Command-line Interface
A command-line interface (CLI) is a text-based interface that allows users to interact with software by entering commands instead of using graphical controls.
“A type of interface in which the information is passed in form of command lines.”
(Definition reproduced from the ISTQB Glossary. Copyright belongs to ISTQB.)
View the complete ISTQB GlossaryWhat is Command-line Interface?
CLI applications accept textual commands and parameters, making them popular for system administration, automation, and scripting.
Text-based interaction: Users enter commands through a terminal.
Automation support: CLI tools integrate easily with scripts and pipelines.
Efficiency: Experienced users can perform tasks quickly without graphical interfaces.
Real World Example
An insurance claims platform is connecting a claim intake service, a policy validation service, and a payment approval service.
Each part can look correct in isolation while the handoff between parts still fails. Command-line interface helps testers focus on the boundary where data, timing, and responsibility meet.
The tester checks payloads, error handling, retries, missing fields, and the order of service calls instead of only confirming that each screen appears.
The claims flow becomes more dependable because Command-line interface exposes defects that only appear when real components collaborate.
Practice Questions
Question 1
Which is MOST critical for CLI automation?
Question 2
Which test BEST validates CLI piping support?
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