diff --git a/src/components/FunctionDefinition.js b/src/components/FunctionDefinition.js
index 610cf3b7d..19b27bc8f 100644
--- a/src/components/FunctionDefinition.js
+++ b/src/components/FunctionDefinition.js
@@ -27,8 +27,8 @@ const FunctionDefinition = ({ params, returnValue }) => {
       </span>
       {params.map((param, i) => (
         <div key={i} className={styles.param}>
-          <span className={styles.paramName}>{param.name}: </span>
-          <span className={styles.type}>{param.type} </span>
+          {param.name}: <span className={styles.type}>{param.type} </span>
+          {i !== params.length - 1 && ','}
           <Markdown
             source={param.description}
             renderers={{
diff --git a/src/components/FunctionDefinition.module.scss b/src/components/FunctionDefinition.module.scss
index bf7751adc..719e24fb8 100644
--- a/src/components/FunctionDefinition.module.scss
+++ b/src/components/FunctionDefinition.module.scss
@@ -9,11 +9,8 @@
 }
 
 .param {
-  margin-left: 1rem;
-}
-
-.paramName {
   color: var(--color-neutrals-700);
+  margin-left: 1rem;
 }
 
 .paramDescription {
diff --git a/src/utils/propTypeInfo.js b/src/utils/propTypeInfo.js
index 0bac6ad66..31a6f34c4 100644
--- a/src/utils/propTypeInfo.js
+++ b/src/utils/propTypeInfo.js
@@ -98,8 +98,8 @@ export const getTypeMeta = (name, propType, { component }) => {
   switch (getRawTypeName(propType)) {
     case 'func':
       return {
-        returnValue: propTypeDocs.tags?.returnValue ?? { type: 'undefined' },
-        params: propTypeDocs.tags?.param ?? [],
+        returnValue: propTypeDocs?.tags?.returnValue ?? { type: 'undefined' },
+        params: propTypeDocs?.tags?.param ?? [],
       };
     case 'shape': {
       const [shape] = getArgs(propType);