When defining a document in an envelope, you must provide either a PDF Document or a DOCX template.

There are several ways to provide a file to be used as a document in SignatureAPI:

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Upload via Dashboard

You can manually upload document or template files to your account’s Library in the Dashboard.

Files uploaded to your Library never expire and can be reused across multiple envelopes. This method is ideal if you work with a small set of recurring documents or templates.

To upload files to your Library, go to the Library tab in the Dashboard.

Click Upload a file or drag and drop your file, then confirm the upload. Click the Copy URL button to copy the file URL to your clipboard. You can use this URL when defining your document:

// POST /v1/envelopes
{
  "title": "Dummy Agreement",
  "documents": [
    {
      "url": "https://api.signatureapi.com/v1/files/abc123#dummy-agreement-v1"
      //...
    }
  ],
  "recipients": [
    //...
  ]
  //...
}

​
Upload via API

You can programmatically upload document or template files to SignatureAPI using the Create File endpoint.

Files uploaded via the API are temporary and intended for immediate use. If you plan to reuse a file, consider uploading it to your Library in the Dashboard (see above).

Uploading via the API is a two-step process:

1

Create a Temporary File

First, create a temporary file resource by sending a POST request to https://api.signatureapi.com/v1/files. The response will look like this:

{
  "id": "fil_0nZXZ8pYPByQ4XksJbDl4r",
  "put_url": "https://s3.us-east-2.amazonaws.com/signatureapi-vault-dev/temp...",
  "expires_at": "2025-12-31T20:00:00.000Z"
}

Note the put_url property. The Location header in the response also contains the File URL:

Location: https://api.signatureapi.com/v1/files/fil_0nZXZ8pYPByQ4XksJbDl4r
2

Upload Your File

Next, upload your file to the put_url using a PUT request.

Ensure you upload the file as a binary stream. Multipart uploads add extra content that can corrupt the file.

Here are some examples:

curl -X PUT \
  --upload-file path/to/template.docx \
  "https://s3.us-east-2.amazonaws.com/signatureapi-vault/temp..."

Finally, use the File URL (from the Location header in step 1) as the url parameter when defining your document:

// POST /v1/envelopes
{
  "title": "Dummy Agreement",
  "documents": [
    {
      "url": "https://api.signatureapi.com/v1/files/fil_0nZXZ8pYPByQ4XksJbDl4r"
      //...
    }
  ],
  "recipients": [
    //...
  ]
  //...
}

​
External Store

As an alternative to uploading, you can provide a publicly accessible URL to your file using the url parameter. SignatureAPI will download the document or template from the specified location.

Supported sources include: