SignNow MCP Server

Instructions

Implementation Reference

• src/sn_mcp_server/tools/document.py:259-303 (handler)

  Core handler function _update_document_fields that loops through update requests and calls the SignNow API client.prefill_text_fields for each document.

  def _update_document_fields(client: SignNowAPIClient, token: str, update_requests: list[UpdateDocumentFields]) -> UpdateDocumentFieldsResponse:
      """
      Update fields for multiple documents.
  
      This function updates text fields in multiple documents using the SignNow API.
      Only text fields can be updated using the prefill_text_fields endpoint.
  
      Args:
          client: SignNow API client instance
          token: Access token for authentication
          update_requests: List of UpdateDocumentFields with document IDs and fields to update
  
      Returns:
          UpdateDocumentFieldsResponse with results for each document update
      """
  
      results = []
  
      for update_request in update_requests:
          try:
              # Convert FieldToUpdate to PrefillTextField format
              prefill_fields = []
              for field in update_request.fields:
                  prefill_fields.append({"field_name": field.name, "prefilled_text": field.value})
  
              # Create PrefillTextFieldsRequest
              from signnow_client.models.templates_and_documents import (
                  PrefillTextField,
                  PrefillTextFieldsRequest,
              )
  
              prefill_request = PrefillTextFieldsRequest(fields=[PrefillTextField(field_name=field.name, prefilled_text=field.value) for field in update_request.fields])
  
              # Update fields using the client
              success = client.prefill_text_fields(token=token, document_id=update_request.document_id, request_data=prefill_request)
  
              results.append(UpdateDocumentFieldsResult(document_id=update_request.document_id, updated=success, reason=None))  # No reason needed for success
  
          except Exception as e:
              # Log error and mark as failed
              error_message = str(e)
              print(f"Failed to update fields for document {update_request.document_id}: {error_message}")
              results.append(UpdateDocumentFieldsResult(document_id=update_request.document_id, updated=False, reason=error_message))
  
      return UpdateDocumentFieldsResponse(results=results)

• src/sn_mcp_server/tools/signnow.py:738-786 (registration)

  MCP tool registration and thin handler wrapper that authenticates and delegates to the core _update_document_fields implementation.

  @mcp.tool(
      name="update_document_fields",
      description="Update text fields in multiple documents (only individual documents, not document groups)",
      tags=["document", "fields", "update", "prefill"],
  )
  def update_document_fields(
      ctx: Context,
      update_requests: Annotated[
          list[UpdateDocumentFields],
          Field(
              description="Array of document field update requests",
              examples=[
                  [
                      {
                          "document_id": "abc123",
                          "fields": [
                              {"name": "FieldName1", "value": "New Value 1"},
                              {"name": "FieldName2", "value": "New Value 2"},
                          ],
                      },
                      {
                          "document_id": "def456",
                          "fields": [{"name": "FieldName3", "value": "New Value 3"}],
                      },
                  ],
              ],
          ),
      ],
  ) -> UpdateDocumentFieldsResponse:
      """Update text fields in multiple documents.
  
      This tool updates text fields in multiple documents using the SignNow API.
      Only text fields can be updated using the prefill_text_fields endpoint.
  
      IMPORTANT: This tool works only with individual documents, not document groups.
      To find out what fields are available in a document or document group,
      use the get_document tool first.
  
      Args:
          update_requests: Array of UpdateDocumentFields with document IDs and fields to update
  
      Returns:
          UpdateDocumentFieldsResponse with results for each document update
      """
      token, client = _get_token_and_client(token_provider)
  
      # Initialize client and use the imported function from document module
      return _update_document_fields(client, token, update_requests)

• src/sn_mcp_server/tools/models.py:374-400 (schema)

  Pydantic schema definitions for input (UpdateDocumentFields containing list of FieldToUpdate) and output (UpdateDocumentFieldsResponse with list of results).

  class FieldToUpdate(BaseModel):
      """Single field to update in a document."""
  
      name: str = Field(..., description="Name of the field to update")
      value: str = Field(..., description="New value for the field")
  
  
  class UpdateDocumentFields(BaseModel):
      """Request model for updating document fields."""
  
      document_id: str = Field(..., description="ID of the document to update")
      fields: list[FieldToUpdate] = Field(..., description="Array of fields to update with their new values")
  
  
  class UpdateDocumentFieldsResult(BaseModel):
      """Result of updating document fields."""
  
      document_id: str = Field(..., description="ID of the document that was updated")
      updated: bool = Field(..., description="Whether the document fields were successfully updated")
      reason: str | None = Field(None, description="Reason for failure if updated is false")
  
  
  class UpdateDocumentFieldsResponse(BaseModel):
      """Response model for updating document fields."""
  
      results: list[UpdateDocumentFieldsResult] = Field(..., description="Array of update results for each document")