Guide

Attachments

Users can attach documents and images to a message. The text of a document is read and given to the agent with the message.

Limits

	Limit
File types	Documents: TXT, MD, CSV, JSON, PDF. Images: PNG, JPEG, GIF, WebP.
Size	20 MB per file
Files per message	10
Text read from a document	Up to 20,000 characters per file and 30,000 per message; the rest is cut and the agent is told it was cut.

Where attachments work

The agent test chat, the chat widget, and the runtime API and SDKs. They do not work on the phone channel, the OpenAI-compatible endpoint or workflow chat: files sent there are ignored without an error (see Known beta limits).

From code

Upload first, then send the message with the attachment ids:

TypeScript

import { readFile } from 'node:fs/promises';
import { DezifiClient } from '@dezifi/client';

const client = new DezifiClient({
  baseUrl: 'https://api.dezifi.ai',
  apiKey: process.env.DEZIFI_SECRET_KEY,
  workspaceId: Number(process.env.DEZIFI_WORKSPACE_ID),
});
const asUser = client.onBehalfOf({ endUserId: 'user-123', customerGroupId: 'northwind' });

const file = await asUser.uploadAttachment(await readFile('contract.pdf'), 'contract.pdf', 'application/pdf');
const session = await asUser.agent(process.env.DEZIFI_AGENT_ID ?? '').startSession();
const reply = await session.send('Summarise the termination clause.', { attachmentIds: [file.id] });
console.log(reply.response);

Python

from pathlib import Path

as_user = client.on_behalf_of("user-123", "northwind")
file = as_user.upload_attachment(Path("contract.pdf").read_bytes(), "contract.pdf", "application/pdf")
session = as_user.agent(AGENT_ID).start_session()
reply = session.send("Summarise the termination clause.", attachment_ids=[file.id])
print(reply.response)

REST: POST /api/v1/runtime/agents/chat/attachments (multipart field file), then attachmentIds in the /execute body.

Errors your users may see

A file type that is not listed is refused with the list of accepted types.
A file over 20 MB is refused (HTTP 413). More than 10 files in a message is refused (HTTP 400).
A PDF with no selectable text (a scan) is refused with a message asking for a text PDF or pasted text.
A damaged or password-protected file is refused as unreadable.