Some Cyc results and output are available as XML files. The following XSDs describe the most commonly used Cyc XML outputs:

Cyc Concepts XML schema for Cyc concepts. Download
Cyc ML XML schema for CycL terms, including constants, formulas, assertions, etc. Download
CycL Query XML schema for CycL query specifications, including query sentence, microtheory, and inference parameters. Download
Formula Template XML schema for formula templates. Used for loading CycL query specifications from a Cyc image. Download
Lightweight Result Set XML schema for minimal result sets used for autocomplete and simple query results. Download
Proof View XML schema for proof-views, a natural-language justification format. Download
Text Processing XML schema for text processing results. Download