This profile describes the vocabulary of the Term Usage Index page (terms.html) itself, not the API it indexes. The Term Usage Index is a meta-document: it lists the identifiers (parameter names and JSON Schema property names) that appear across the generated API documentation and records where each one is used. Because it talks *about* the documentation's vocabulary, its profile sits one level above the API profile (apidoc.xml) and above any application-level ALPS profile (which defines the domain meaning of terms such as `age` or `familyName`). Bind page elements to these descriptors by their `class` attribute: - a term entry carries `class="term"` (and `class="term alpsBacked"` when a same-name descriptor exists in the configured application ALPS profile); - the cross-reference to that application descriptor, when present, is carried by the `data-alps` attribute, not by `class`; - usage occurrences carry `class="usage"`, refined to `parameterUsage` or `schemaPropertyUsage`; - reserved representation fields carry `class="reservedField"`; - summary figures carry the matching count/coverage descriptor classes; - the whole document is bound by `class="termUsageIndex"` on its `main` element. Representation and navigation chrome is deliberately outside this vocabulary and carries no descriptor binding: the "API Documentation" back link, the `index-list` table of contents, and the `mark` checkmark are presentation only. Their absence from the binding set is intentional, not an omission. Matching is lexical (same identifier spelling); it does not assert semantic equivalence between the indexed term and the application descriptor. The index document. Lists every identifier used in the generated API documentation and where it appears. A companion view to the main API documentation (index.html), one meta level above it. An identifier used in the API: a request parameter name or a JSON Schema property name. The entry collects every place the identifier appears. Listing is by lexical spelling, so the same spelling used in unrelated places is collected under one entry. Marks a term whose spelling also exists as a descriptor id in the configured application ALPS profile (the `alps` setting in apidoc.xml). Shown with a checkmark. This is a lexical match only and does not prove that the indexed term and the application descriptor mean the same thing. The application descriptor id is exposed on the entry's `data-alps` attribute for cross-reference. Descriptor metadata (title, def, doc) shown on an ALPS-backed entry. The value is borrowed from the configured application ALPS profile for display; this index is not its authority. A `def` that is a URL links to the external vocabulary it references. One place where the term appears in the API documentation. The term is used as a request parameter of an endpoint, written as "parameter: METHOD /path {term}". Extracted from the resource method signature. The term is used as a JSON Schema property, written as "schema property: file.json#/json/pointer". Extracted from request and response schema files. A leading-underscore field such as `_links` or `_embedded`. Listed separately because it usually belongs to the representation format (HAL) rather than the API domain vocabulary. Number of distinct API terms collected (excluding reserved representation fields). Number of collected terms whose spelling matches a descriptor id in the configured application ALPS profile. alpsMatchedCount divided by termsUsedCount, as a percentage. A lexical coverage figure, not a semantic one. Number of distinct reserved representation fields collected.