Made as simple as possible, but not simpler.
One powerful mechanism of robustness is exploratory behavior, for which the desired outcome is produced by a generate-and-test mechanism.
Resource description refers to defining concepts and relationships that represent the content and structure of some subject matter (ontology) or a database (schema) in a formal language.
In the Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH), a repository is a means of exposing metadata to harvesters.
Do your programs only compute pure functions of data, or do they also perform effects such as dynamically reading input, writing output, transitioning database state, making network requests, etc.