diff --git a/templates/argo-tasks/README.md b/templates/argo-tasks/README.md
new file mode 100644
index 000000000..6a8e38934
--- /dev/null
+++ b/templates/argo-tasks/README.md
@@ -0,0 +1,79 @@
+# ArgoTasks Templates
+
+## argo-tasks/group - `tpl-at-group`
+
+Group inputs into outputs to be used with `withParam` to run one task per grouping
+
+### Template usage
+
+Group the output of `tile-index-validate` into groups of size 5
+
+```yaml
+- name: group
+  templateRef:
+    name: tpl-at-group
+    template: main
+
+  arguments:
+    artifacts:
+    - name: input
+        from: "{{ tasks.tile-index-validate.outputs.artifacts.files }}"
+
+    parameters:
+    - name: size
+        value: 5
+
+  depends: "tile-index-validate"
+```
+
+### Consumer usage
+
+Using `withParams` to spin up a number of tasks from
+
+```yaml
+# ...
+
+steps:
+  # consume the output of a grouper
+  - - name: consume
+      template: consume
+      arguments:
+        parameters:
+          - name: group_id
+            value: "{{item}}" # groupId eg "000", "001", "002" etc..
+
+        # All the grouped data as a folder
+        artifacts:
+          - name: group_data
+            from: "{{ steps.group.outputs.artifacts.output }}"
+
+      withParam: "{{ steps.group.outputs.parameters.output }}"
+
+# ...
+
+- name: consume
+  inputs:
+    # Id of the grouping file to consume
+    # to be used with `group_data`
+    parameters:
+    - name: group_id # "000", "001" ... etc
+
+    # grouped input data for the consumer, this will be a folder full of JSON files
+    # one file per groupId
+    artifacts:
+    - name: group_data
+      path: /tmp/input/
+
+    parameters:
+    - name: group_id # "000", "001" ... etc
+
+  script:
+    image: "019359803926.dkr.ecr.ap-southeast-2.amazonaws.com/eks:argo-tasks-latest"
+    command: [bash]
+    source: |
+      echo {{ inputs.parameters.group_id}}
+      ls -alh /tmp/input/
+
+      # for example using with a --from-file
+      # ./test-cli --from-file=/tmp/group/input/{{inputs.parameters.group_id}}.json
+```
diff --git a/templates/argo-tasks/group.yml b/templates/argo-tasks/group.yml
index 5816341bc..b66ab01c5 100644
--- a/templates/argo-tasks/group.yml
+++ b/templates/argo-tasks/group.yml
@@ -10,31 +10,48 @@ spec:
     - name: main
       inputs:
         artifacts:
+          #
+          # JSON array of things to group
+          #
+          # @example
+          # ```json
+          # ["a.json", "b.json", "c.json"]
+          # ```
           - name: input
             path: /tmp/group/input.json
-            optional: true
 
         parameters:
           - name: size
-            description: group into this number of records per group
+            description: Group into this number of records per group
 
           - name: version
-            description: container version to use
+            description: argo-task Container version to use
             default: "v2"
 
       outputs:
         parameters:
-          # Grouped output of the input
+          #
+          # JSON array of all the group ids, which correspond to a output artifact file
+          #
+          # @example
+          # ```json
+          # ["000", "001", "002", "003"]
+          # ```
+          #
+          # Workflows should use the "000" string to access the data from the output artifact folder
           - name: output
             valueFrom:
               path: /tmp/group/output.json
 
         artifacts:
-          # Grouped output of the input
+          # Grouped output of the input as one file per output groupId
+          #
+          # - /output/000.json
+          # - /output/001.json
+          # - ...
+          #
           - name: output
-            path: /tmp/group/output.json
-            archive:
-              none: {}
+            path: /tmp/group/output/
 
       container:
         image: "019359803926.dkr.ecr.ap-southeast-2.amazonaws.com/eks:argo-tasks-{{= inputs.parameters.version }}"