fix: consistent font sizing in ToolCallWithResponse (#4167)

ui/desktop/src/components/MarkdownContent.tsx

@@ -46,7 +46,7 @@ const CodeBlock = ({ language, children }: { language: string; children: string
     <div className="relative group w-full">
       <button
         onClick={handleCopy}
-        className="absolute right-2 bottom-2 p-1.5 rounded-lg bg-gray-700/50 text-gray-300
+        className="absolute right-2 bottom-2 p-1.5 rounded-lg bg-gray-700/50 text-gray-300 font-sans text-sm
                  opacity-0 group-hover:opacity-100 transition-opacity duration-200
                  hover:bg-gray-600/50 hover:text-gray-100 z-10"
         title="Copy code"
@@ -68,6 +68,7 @@ const CodeBlock = ({ language, children }: { language: string; children: string
               whiteSpace: 'pre-wrap',
               wordBreak: 'break-all',
               overflowWrap: 'break-word',
+              fontFamily: 'var(--font-sans)',
             },
           }}
         >
@@ -86,7 +87,7 @@ const MarkdownCode = React.forwardRef(function MarkdownCode(
   return !inline && match ? (
     <CodeBlock language={match[1]}>{String(children).replace(/\n$/, '')}</CodeBlock>
   ) : (
-    <code ref={ref} {...props} className="break-all bg-inline-code whitespace-pre-wrap">
+    <code ref={ref} {...props} className="break-all bg-inline-code whitespace-pre-wrap font-sans">
       {children}
     </code>
   );
@@ -110,21 +111,21 @@ export default function MarkdownContent({ content, className = '' }: MarkdownCon
     <div className="w-full overflow-x-hidden">
       <ReactMarkdown
         remarkPlugins={[remarkGfm]}
-        className={`prose prose-sm text-text-default dark:prose-invert w-full max-w-full word-break
+        className={`prose prose-sm text-text-default dark:prose-invert w-full max-w-full word-break font-sans
           prose-pre:p-0 prose-pre:m-0 !p-0
-          prose-code:break-all prose-code:whitespace-pre-wrap
+          prose-code:break-all prose-code:whitespace-pre-wrap prose-code:font-sans
           prose-table:table prose-table:w-full
           prose-blockquote:text-inherit
           prose-td:border prose-td:border-border-default prose-td:p-2
           prose-th:border prose-th:border-border-default prose-th:p-2
           prose-thead:bg-background-default
-          prose-h1:text-2xl prose-h1:font-normal prose-h1:mb-5 prose-h1:mt-0
-          prose-h2:text-xl prose-h2:font-normal prose-h2:mb-4 prose-h2:mt-4
-          prose-h3:text-lg prose-h3:font-normal prose-h3:mb-3 prose-h3:mt-3
-          prose-p:mt-0 prose-p:mb-2
-          prose-ol:my-2
-          prose-ul:mt-0 prose-ul:mb-3
-          prose-li:m-0
+          prose-h1:text-2xl prose-h1:font-normal prose-h1:mb-5 prose-h1:mt-0 prose-h1:font-sans
+          prose-h2:text-xl prose-h2:font-normal prose-h2:mb-4 prose-h2:mt-4 prose-h2:font-sans
+          prose-h3:text-lg prose-h3:font-normal prose-h3:mb-3 prose-h3:mt-3 prose-h3:font-sans
+          prose-p:mt-0 prose-p:mb-2 prose-p:font-sans
+          prose-ol:my-2 prose-ol:font-sans
+          prose-ul:mt-0 prose-ul:mb-3 prose-ul:font-sans
+          prose-li:m-0 prose-li:font-sans
           ${className}`}
         components={{
           a: ({ ...props }) => <a {...props} target="_blank" rel="noopener noreferrer" />,

ui/desktop/src/components/ToolCallArguments.tsx

@@ -28,7 +28,7 @@ export function ToolCallArguments({ args }: ToolCallArgumentsProps) {
 
       if (!needsExpansion) {
         return (
-          <div className="text-xs mb-2">
+          <div className="font-sans text-sm mb-2">
             <div className="flex flex-row">
               <span className="text-textSubtle min-w-[140px]">{key}</span>
               <span className="text-textPlaceholder">{value}</span>
@@ -38,7 +38,7 @@ export function ToolCallArguments({ args }: ToolCallArgumentsProps) {
       }
 
       return (
-        <div className="text-sm mb-2">
+        <div className="font-sans text-sm mb-2">
           <div className="flex flex-row items-stretch">
             <button
               onClick={() => toggleKey(key)}
@@ -49,7 +49,10 @@ export function ToolCallArguments({ args }: ToolCallArgumentsProps) {
             <div className="w-full flex items-stretch">
               {isExpanded ? (
                 <div>
-                  <MarkdownContent content={value} className="text-sm text-textPlaceholder" />
+                  <MarkdownContent
+                    content={value}
+                    className="font-sans text-sm text-textPlaceholder"
+                  />
                 </div>
               ) : (
                 <button onClick={() => toggleKey(key)} className="text-left text-textPlaceholder">
@@ -78,7 +81,7 @@ export function ToolCallArguments({ args }: ToolCallArgumentsProps) {
 
