update usage block filter docs

Author: sacha-ichbiah

api-reference/openapi.json

@@ -4271,7 +4271,7 @@
             "required": false
           },
           {
-            "description": "Filter by block type (e.g. extract, classify, split, parse, edit, partition).",
+            "description": "Filter by block type: extract, classify, split, parse, edit, or partition. These are the primitive-kind names recorded on the execution, which differ from the workflow block type enum (a classifier block records classify). An unknown value is rejected with 422.",
             "in": "query",
             "name": "block_type",
             "schema": {
@@ -4283,7 +4283,7 @@
                   "type": "null"
                 }
               ],
-              "description": "Filter by block type (e.g. extract, classify, split, parse, edit, partition).",
+              "description": "Filter by block type: extract, classify, split, parse, edit, or partition. These are the primitive-kind names recorded on the execution, which differ from the workflow block type enum (a classifier block records classify). An unknown value is rejected with 422.",
               "title": "Block Type"
             },
             "required": false