vellum-ai/chat-complex-documents

What this does (in plain terms)

You have documents — contracts, reports, slide decks, scanned PDFs, spreadsheets, emails, images — and you want the assistant to reliably get the content _out_ of them and make it usable: searchable, answerable, summarizable, or ready to feed a knowledge base or another tool.

Unstructured Transform does exactly that. Hand it files and it turns them into clean, structured, AI-ready data across 60+ formats with one pipeline — no custom parsing or OCR to build and maintain. See the Transform overview.

Under the hood it:

• Partitions each document into structured elements (titles, paragraphs, tables, lists), adjusting extraction per page for accuracy and cost.
• Enriches the result with metadata, table and image descriptions, and entity recognition.

The result is structured JSON that's ready for search, Q&A, summarization, and agents.

Why people use it

• Make documents searchable and answerable. Transform extracts clean, structured text and tables from your files so the assistant can search them and answer questions grounded in the source.
• Handle messy, varied files. One integration covers 60+ formats (scanned PDFs, tables, images, Office files) instead of a per-format parser.

When to use

USE THIS SKILL WHEN:

• The user wants to extract or structure content from documents (PDF, Office, images, emails, scanned files).
• The user wants documents made searchable or ready for RAG / Q&A / a knowledge base.
• The user asks to connect Unstructured or Unstructured Transform.
• A Transform tool returns an auth error → re-run the auth step below.

Prerequisites

• An Unstructured account to sign in with during the OAuth step (a free tier is available). See pricing.
• Nothing to install locally — Transform is a hosted MCP server.

Setup

Step 1 — Detect your environment

Determine which command tool to use for every command in this skill:

• If host_bash is available → you are on the desktop app. Use host_bash for all commands (the auth step opens your local browser).
• If it is unavailable → you are on the web app. Use bash for all commands (the platform handles the browser redirect).

Step 2 — Add the server

Add Transform as a remote streamable-http MCP server. Keep the default risk level (high) — Transform ingests file content, so per-call approval is the safe default.

assistant mcp add unstructured-transform -t streamable-http -u https://mcp.transform.unstructured.io

The server is registered under the id unstructured-transform — that's the name shown by assistant mcp list and used in the commands below, even though this skill is titled "Chat with Complex Documents".

Step 3 — Authenticate via OAuth

assistant mcp auth unstructured-transform

This opens Unstructured's authorization page. After sign-in, the assistant handles the callback and caches the tokens.

• On desktop → run via host_bash (opens your local browser).
• On web app → run via bash (the platform handles the redirect).

Step 4 — Verify

assistant mcp list

Confirm unstructured-transform shows ✓ Connected. If it shows ! Needs authentication, re-run Step 3. If its tools don't appear within ~10 seconds, run assistant mcp reload.

Using Transform

Once connected, ask the assistant in plain language, e.g. _"Use Unstructured Transform to parse these files and return one JSON file per source file,"_ or _"Extract the tables from this PDF."_ Transform partitions each file and returns structured output; to tune partitioning and enrichment behavior, see Control Transform output.

Per-request limits (Transform enforces these; plan around them):

• Each file must be a supported file type.
• Each file must be 50 MB or less.
• Each request may include 10 files or fewer.
• At most 5 requests may run at a time.

Disconnecting

assistant mcp remove unstructured-transform

This removes the config entry and cleans up the stored OAuth credentials.

SKILL COMPLETE WHEN

• Connect: unstructured-transform appears in assistant mcp list as ✓ Connected and the user confirms its tools are available in the conversation.
• Disconnect: assistant mcp remove unstructured-transform succeeds and the server no longer appears in assistant mcp list.