Enriched document-sensitivity metadata using contextual information

The technology disclosed includes a system to efficiently classify sensitivity of document generated by and downloaded from cloud-based provider services. The system monitors network traffic at a document-generation initiating endpoint and receives a web page identifying the document generated. The system parses the network traffic that selects the document for download, based on the user selecting a link, and intercepts a document handle in an API parameter string used to download the document. The system interprets the document handle to analyze sensitivity of the document to assign a sensitive classification to the document. The sensitivity classification is encoded into the document header metadata. The encoded sensitivity classification can be used to enhance security, for example, preventing data exfiltration.