Delimiters

Also known as: prompt delimiters, section markers

Delimiters are syntactic markers — such as XML tags, triple backticks, or dashed lines — used to separate distinct sections within a prompt, such as instructions from context, context from user input, or examples from the task. Clear delimiters reduce the risk that the model conflates injected content with trusted instructions, making them an important defense against prompt injection. They also help the model locate the correct section to attend to when processing complex multi-part prompts.