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>

shared/chat.ts

@@ -1,35 +1,31 @@
 /**
- * A message of the site-wide chat.
+ * Defines a message of the site-wide chat, as the server sends it to the
+ * chatbox.
  *
  * @module
  */
 
-/** A chat message, with what the chat shows of its author and its reply. */
+/**
+ * Returned by `GET /api/chat`, and sent by the server in `chat_message` and
+ * `chat_message_updated`. The client reads it through
+ * `deserializeChatMessage`, which turns its dates back into Dates.
+ */
 export interface ChatMessage {
-  /** The message's id. */
   id: string;
-  /** The author's id. */
   userId: string;
-  /** The message, in Markdown. */
+  /** In Markdown, trimmed by the server. */
   body: string;
-  /** When the message was sent. */
   createdAt: Date;
-  /** When the message was last edited, if ever. */
+  /** Absent until the first edit. */
   updatedAt?: Date;
-  /** The author's name. */
   authorUsername: string;
-  /** The author's avatar type, undefined without one. */
   authorAvatarMime?: string;
   /**
-   * Id of the message this one replies to, if any. Retained even when the
-   * target is later deleted (the preview fields below then go undefined).
+   * Kept when the message it points to is deleted, while `replyToAuthor` and
+   * `replyToBody` then go absent.
    */
   replyToId?: string;
-  /**
-   * Author of the replied-to message, for a subtle inline reference. Absent
-   * when there's no reply, or the target has since been deleted.
-   */
   replyToAuthor?: string;
-  /** Body of the replied-to message, absent under the same conditions. */
+  /** The first 300 characters of the replied-to body, in Markdown. */
   replyToBody?: string;
 }