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/routes/follows.ts

@@ -1,5 +1,6 @@
 /**
- * The follow routes, all for what the caller follows.
+ * Serves the endpoints for what the caller follows, and the index's "followed"
+ * tab built from it. What another user follows is served by `routes/users.ts`.
  *
  * - `GET /api/follows/status` — signed in. Answers the ids of the users and
  *   playlists they follow.
@@ -37,10 +38,9 @@ import {
 import { getCategoryIdBySlug } from "../services/category-service.ts";
 
 /**
- * Resolves the optional ?category=<slug> filter. Returns the matching category
- * id, or "missing" when a slug was given but matches nothing (so the feed comes
- * back empty rather than unfiltered), or undefined when no filter was
- * requested.
+ * Returns the id of the category the `?category=` slug names, undefined without
+ * one, or "missing" when it names none, so that the feed comes back empty
+ * rather than unfiltered.
  */
 function resolveCategoryFilter(
   params: URLSearchParams,
@@ -50,14 +50,14 @@ function resolveCategoryFilter(
   return getCategoryIdBySlug(slug) ?? "missing";
 }
 
-/** The feed a filter naming no category yields. */
 const EMPTY_FEED: Page<Dump> = { items: [], hasMore: false };
 
-/** The router serving the endpoints the module doc lists. */
+/**
+ * Mounted by `api/main.ts` behind the error, Open Graph and CORS middleware.
+ * An `APIException` thrown by a handler becomes the JSON error response there.
+ */
 const router: Router = new Router({ prefix: "/api/follows" });
 
-// Static routes first to prevent Oak matching "status"/"feed" as a :param
-
 router.get("/status", authMiddleware, (ctx) => {
   const status = getFollowStatus(ctx.state.user.userId);
   const body: APIResponse<FollowStatus> = { success: true, data: status };