User-System Interaction Sequence Diagram

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Mermaid

Visualize interactions between users and your system step by step. This sequence diagram helps identify message flow, dependencies, and timing for feature design, testing, or documentation.

How to create a System Sequence Diagram

To create a system sequence diagram, follow these steps:

01.
Identify actors
Determine users or external systems interacting with your system.
02.
Define system boundaries
Clarify what is inside versus outside the system.
03.
List interactions
Identify messages or events exchanged between actors and the system.
04.
Draw lifelines
Represent each actor and the system as vertical dashed lines.
05.
Add messages
Use arrows to show requests, responses, and data flow.
06.
Sequence events
Place messages top-to-bottom in chronological order.
07.
Validate with stakeholders
Ensure the diagram accurately reflects the process.
08.
Finalize & share
Use it for development, testing, or documentation.

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Tags

Sequence DiagramUser InteractionSystem FlowMessage FlowProcess VisualizationDocumentationFeature Design

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