XML tags in prompts
XML tags in prompts are paired markers such as `<context>` and `</context>` used to label each section of a prompt so the model can tell them apart.
Anthropic’s models were trained with XML-delimited structure and follow it more reliably than markdown headings, particularly in long prompts. The tag names are arbitrary; what matters is that they are consistent and that every opened tag is closed.
Related terms
- Delimiter
- A delimiter is a marker such as an XML tag, a row of dashes, or triple backticks that separates one part of a prompt from another.
- Prompt structure
- Prompt structure is the order and separation of a prompt’s parts — role, context, task, constraints, format, examples — which changes model behaviour independently of the words used.
More on prompt structure
See the full glossary, read the guides, or put it into practice in the prompt builder.