Tell me, what should be the initial prompt to immediately get such a diagram as the last one.

To immediately obtain the required diagram, the prompt must be as specific as possible and include the following elements:

• Clear indication of the type of diagram (e.g., "create a sequence diagram" or "class diagram").
• Description of key entities, processes, or components to be reflected.
• Specification of the output format (e.g., PlantUML, Mermaid, or another markup language).
• If necessary — an example or template to guide.

Example prompt:

Create a sequence diagram in Mermaid format showing the user authentication process: the user enters login and password, the system checks the data, and returns the result.

Such a prompt helps the system generate the needed diagram immediately without additional clarifications.