fix: tool call UI cleanup (#515)

Co-authored-by: Letta <noreply@letta.com>

src/cli/components/AdvancedDiffRenderer.tsx

@@ -401,7 +401,7 @@ export function AdvancedDiffRenderer(
                 <Text dimColor>⎿</Text>
               </Text>
             </Box>
-            <Box flexGrow={1}>
+            <Box flexGrow={1} width={Math.max(0, columns - noChangesGutter)}>
               <Text wrap="wrap">{header}</Text>
             </Box>
           </Box>
@@ -410,7 +410,7 @@ export function AdvancedDiffRenderer(
           <Box width={noChangesGutter} flexShrink={0}>
             <Text>{"    "}</Text>
           </Box>
-          <Box flexGrow={1}>
+          <Box flexGrow={1} width={Math.max(0, columns - noChangesGutter)}>
             <Text dimColor>
               No changes to <Text bold>{relative}</Text> (file content
               identical)
@@ -435,7 +435,7 @@ export function AdvancedDiffRenderer(
                 <Text dimColor>⎿</Text>
               </Text>
             </Box>
-            <Box flexGrow={1}>
+            <Box flexGrow={1} width={Math.max(0, columns - toolResultGutter)}>
               <Text wrap="wrap">{header}</Text>
             </Box>
           </Box>
@@ -443,7 +443,7 @@ export function AdvancedDiffRenderer(
             <Box width={toolResultGutter} flexShrink={0}>
               <Text>{"    "}</Text>
             </Box>
-            <Box flexGrow={1}>
+            <Box flexGrow={1} width={Math.max(0, columns - toolResultGutter)}>
               <Text
                 dimColor
               >{`Showing ~${ADV_DIFF_CONTEXT_LINES} context line${ADV_DIFF_CONTEXT_LINES === 1 ? "" : "s"}`}</Text>

src/cli/components/ToolCallMessageRich.tsx

@@ -69,10 +69,12 @@ export const ToolCallMessage = memo(
     line,
     precomputedDiffs,
     lastPlanFilePath,
+    isStreaming,
   }: {
     line: ToolCallLine;
     precomputedDiffs?: Map<string, AdvancedDiffSuccess>;
     lastPlanFilePath?: string | null;
+    isStreaming?: boolean;
   }) => {
     const columns = useTerminalWidth();
 
@@ -124,14 +126,36 @@ export const ToolCallMessage = memo(
       }
     }
 
-    // Format arguments for display using the old formatting logic
-    // Pass rawName to enable special formatting for file tools
-    const formatted = formatArgsDisplay(argsText, rawName);
-    // Hide args for question tool (shown in result instead)
-    const args = isQuestionTool(rawName) ? "" : `(${formatted.display})`;
-
     const rightWidth = Math.max(0, columns - 2); // gutter is 2 cols
 
+    // Determine args display:
+    // - Question tool: hide args (shown in result instead)
+    // - Still streaming + phase "ready": args may be incomplete, show ellipsis
+    // - Phase "running"/"finished" or stream done: args complete, show formatted
+    let args = "";
+    if (!isQuestionTool(rawName)) {
+      // Args are complete once running, finished, or stream is done
+      const argsComplete =
+        line.phase === "running" || line.phase === "finished" || !isStreaming;
+
+      if (!argsComplete) {
+        args = "(…)";
+      } else {
+        const formatted = formatArgsDisplay(argsText, rawName);
+        // Normalize newlines to spaces to prevent forced line breaks
+        const normalizedDisplay = formatted.display.replace(/\n/g, " ");
+        // For max 2 lines: boxWidth * 2, minus parens (2) and margin (2)
+        const argsBoxWidth = rightWidth - displayName.length;
+        const maxArgsChars = Math.max(0, argsBoxWidth * 2 - 4);
+
+        const needsTruncation = normalizedDisplay.length > maxArgsChars;
+        const truncatedDisplay = needsTruncation
+          ? `${normalizedDisplay.slice(0, maxArgsChars - 1)}…`
+          : normalizedDisplay;
+        args = `(${truncatedDisplay})`;
+      }
+    }
+
     // If name exceeds available width, fall back to simple wrapped rendering
     const fallback = displayName.length >= rightWidth;