> ## Documentation Index
> Fetch the complete documentation index at: https://signatureapi-daf4ee54.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Create a ceremony: Custom authentication

> Creates a ceremony where the recipient is authenticated externally to SignatureAPI. Use this to obtain a ceremony URL for sharing with recipients.

<Frame>
  <img src="https://mintcdn.com/signatureapi-daf4ee54/-zNb44iNHnnmKMui/docs/integrations/power-automate/images/actions/create-ceremony-custom.png?fit=max&auto=format&n=-zNb44iNHnnmKMui&q=85&s=960e70ab6b2f48acb94d52794abbdd0d" alt="" width="2880" height="1624" data-path="docs/integrations/power-automate/images/actions/create-ceremony-custom.png" />
</Frame>

### Input

<ParamField path="Authentication Provider" type="string" required={true}>
  The name of the authentication provider. This value is arbitrary and will appear in the audit logs of the envelope.
</ParamField>

<ParamField path="Authentication Data" type="array of string" required={true}>
  Key: Value pair containing authentication metadata. These details will be included in the envelope's audit logs
</ParamField>

<ParamField path="Recipient ID" type="string" required={true}>
  The ID of the recipient to which the ceremony will be created.
</ParamField>

<ParamField path="Redirect URL" type="string">
  A URL to redirect the recipient to after a ceremony is finished.

  [Learn more about ceremony redirect url](/docs/integrations/power-automate/recipients/redirect-url).
</ParamField>

<ParamField path="Extra Properties" type="string">
  Extra properties for extensibility.
</ParamField>

### Output

<ResponseField name="Ceremony URL" type="string">
  The URL the recipient must visit to initiate the ceremony
</ResponseField>