fix(frontend): strip and parse the <current_uploads> upload context tag (#4402)

* fix(frontend): strip and parse the <current_uploads> upload context tag

#4174 renamed the upload context block that UploadsMiddleware prepends to
the user message from <uploaded_files> to <current_uploads>, but the
frontend tag vocabulary was not updated, so the raw block (file list plus
usage guidance) rendered inside the user's chat bubble and the file-chip
content fallback stopped matching. Add the new tag to
stripUploadedFilesTag, INTERNAL_MARKER_TAGS (covers export and streamdown
preprocessing), parseUploadedFiles, and the chip fallback detection.
<uploaded_files> stays supported for history and IM-channel messages.

* fix(frontend): parse upload-context sizes to bytes for the file chip

parseUploadedFiles stored the raw leading number of the human-readable
size (e.g. parseInt("177.6 KB") -> 177) into FileInMessage.size, which
is documented as bytes. On the content-fallback chip path (history/IM
messages without additional_kwargs.files) formatBytes then rendered a
177.6 KB file as "0.2 KB".

Convert the backend's "<n> KB" / "<n> MB" form back to bytes so the chip
re-renders at the original magnitude; update the parse tests to assert
byte values.

frontend/src/components/workspace/messages/message-list-item.tsx

@@ -319,8 +319,11 @@ function MessageContent_({
   const files = useMemo(() => {
     const files = message.additional_kwargs?.files;
     if (!Array.isArray(files) || files.length === 0) {
-      if (rawContent.includes("<uploaded_files>")) {
-        // If the content contains the <uploaded_files> tag, we return the parsed files from the content for backward compatibility.
+      if (
+        rawContent.includes("<current_uploads>") ||
+        rawContent.includes("<uploaded_files>")
+      ) {
+        // If the content contains an upload context tag, we return the parsed files from the content for backward compatibility.
         return parseUploadedFiles(rawContent);
       }
       return null;

frontend/src/core/messages/utils.ts

@@ -596,7 +596,10 @@ export interface FileInMessage {
  */
 export function stripUploadedFilesTag(content: string): string {
   return content
-    .replace(/<(uploaded_files|slash_skill_activation)>[\s\S]*?<\/\1>/g, "")
+    .replace(
+      /<(current_uploads|uploaded_files|slash_skill_activation)>[\s\S]*?<\/\1>/g,
+      "",
+    )
     .trim();
 }
 
@@ -606,7 +609,8 @@ export function stripUploadedFilesTag(content: string): string {
  *
  * These markers are *not* user copy — they come from:
  *
- * - ``UploadsMiddleware`` → ``<uploaded_files>``
+ * - ``UploadsMiddleware`` → ``<current_uploads>`` (``<uploaded_files>``
+ *   before #4174; still emitted by IM channels and present in history)
  * - ``SkillActivationMiddleware`` → ``<slash_skill_activation>``
  * - ``DynamicContextMiddleware`` → ``<system-reminder>`` (carrying
  *   ``<memory>`` / ``<current_date>`` inside)
@@ -620,6 +624,7 @@ export function stripUploadedFilesTag(content: string): string {
  * its ``hide_from_ui`` flag set.
  */
 export const INTERNAL_MARKER_TAGS = [
+  "current_uploads",
   "uploaded_files",
   "slash_skill_activation",
   "system-reminder",
@@ -646,9 +651,32 @@ export function stripInternalMarkers(content: string): string {
   return content.replace(INTERNAL_MARKER_RE, "").trim();
 }
 
+// The upload context block renders sizes as human-readable strings
+// (uploads_middleware.py::_format_file_entry emits "<n> KB" / "<n> MB",
+// mirroring formatBytes). Convert them back to bytes so the parsed
+// FileInMessage.size honours its bytes contract and chips re-render at the
+// original magnitude instead of e.g. treating "177.6 KB" as 177 bytes.
+function parseHumanReadableSize(raw: string): number {
+  const match = /([\d.]+)\s*(B|KB|MB|GB|TB)?/i.exec(raw.trim());
+  if (!match) return 0;
+  const value = parseFloat(match[1] ?? "");
+  if (!Number.isFinite(value)) return 0;
+  const multipliers: Record<string, number> = {
+    B: 1,
+    KB: 1024,
+    MB: 1024 ** 2,
+    GB: 1024 ** 3,
+    TB: 1024 ** 4,
+  };
+  const unit = (match[2] ?? "B").toUpperCase();
+  return Math.round(value * (multipliers[unit] ?? 1));
+}
+
 export function parseUploadedFiles(content: string): FileInMessage[] {
-  // Match <uploaded_files>...</uploaded_files> tag
-  const uploadedFilesRegex = /<uploaded_files>([\s\S]*?)<\/uploaded_files>/;
+  // Match the upload context block; the tag name depends on backend version
+  // (<current_uploads> since #4174, <uploaded_files> before / on IM paths).
+  const uploadedFilesRegex =
+    /<(current_uploads|uploaded_files)>([\s\S]*?)<\/\1>/;
   // eslint-disable-next-line @typescript-eslint/prefer-regexp-exec
   const match = content.match(uploadedFilesRegex);
 