     return (
       <div className="mb-2">
-        <div className="flex flex-row text-xs">
+        <div className="flex flex-row font-sans text-sm">
           <span className="text-textSubtle min-w-[140px]">{key}</span>
           <pre className="whitespace-pre-wrap text-textPlaceholder overflow-x-auto max-w-full">
             {content}

ui/desktop/src/components/ToolCallWithResponse.tsx

@@ -34,7 +34,7 @@ export default function ToolCallWithResponse({
     <>
       <div
         className={cn(
-          'w-full text-sm rounded-lg overflow-hidden border-borderSubtle border bg-background-muted'
+          'w-full text-sm font-sans rounded-lg overflow-hidden border-borderSubtle border bg-background-muted'
         )}
       >
         <ToolCallView
@@ -56,7 +56,7 @@ export default function ToolCallWithResponse({
                 <MCPUIResourceRenderer content={content} />
                 <div className="mt-3 p-4 py-3 border border-borderSubtle rounded-lg bg-background-muted flex items-center">
                   <FlaskConical className="mr-2" size={20} />
-                  <div className="text-sm font-medium mono">
+                  <div className="text-sm font-sans">
                     MCP UI is experimental and may change at any time.
                   </div>
                 </div>
@@ -99,7 +99,7 @@ function ToolCallExpandable({
         className="group w-full flex justify-between items-center pr-2 transition-colors rounded-none"
         variant="ghost"
       >
-        <span className="flex items-center font-mono">{label}</span>
+        <span className="flex items-center font-sans text-sm">{label}</span>
         <ChevronRight
           className={cn(
             'group-hover:opacity-100 transition-transform opacity-70',
@@ -523,7 +523,7 @@ interface ToolDetailsViewProps {
 function ToolDetailsView({ toolCall, isStartExpanded }: ToolDetailsViewProps) {
   return (
     <ToolCallExpandable
-      label={<span className="pl-4 font-medium">Tool Details</span>}
+      label={<span className="pl-4 font-sans text-sm">Tool Details</span>}
       isStartExpanded={isStartExpanded}
     >
       <div className="pr-4 pl-8">
@@ -543,7 +543,7 @@ interface ToolResultViewProps {
 function ToolResultView({ result, isStartExpanded }: ToolResultViewProps) {
   return (
     <ToolCallExpandable
-      label={<span className="pl-4 py-1 font-medium">Output</span>}
+      label={<span className="pl-4 py-1 font-sans text-sm">Output</span>}
       isStartExpanded={isStartExpanded}
     >
       <div className="pl-4 pr-4 py-4">
@@ -564,7 +564,9 @@ function ToolResultView({ result, isStartExpanded }: ToolResultViewProps) {
             }}
           />
         )}
-        {result.type === 'resource' && <pre>{JSON.stringify(result, null, 2)}</pre>}
+        {result.type === 'resource' && (
+          <pre className="font-sans text-sm">{JSON.stringify(result, null, 2)}</pre>
+        )}
       </div>
     </ToolCallExpandable>
   );
@@ -586,12 +588,18 @@ function ToolLogsView({
     if (boxRef.current) {
       boxRef.current.scrollTop = boxRef.current.scrollHeight;
     }
-  }, [logs]);
+  }, [logs.length]);
+  // normally we do not want to put .length on an array in react deps:
+  //
+  // if the objects inside the array change but length doesn't change you want updates
+  //
+  // in this case, this is array of strings which once added do not change so this cuts
+  // down on the possibility of unwanted runs
 
   return (
     <ToolCallExpandable
       label={
-        <span className="pl-4 py-1 font-medium flex items-center">
+        <span className="pl-4 py-1 font-sans text-sm flex items-center">
           <span>Logs</span>
           {working && (
             <div className="mx-2 inline-block">
@@ -612,7 +620,7 @@ function ToolLogsView({
         className={`flex flex-col items-start space-y-2 overflow-y-auto p-4 ${working ? 'max-h-[4rem]' : 'max-h-[20rem]'}`}
       >
         {logs.map((log, i) => (
-          <span key={i} className="font-mono text-sm text-textSubtle">
+          <span key={i} className="font-sans text-sm text-textSubtle">
             {log}
           </span>
         ))}
@@ -627,7 +635,7 @@ const ProgressBar = ({ progress, total, message }: Omit<Progress, 'progressToken
 
   return (
     <div className="w-full space-y-2">
-      {message && <div className="text-sm text-textSubtle">{message}</div>}
+      {message && <div className="font-sans text-sm text-textSubtle">{message}</div>}
 
       <div className="w-full bg-background-subtle rounded-full h-4 overflow-hidden relative">
         {isDeterminate ? (