chore: fix metadata

Author: kmruiz

tests/integration/tools/mongodb/read/aggregate.test.ts

@@ -20,7 +20,8 @@ describeWithMongoDB("aggregate tool", (integration) => {
         ...databaseCollectionParameters,
         {
             name: "pipeline",
-            description: "An array of aggregation stages to execute",
+            description:
+                "An array of aggregation stages to execute. $vectorSearch can only appear as the first stage of the aggregation pipeline or as the first stage of a $unionWith subpipeline.",
             type: "array",
             required: true,
         },