diff --git a/typespec-extension/src/code-model-builder.ts b/typespec-extension/src/code-model-builder.ts
index aaa384c217..5b7771ef13 100644
--- a/typespec-extension/src/code-model-builder.ts
+++ b/typespec-extension/src/code-model-builder.ts
@@ -1305,14 +1305,11 @@ export class CodeModelBuilder {
     });
     op.addParameter(parameter);
 
-    this.trackSchemaUsage(schema, { usage: [SchemaContext.Input] });
+    const jsonMergePatch = operationIsJsonMergePatch(sdkHttpOperation);
 
-    if (op.convenienceApi) {
-      // model/schema does not need to be Public or Internal, if it is not to be used in convenience API
-      this.trackSchemaUsage(schema, { usage: [op.internalApi ? SchemaContext.Internal : SchemaContext.Public] });
-    }
+    this.trackSchemaUsage(schema, { usage: [SchemaContext.Input] });
 
-    if (operationIsJsonMergePatch(sdkHttpOperation)) {
+    if (jsonMergePatch) {
       this.trackSchemaUsage(schema, { usage: [SchemaContext.JsonMergePatch] });
     }
     if (op.convenienceApi && operationIsMultipart(sdkHttpOperation)) {
@@ -1323,25 +1320,36 @@ export class CodeModelBuilder {
     // Implicit body parameter would result to rawHttpOperation.parameters.body.property be undefined
     // see https://typespec.io/docs/libraries/http/cheat-sheet#data-types
     const bodyParameterFlatten =
-      sdkType.kind === "model" && !rawHttpOperation.parameters.body?.property && !this.isArm();
+      schema instanceof ObjectSchema &&
+      sdkType.kind === "model" &&
+      !rawHttpOperation.parameters.body?.property &&
+      !this.isArm();
+
+    if (op.convenienceApi) {
+      // model/schema does not need to be Public or Internal, if it is not to be used in convenience API
+      if (op.internalApi) {
+        this.trackSchemaUsage(schema, { usage: [SchemaContext.Internal] });
+      } else if (!(bodyParameterFlatten && !jsonMergePatch)) {
+        // do not add Public, if going to add Spread
+        this.trackSchemaUsage(schema, { usage: [SchemaContext.Public] });
+      }
+    }
 
-    if (schema instanceof ObjectSchema && bodyParameterFlatten) {
+    if (bodyParameterFlatten) {
       // flatten body parameter
       const parameters = sdkHttpOperation.parameters;
       const bodyParameter = sdkHttpOperation.bodyParam;
-      if (!schema.language.default.name) {
-        // name the schema for documentation
-        schema.language.default.name = pascalCase(op.language.default.name) + "Request";
-      }
 
       if (!parameter.language.default.name) {
         // name the parameter for documentation
         parameter.language.default.name = "request";
       }
 
-      if (operationIsJsonMergePatch(sdkHttpOperation)) {
+      if (jsonMergePatch) {
         // skip model flatten, if "application/merge-patch+json"
-        schema.language.default.name = pascalCase(op.language.default.name) + "PatchRequest";
+        if (sdkType.isGeneratedName) {
+          schema.language.default.name = pascalCase(op.language.default.name) + "PatchRequest";
+        }
         return;
       }