@@ -656,7 +684,7 @@ export function parseUploadedFiles(content: string): FileInMessage[] {
     return [];
   }
 
-  const uploadedFilesContent = match[1];
+  const uploadedFilesContent = match[2];
 
   // Check if it's "No files have been uploaded yet."
   if (uploadedFilesContent?.includes("No files have been uploaded yet.")) {
@@ -677,7 +705,7 @@ export function parseUploadedFiles(content: string): FileInMessage[] {
   while ((fileMatch = fileRegex.exec(uploadedFilesContent ?? "")) !== null) {
     files.push({
       filename: fileMatch[1].trim(),
-      size: parseInt(fileMatch[2].trim(), 10) ?? 0,
+      size: parseHumanReadableSize(fileMatch[2]),
       path: fileMatch[3].trim(),
     });
   }

frontend/tests/unit/core/messages/utils.test.ts

@@ -14,6 +14,8 @@ import {
   hasContent,
   hasReasoning,
   isAssistantMessageGroupStreaming,
+  parseUploadedFiles,
+  stripInternalMarkers,
   stripUploadedFilesTag,
 } from "@/core/messages/utils";
 
@@ -307,6 +309,47 @@ describe("human message internal context stripping", () => {
     expect(getMessageCopyData(message)).toBe("Summarize this paper");
   });
 
+  test("strips current_uploads context from copy data", () => {
+    // Mirrors the block UploadsMiddleware emits since #4174, including the
+    // trailing usage-guidance lines.
+    const message = {
+      id: "human-with-current-uploads",
+      type: "human",
+      content:
+        "<current_uploads>\nThe following files were uploaded in this message:\n\n- paper.docx (177.6 KB)\n  Path: /mnt/user-data/uploads/paper.docx\n\nTo work with these files:\n- Use `grep` to search for keywords\n  (e.g. `grep(pattern='revenue', path='/mnt/user-data/uploads/')`).\n</current_uploads>\n\nMake a slide deck from this",
+    } as Message;
+
+    expect(getMessageCopyData(message)).toBe("Make a slide deck from this");
+  });
+
+  test("parses uploaded files from a current_uploads block", () => {
+    const content =
+      "<current_uploads>\nThe following files were uploaded in this message:\n\n- paper.docx (177.6 KB)\n  Path: /mnt/user-data/uploads/paper.docx\n  Document outline (use `read_file` with line ranges to read sections):\n    L1: Introduction\n- data.xlsx (12.0 KB)\n  Path: /mnt/user-data/uploads/data.xlsx\n</current_uploads>\n\nSummarize";
+
+    // size is bytes (FileInMessage contract): the block's "177.6 KB" /
+    // "12.0 KB" are converted back from the human-readable form the backend
+    // emits, so formatBytes re-renders them at the original magnitude.
+    expect(parseUploadedFiles(content)).toEqual([
+      {
+        filename: "paper.docx",
+        size: Math.round(177.6 * 1024), // 181862
+        path: "/mnt/user-data/uploads/paper.docx",
+      },
+      {
+        filename: "data.xlsx",
+        size: 12 * 1024, // 12288
+        path: "/mnt/user-data/uploads/data.xlsx",
+      },
+    ]);
+  });
+
+  test("stripInternalMarkers removes current_uploads blocks on export", () => {
+    const content =
+      "<current_uploads>\n- paper.docx (177.6 KB)\n  Path: /mnt/user-data/uploads/paper.docx\n</current_uploads>\n\nExport me";
+
+    expect(stripInternalMarkers(content)).toBe("Export me");
+  });
+
   test("strips slash skill activation context from display content", () => {
     const content =
       "<slash_skill_activation>\n<skill_content># Secret SKILL.md</skill_content>\n</slash_skill_activation>\nreal user task";