v3: comments say what the code can't — the documentation pass wanted JSDoc on every export and every field of an exported interface, which filled the code with restatements ("The dump.", "Whether it is loading.", "The props of X.", "Renders the X.") and module docs that told a reader nothing ("The hot and new feeds, and the props every main feed of the index takes."); some were wrong as well as vague. Every comment in api/, shared/ and src/ is rewritten under one rule, now stated in the README's "Comments" section: every module and export still has a JSDoc, and it gives context (who uses it and where), usage (what a caller must know: a precondition, what it leaves to the caller, a side effect) or its place in the chain (where its input comes from, where its output goes); a field, parameter, private function or local gets one only when it adds to its parent's, and context about a whole type goes on the type; a type's doc is phrased from the value's side ("Returned to Y by X when Z", "Passed to Y by X"); full sentences, as short as they can be, no label-colon-list; // goes wherever the code isn't obvious and says why, and the section banners and narration go. Every claim was checked against the code, which turned up some forty comments that were wrong: DumpCard's claimed it was only used by the hot and new feeds, the WebSocket welcome claimed to be a socket's first message (presence comes first), UpdateUserRequest said null removes a description (it keeps it), deletedDumpIds leaves out that it also holds dumps made private, THEME_COLOR claimed to mirror index.html's, and the like. The routers' JSDoc now says where they are mounted and what becomes of a thrown APIException. doc-lint.ts lets a field without a doc through; a module or export without one still fails. No code changes; 204 backend and 628 frontend tests pass, and doc:lint, deno check, deno lint and tsc are clean.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

api/lib/slugify.ts

@@ -1,31 +1,37 @@
 /**
- * URL slugs for records that have a title.
+ * Builds the URL slugs of dumps and playlists from their titles. The dump and
+ * playlist services store the slug when the record is created or retitled.
  *
  * @module
  */
 
-/** A UUID, which a route parameter may carry instead of a slug. */
+/**
+ * Matches a UUID. A dump or playlist route takes either an id or a slug, and
+ * the services test the parameter with this to know which column to look up.
+ */
 export const UUID_RE =
   /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i;
 
 /**
- * Turns `title` into a URL-safe slug: lowercase ASCII, dash-separated, at most
- * 60 characters, `untitled` when nothing is left.
+ * Turns `title` into lowercase ASCII words joined by dashes, at most 60
+ * characters long. Accents are dropped, and a title with no ASCII letter or
+ * digit gives `untitled`.
  */
 export function slugify(title: string): string {
   const slug = title
     .toLowerCase()
     .normalize("NFD")
-    .replace(/[\u0300-\u036f]/g, "") // strip diacritics
-    .replace(/[^a-z0-9]+/g, "-") // non-alphanumeric → dash
-    .replace(/^-+|-+$/g, "") // trim leading/trailing dashes
+    // NFD splits an accented letter into the letter and a combining mark.
+    .replace(/[\u0300-\u036f]/g, "")
+    .replace(/[^a-z0-9]+/g, "-")
+    .replace(/^-+|-+$/g, "")
     .substring(0, 60);
   return slug || "untitled";
 }
 
 /**
- * Returns the slug of a record: its title's slug followed by the start of its
- * `id`, so it stays unique by construction.
+ * Returns a record's slug, its title's {@link slugify} followed by the first 8
+ * characters of `id`. The suffix keeps two records with the same title apart.
  */
 export function makeSlug(title: string, id: string): string {
   return `${slugify(title)}-${id.substring(0, 8)}`;