🔧 fix: Await MCP Instructions and Filter Malformed Tool Calls (#10485)

* fix: Await MCP instructions formatting in AgentClient

* fix: don't render or aggregate malformed tool calls

* fix: implement filter for malformed tool call content parts and add tests

packages/api/src/utils/content.ts

@@ -0,0 +1,46 @@
+import { ContentTypes } from 'librechat-data-provider';
+import type { TMessageContentParts } from 'librechat-data-provider';
+
+/**
+ * Filters out malformed tool call content parts that don't have the required tool_call property.
+ * This handles edge cases where tool_call content parts may be created with only a type property
+ * but missing the actual tool_call data.
+ *
+ * @param contentParts - Array of content parts to filter
+ * @returns Filtered array with malformed tool calls removed
+ *
+ * @example
+ * // Removes malformed tool_call without the tool_call property
+ * const parts = [
+ *   { type: 'tool_call', tool_call: { id: '123', name: 'test' } }, // valid - kept
+ *   { type: 'tool_call' }, // invalid - filtered out
+ *   { type: 'text', text: 'Hello' }, // valid - kept (other types pass through)
+ * ];
+ * const filtered = filterMalformedContentParts(parts);
+ * // Returns all parts except the malformed tool_call
+ */
+export function filterMalformedContentParts(
+  contentParts: TMessageContentParts[],
+): TMessageContentParts[];
+export function filterMalformedContentParts<T>(contentParts: T): T;
+export function filterMalformedContentParts<T>(
+  contentParts: T | TMessageContentParts[],
+): T | TMessageContentParts[] {
+  if (!Array.isArray(contentParts)) {
+    return contentParts;
+  }
+
+  return contentParts.filter((part) => {
+    if (!part || typeof part !== 'object') {
+      return false;
+    }
+
+    const { type } = part;
+
+    if (type === ContentTypes.TOOL_CALL) {
+      return 'tool_call' in part && part.tool_call != null && typeof part.tool_call === 'object';
+    }
+
+    return true;
+  });
+}