Unstructured Transform MCP server installation for Sim

Sim is a workspace for building and running AI agents and workflows. It connects directly to the hosted Transform MCP server, which gives Sim agents access to document transformation tools. Sim’s starter template configures the server URL, transport, and authentication header for you.

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Requirements

You will need:

• A Sim account and workspace with a model provider configured. Sign in to Sim.
• An Unstructured API key. Get an API key.

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Add the Transform MCP server

Add your Unstructured API key as a Sim secret, and then use the starter template to configure the Transform MCP server.

1. In Sim, open your workspace Settings, and then click Secrets.
2. Under Workspace, add a secret named UNSTRUCTURED_API_KEY with your Unstructured API key as its value.
3. Click Save.
4. In Settings, click MCP Tools, and then click Add.
5. Under Starter templates, click Unstructured Transform. Sim fills in the following configuration:
   Name: Unstructured Transform
   Transport: streamable-http
   URL: https://mcp.transform.unstructured.io
   Authorization: Bearer {{UNSTRUCTURED_API_KEY}}
   Timeout: 30000
   
6. Click Test Connection. Sim should find these four tools:
   • request_file_upload_url
   • transform_files
   • check_transform_status
   • get_transform_results
7. Click Add MCP.

If the starter template is not available, enter the same configuration manually. When you type {{ in the authorization header, select UNSTRUCTURED_API_KEY from the secrets list. For a self-hosted Sim instance that sets ALLOWED_MCP_DOMAINS, add mcp.transform.unstructured.io to the allowlist.

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Add the Transform tools to an agent

Attach all four Transform tools to an Agent block so the agent can run the complete transform job lifecycle.

1. Open a Sim workflow, and then add or select an Agent block.
2. In Tools, click Add tool.
3. Under MCP Servers, select Unstructured Transform, and then click Use all 4 tools.
4. Give the agent a public document URL and ask it to transform the document. For example:
   Use Unstructured Transform to transform this PDF into Markdown:
   https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf
   
   Wait for the job to complete, then return the element count and download URL for the result.
   
5. Run the workflow. The agent starts the transform, checks its status, and returns the element count and download URL.

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Parse your source files

Parsing requests have the following limits:

• Each file must be of a supported file type.
• Each file must be 50 MB or less in size.
• Each request must have 10 files or fewer.
• Only 5 requests can be running at a time.

The Transform MCP server reports these limits through its tool responses. Your Sim agent should notify you when a file exceeds 50 MB. It should also limit each request to 10 files and run no more than 5 requests at a time.

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Troubleshoot the connection

Use the following checks if Sim cannot connect to Transform or expose its tools to an agent.

• The starter template does not appear. Enter the configuration from this page manually.
• The connection returns 401 Unauthorized. Confirm the UNSTRUCTURED_API_KEY secret contains a valid key and the authorization header uses Bearer {{UNSTRUCTURED_API_KEY}}.
• The connection returns 404 Not Found. Use https://mcp.transform.unstructured.io without an added path such as /mcp.
• The Transform tools do not appear in an agent. Open Settings, click MCP Tools, refresh the server, and then add the refreshed tools to the agent.
• A self-hosted instance blocks the server. Add mcp.transform.unstructured.io to ALLOWED_MCP_DOMAINS.

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Next steps

• Control Transform file parsing output: Control how the Unstructured Transform MCP server instructs Transform to partition, enrich, chunk, and embed the data based on your files.
• Control Transform structured data extraction: Control how the Unstructured Transform MCP server extracts and formats structured data from your files.
• Control Transform generated sample code: Control how the Unstructured Transform MCP server generates sample curl or Python code that demonstrates how to use Transform to partition, enrich, chunk, and embed the data based on your files.

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Questions? Need help?

• For technical support, request support.