/is_nodata.json5
+++ b/tests/is_nodata.json5
@@ -12,7 +12,9 @@
       "arguments": {
         "x": 1
       },
-      "returns": false
+      "returns": false,
+      // Optional to avoid an error in case the no-data value is 1
+      "optional": true
     },
     {
       "arguments": {
diff --git a/tests/load_geojson.json5 b/tests/load_geojson.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/load_geojson.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/load_stac.json5 b/tests/load_stac.json5
deleted file mode 100644
index 0e44535d..00000000
--- a/tests/load_stac.json5
+++ /dev/null
@@ -1,58 +0,0 @@
-{
-  "tests": [
-    {
-      "title": "Load from a static STAC / batch job result",
-      "arguments": {
-        "url": "https://example.com/api/v1.0/jobs/123/results"
-      }
-    },
-    {
-      "title": "Load from a STAC API",
-      "arguments": {
-        "url": "https://example.com/collections/SENTINEL2",
-        "spatial_extent": {
-          "west": 16.1,
-          "east": 16.6,
-          "north": 48.6,
-          "south": 47.2
-        },
-        "temporal_extent": [
-          "2018-01-01",
-          "2019-01-01"
-        ],
-        "properties": {
-          "eo:cloud_cover": {
-            "process_graph": {
-              "cc": {
-                "process_id": "between",
-                "arguments": {
-                  "x": {
-                    "from_parameter": "value"
-                  },
-                  "min": 0,
-                  "max": 50
-                },
-                "result": true
-              }
-            }
-          },
-          "platform": {
-            "process_graph": {
-              "pf": {
-                "process_id": "eq",
-                "arguments": {
-                  "x": {
-                    "from_parameter": "value"
-                  },
-                  "y": "Sentinel-2B",
-                  "case_sensitive": false
-                },
-                "result": true
-              }
-            }
-          }
-        }
-      }
-    }
-  ]
-}
\ No newline at end of file
diff --git a/tests/load_uploaded_files.json5 b/tests/load_uploaded_files.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/load_uploaded_files.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/load_url.json5 b/tests/load_url.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/load_url.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/or.json5 b/tests/or.json5
index 4a51e098..2622a868 100644
--- a/tests/or.json5
+++ b/tests/or.json5
@@ -9,10 +9,10 @@
     },
     {
       "arguments": {
-        "x": false,
+        "x": true,
         "y": false
       },
-      "returns": false
+      "returns": true
     },
     {
       "arguments": {
@@ -23,7 +23,7 @@
     },
     {
       "arguments": {
-        "x": null,
+        "x": false,
         "y": true
       },
       "returns": true
@@ -31,6 +31,34 @@
     {
       "arguments": {
         "x": false,
+        "y": false
+      },
+      "returns": false
+    },
+    {
+      "arguments": {
+        "x": false,
+        "y": null
+      },
+      "returns": null
+    },
+    {
+      "arguments": {
+        "x": null,
+        "y": true
+      },
+      "returns": true
+    },
+    {
+      "arguments": {
+        "x": null,
+        "y": false
+      },
+      "returns": null
+    },
+    {
+      "arguments": {
+        "x": null,
         "y": null
       },
       "returns": null
diff --git a/tests/reduce_spatial.json5 b/tests/reduce_spatial.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/reduce_spatial.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/unflatten_dimension.json5 b/tests/unflatten_dimension.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/unflatten_dimension.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/vector_buffer.json5 b/tests/vector_buffer.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/vector_buffer.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/vector_reproject.json5 b/tests/vector_reproject.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/vector_reproject.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/vector_to_regular_points.json5 b/tests/vector_to_regular_points.json5
deleted file mode 100644
index 308e1aa1..00000000
--- a/tests/vector_to_regular_points.json5
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "tests": []
-}
\ No newline at end of file
diff --git a/tests/xor.json5 b/tests/xor.json5
index 0cb12326..88788b40 100644
--- a/tests/xor.json5
+++ b/tests/xor.json5
@@ -9,28 +9,56 @@
     },
     {
       "arguments": {
-        "x": false,
+        "x": true,
         "y": false
       },
-      "returns": false
+      "returns": true
     },
     {
       "arguments": {
         "x": true,
-        "y": false
+        "y": null
+      },
+      "returns": null
+    },
+    {
+      "arguments": {
+        "x": false,
+        "y": true
       },
       "returns": true
     },
     {
       "arguments": {
-        "x": true,
+        "x": false,
+        "y": false
+      },
+      "returns": false
+    },
+    {
+      "arguments": {
+        "x": false,
         "y": null
       },
       "returns": null
     },
     {
       "arguments": {
-        "x": false,
+        "x": null,
+        "y": true
+      },
+      "returns": null
+    },
+    {
+      "arguments": {
+        "x": null,
+        "y": false
+      },
+      "returns": null
+    },
+    {
+      "arguments": {
+        "x": null,
         "y": null
       },
       "returns": null