MCP Google Contacts Server

Instructions

    Args:
        resource_name: Contact resource name (people/*)
        given_name: Updated first name
        family_name: Updated last name
        email: Updated email address
        phone: Updated phone number
    

Implementation Reference

• mcp_google_contacts_server/tools.py:122-149 (handler)

  The primary MCP tool handler for the 'update_contact' tool. This async function is decorated with @mcp.tool(), which registers it with the MCP server. It initializes the GoogleContactsService, calls the service's update_contact method, formats the result using format_contact, and returns a success or error message.

  @mcp.tool()
  async def update_contact(resource_name: str, given_name: Optional[str] = None, 
                         family_name: Optional[str] = None, email: Optional[str] = None,
                         phone: Optional[str] = None) -> str:
      """Update an existing contact.
      
      Args:
          resource_name: Contact resource name (people/*)
          given_name: Updated first name
          family_name: Updated last name
          email: Updated email address
          phone: Updated phone number
      """
      service = init_service()
      if not service:
          return "Error: Google Contacts service is not available. Please check your credentials."
      
      try:
          contact = service.update_contact(
              resource_name,
              given_name,
              family_name,
              email,
              phone
          )
          return f"Contact updated successfully!\n\n{format_contact(contact)}"
      except Exception as e:
          return f"Error: Failed to update contact - {str(e)}"

• mcp_google_contacts_server/google_contacts_service.py:309-358 (helper)

  Supporting helper method in the GoogleContactsService class that performs the actual API interaction to update a contact. It fetches the current contact, prepares the update body and fields mask, and calls the Google People API's updateContact method.

  def update_contact(self, resource_name: str, given_name: Optional[str] = None, 
                    family_name: Optional[str] = None, email: Optional[str] = None,
                    phone: Optional[str] = None) -> Dict:
      """Update an existing contact."""
      try:
          # Get the etag for the contact first
          person = self.service.people().get(
              resourceName=resource_name,
              personFields='names,emailAddresses,phoneNumbers'
          ).execute()
          
          etag = person.get('etag')
          
          # Prepare update masks and body
          update_person = {'etag': etag, 'resourceName': resource_name}
          update_fields = []
          
          # Update name if provided
          if given_name or family_name:
              current_name = person.get('names', [{}])[0]
              update_person['names'] = [{
                  'givenName': given_name if given_name is not None else current_name.get('givenName', ''),
                  'familyName': family_name if family_name is not None else current_name.get('familyName', '')
              }]
              update_fields.append('names')
          
          # Update email if provided
          if email:
              update_person['emailAddresses'] = [{'value': email}]
              update_fields.append('emailAddresses')
          
          # Update phone if provided
          if phone:
              update_person['phoneNumbers'] = [{'value': phone}]
              update_fields.append('phoneNumbers')
          
          # Execute update
          if update_fields:
              updated_person = self.service.people().updateContact(
                  resourceName=resource_name,
                  updatePersonFields=','.join(update_fields),
                  body=update_person
              ).execute()
              
              return self._format_contact(updated_person)
          else:
              return self._format_contact(person)
      
      except HttpError as error:
          raise GoogleContactsError(f"Error updating contact: {error}")

• mcp_google_contacts_server/main.py:83-84 (registration)

  The call to register_tools(mcp) in the main server setup, which defines and registers all tools including update_contact via @mcp.tool() decorators inside the register_tools function.

  # Register all tools
  register_tools(mcp)

• mcp_google_contacts_server/tools.py:126-134 (schema)

  The docstring providing the input schema/parameter descriptions for the update_contact tool, used by MCP for tool schema generation.

  """Update an existing contact.
  
  Args:
      resource_name: Contact resource name (people/*)
      given_name: Updated first name
      family_name: Updated last name
      email: Updated email address
      phone: Updated phone number
  """