MCP tools

Reference for all tools exposed by the Paubox MCP Server.

The Paubox MCP Server exposes five tools. Each tool maps to an underlying Paubox API operation and is available to any connected MCP client.

send_secure_email

Sends a single HIPAA compliant email through the Paubox Email API. The sender address must belong to a domain you have verified in the Paubox dashboard.

Parameter	Type	Required	Description
from	string	Yes	Sender address. Must be on a verified Paubox domain.
to	array of strings	Yes	Recipient email addresses.
subject	string	Yes	Email subject line.
message	string	Yes	Message body. Sent as plain text; the server also generates an HTML version automatically.
cc	array of strings	No	CC recipients.
bcc	array of strings	No	BCC recipients.
forceSecureNotification	boolean	No	Force a secure notification regardless of recipient settings. Defaults to false.
apiKey	string	No	Paubox API key. HTTP transport only; overrides the credential resolved from the connector or headers.
apiUser	string	No	Paubox API user. HTTP transport only; overrides the credential resolved from the connector or headers.

Example payload

{
  "from": "[e-mail]",
  "to": ["[e-mail]"],
  "subject": "Your appointment summary",
  "message": "Thank you for visiting us today."
}

Response: returns a sourceTrackingId string you can pass to check_email_status.

check_email_status

Retrieves the current delivery status of a message sent via send_secure_email.

Parameter	Type	Required	Description
sourceTrackingId	string	Yes	The tracking ID returned by send_secure_email.
apiKey	string	No	Paubox API key. HTTP transport only.
apiUser	string	No	Paubox API user. HTTP transport only.

Example payload

{
  "sourceTrackingId": "abc123def456"
}

Response: returns an object with delivery disposition details and a timestamp.

validate_credentials

Verifies that the Paubox API credentials are present and valid by making a live check against the Paubox API. Useful as a first step before sending email.

Parameter	Type	Required	Description
apiKey	string	No	Paubox API key. HTTP transport only; pass if you want to validate specific credentials rather than the ones already configured.
apiUser	string	No	Paubox API user. HTTP transport only.

When connecting via stdio (Claude Code), credentials come from environment variables and no parameters are needed.

Example payload

{}

Response: returns a confirmation with the API user and a masked API key on success, or an error description if the credentials are missing or invalid.

get_form

Available via HTTP transport only. Not available when using the stdio transport (Claude Code).

Retrieves the full definition of a Paubox Form, including its title, description, and field schema, so an agent can present the form questions in a conversation. No authentication is required for this tool.

Parameter	Type	Required	Description
formId	string (UUID)	Yes	UUID of the Paubox Form to retrieve.

Example payload

{
  "formId": "550e8400-e29b-41d4-a716-446655440000"
}

Response: returns a form object including title, description, form_json (field definitions), and metadata fields (active, signable, submission_count, created_at, updated_at).

submit_form

Available via HTTP transport only. Not available when using the stdio transport (Claude Code).

Submits a completed response to a Paubox Form. No authentication is required for this tool.

Parameter	Type	Required	Description
formId	string (UUID)	Yes	UUID of the form being submitted.
formData	object	Yes	Key-value pairs matching the form’s field schema (form_json). Structure varies per form.
attachments	array of objects	No	File attachments. Each object must include name (filename) and content (base64-encoded file). Max total size: 250 MB.

Example payload: text fields only

{
  "formId": "550e8400-e29b-41d4-a716-446655440000",
  "formData": {
    "first_name": "Jane",
    "last_name": "Smith",
    "email": "[e-mail]"
  }
}

Example payload: with attachment

{
  "formId": "550e8400-e29b-41d4-a716-446655440000",
  "formData": {
    "first_name": "Jane"
  },
  "attachments": [
    {
      "name": "consent.pdf",
      "content": "JVBERi0xLjQ..."
    }
  ]
}

Response: returns a success confirmation message on success.