XML
Also: Extensible Markup Language
A way of labelling parts of a text with tags, like <date>12 March</date>, so a program knows what each part is.
The fuller definition
XML means Extensible Markup Language. It represents structured data with named tags and nesting; similar tags are also used to organize prompts.
- Open tag
<record>
- Content
Source text
- Close tag
</record>
A simplified relationship, not a screenshot or a complete design.
A concrete example
A prompt labels source material inside <record> and the task inside <instructions>.
The distinction that matters
Tagging helps distinguish sections but is not an enforced security boundary against prompt injection.
Related terms
Prompt
What you give a model to guide its reply. This may include a question, rules, and source text.
Reliability & securityPrompt injection
Text in a source that tries to redirect an AI tool. It may tell the tool to ignore your rules or leak data.
APIs & softwareJSON — JavaScript Object Notation
A tidy text format for data, made of labels and values in curly brackets. Programs use it to pass information around.
Where it is taught
Give AI a brief it can actually followSource and further reading
Anthropic · Context engineeringThe definition and example are written for this library. The link gives background, official documentation or legal authority as labelled. Legal scope depends on the jurisdiction and current text; product features depend on release and settings.