Image uploads are not supported for file search tool resourc

Error message

Image uploads are not supported for file search tool resources

What it means

Thrown when `tool_resource === EToolResources.file_search` AND the uploaded file's mimetype starts with `image/`. The file_search tool indexes text for retrieval; images are not parsable for the vector store and would be silently ignored, so the server rejects them early. This guard runs before capability checks.

Source

Thrown at api/server/services/Files/process.js:682

 * @param {ServerRequest} params.req - The Express request object.
 * @param {Express.Response} params.res - The Express response object.
 * @param {FileMetadata} params.metadata - Additional metadata for the file.
 * @param {import('@librechat/api').UploadSseStream | null} [params.sseStream] - Active upload SSE stream, if enabled.
 * @returns {Promise<void>}
 */
const processAgentFileUpload = async ({ req, res, metadata, sseStream }) => {
  const { file } = req;
  const appConfig = req.config;
  const { agent_id, tool_resource, file_id, temp_file_id = null } = metadata;

  let messageAttachment = !!metadata.message_file;

  if (agent_id && !tool_resource && !messageAttachment) {
    throw new Error('No tool resource provided for agent file upload');
  }

  if (tool_resource === EToolResources.file_search && file.mimetype.startsWith('image')) {
    throw new Error('Image uploads are not supported for file search tool resources');
  }

  if (!messageAttachment && !agent_id) {
    throw new Error('No agent ID provided for agent file upload');
  }

  const isImage = file.mimetype.startsWith('image');
  let fileInfoMetadata;
  const entity_id = messageAttachment === true ? undefined : agent_id;
  const basePath = mime.getType(file.originalname)?.startsWith('image') ? 'images' : 'uploads';
  if (tool_resource === EToolResources.execute_code) {
    const isCodeEnabled = await checkCapability(req, AgentCapabilities.execute_code);
    if (!isCodeEnabled) {
      throw new Error('Code execution is not enabled for Agents');
    }
    const { handleFileUpload: uploadCodeEnvFile } = getStrategyFunctions(FileSources.execute_code);
    const stream = fs.createReadStream(file.path);
    /* Resource identity for codeapi's sessionKey:

View on GitHub (pinned to 5ff282f900)

Solutions

Upload text-based documents (PDF, DOCX, TXT, MD) for file_search — not images.
Filter the file picker `accept` attribute by tool resource on the frontend.
If the user wants to attach an image, switch the tool_resource to one that supports images or send as a message_file.
Verify the file's actual MIME: a `.pdf` renamed to `.png` would still be detected as image by Multer's extension sniff.

Example fix

// before
<input type="file" />

// after
<input type="file" accept={toolResource === 'file_search' ? '.pdf,.docx,.txt,.md' : '*/*'} />

Defensive patterns

Strategy: validation

Validate before calling

function assertFileSearchMime(file, tool_resource) {
  if (tool_resource === 'file_search' && file.mimetype.startsWith('image/')) {
    throw new Error('file_search does not accept images');
  }
}

Try / catch

try { await processAgentFileUpload(params); }
catch (e) {
  if (/Image uploads are not supported for file search/.test(e.message)) return res.status(415).json({ error: e.message });
  throw e;
}

Prevention

Bind the file input's `accept` attribute to the active tool_resource.
Filter out images in the upload handler for file_search agents.
If the user wants to share an image, route it as a message_file or another tool_resource.

When it happens

Trigger: User attaches a PNG/JPG to an agent whose active tool_resource is `file_search`. The MIME is detected from `file.mimetype` (set by Multer from the uploaded filename/Content-Type) and matched against the literal prefix `image`.

Common situations: UI lets users drop any file type onto a file_search agent; a multi-file upload mixing PDFs and screenshots; frontend not filtering file types per tool resource; MIME sniffed wrong because the file has an image extension.

Related errors

AI-assisted analysis of danny-avila/LibreChat@5ff282f900 (2026-08-12). Data as JSON: /api/errors/0cee367ccbc398a6. Report an issue: GitHub.