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>

src/contexts/social/FollowProvider.tsx

@@ -1,6 +1,6 @@
 /**
- * The follows' provider: what the signed-in user follows, changed
- * optimistically.
+ * Provides `FollowContext`, from `GET /api/follows/status`. `App` mounts it
+ * around every page.
  *
  * @module
  */
@@ -17,16 +17,15 @@ import { API_URL } from "../../config/api.ts";
 import { useAuth } from "../../hooks/auth/useAuth.ts";
 import type { FollowStatus } from "../../../shared/follow.ts";
 
-/** The props of {@link FollowProvider}. */
+/** Passed to {@link FollowProvider} by `App`. */
 export interface FollowProviderProps {
-  /** The app, which reads and changes the follows. */
   children: ReactNode;
 }
 
 /**
- * Provides {@link FollowContext}: fetches the follow status when someone signs
- * in, clears it when they sign out. A follow or unfollow applies at once and is
- * rolled back if the request fails.
+ * Provides {@link FollowContext}. It fetches the follows whenever the token
+ * changes, and empties them on sign-out. Follows made in another tab don't
+ * show until the next sign-in or reload: no socket message carries them.
  */
 export function FollowProvider(
   { children }: FollowProviderProps,
@@ -42,9 +41,8 @@ export function FollowProvider(
 
   useEffect(() => {
     if (!token) {
-      // Deferred to a microtask (rather than called directly) so this
-      // doesn't fire synchronously within the effect body — same timing
-      // for the user, just not in the same tick.
+      // The React hooks lint forbids a synchronous setState in an effect. The
+      // microtask changes nothing the user can see.
       queueMicrotask(() => {
         setFollowedUserIds(new Set());
         setFollowedPlaylistIds(new Set());
@@ -66,6 +64,7 @@ export function FollowProvider(
         setIsLoaded(true);
       })
       .catch((err) => {
+        // Enables the buttons anyway, though the sets may be empty or stale.
         if (err.name !== "AbortError") setIsLoaded(true);
       });
     return () => {