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diff --git a/src/mongo/db/query/query_stats/agg_key.h b/src/mongo/db/query/query_stats/agg_key.h
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+/**
+ *    Copyright (C) 2023-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include <cstdint>
+#include <utility>
+
+#include <absl/container/node_hash_map.h>
+#include <boost/move/utility_core.hpp>
+#include <boost/none.hpp>
+#include <boost/optional/optional.hpp>
+#include <boost/smart_ptr/intrusive_ptr.hpp>
+
+#include "mongo/base/string_data.h"
+#include "mongo/bson/bsonobj.h"
+#include "mongo/bson/bsonobjbuilder.h"
+#include "mongo/db/collection_type.h"
+#include "mongo/db/namespace_string.h"
+#include "mongo/db/operation_context.h"
+#include "mongo/db/pipeline/aggregate_command_gen.h"
+#include "mongo/db/pipeline/expression_context.h"
+#include "mongo/db/pipeline/pipeline.h"
+#include "mongo/db/pipeline/variables.h"
+#include "mongo/db/query/explain_options.h"
+#include "mongo/db/query/query_shape/query_shape.h"
+#include "mongo/db/query/query_stats/key.h"
+
+namespace mongo::query_stats {
+
+/**
+ * Struct representing the aggregate command's unique arguments which should be included in the
+ * query stats key.
+ */
+struct AggCmdComponents : public SpecificKeyComponents {
+    static constexpr StringData kOtherNssFieldName = "otherNss"_sd;
+
+    AggCmdComponents(const AggregateCommandRequest&,
+                     stdx::unordered_set<NamespaceString> involvedNamespaces);
+
+    void HashValue(absl::HashState state) const final;
+
+    void appendTo(BSONObjBuilder& bob, const SerializationOptions& opts) const;
+
+    size_t size() const;
+
+    stdx::unordered_set<NamespaceString> involvedNamespaces;
+    bool _bypassDocumentValidation;
+    const boost::optional<mongo::ExplainOptions::Verbosity> _verbosity;
+
+    // This anonymous struct represents the presence of the member variables as C++ bit fields.
+    // In doing so, each of these boolean values takes up 1 bit instead of 1 byte.
+    struct HasField {
+        HasField() : batchSize(false), bypassDocumentValidation(false), explain(false) {}
+        bool batchSize : 1;
+        bool bypassDocumentValidation : 1;
+        bool explain : 1;
+        bool passthroughToShard : 1;
+    } _hasField;
+};
+
+/**
+ * Handles shapification for AggregateCommandRequests. Requires a pre-parsed pipeline in order to
+ * avoid parsing the raw pipeline multiple times, but users should be sure to provide a
+ * non-optimized pipeline.
+ */
+class AggKey final : public Key {
+public:
+    AggKey(AggregateCommandRequest request,
+           const Pipeline& pipeline,
+           const boost::intrusive_ptr<ExpressionContext>& expCtx,
+           stdx::unordered_set<NamespaceString> involvedNamespaces,
+           const NamespaceString& origNss,
+           query_shape::CollectionType collectionType = query_shape::CollectionType::kUnknown);
+
+    const SpecificKeyComponents& specificComponents() const final {
+        return _components;
+    }
+
+    // The default implementation of hashing for smart pointers is not a good one for our purposes.
+    // Here we overload them to actually take the hash of the object, rather than hashing the
+    // pointer itself.
+    template <typename H>
+    friend H AbslHashValue(H h, const std::unique_ptr<const AggKey>& key) {
+        return H::combine(std::move(h), *key);
+    }
+    template <typename H>
+    friend H AbslHashValue(H h, const std::shared_ptr<const AggKey>& key) {
+        return H::combine(std::move(h), *key);
+    }
+
+
+protected:
+    void appendCommandSpecificComponents(BSONObjBuilder& bob,
+                                         const SerializationOptions& opts) const final override;
+
+private:
+    const AggCmdComponents _components;
+};
+static_assert(
+    sizeof(AggKey) == sizeof(Key) + sizeof(AggCmdComponents),
+    "If the class' members have changed, this assert may need to be updated with a new value.");
+}  // namespace mongo::query_stats