diff --git a/js/nostr.js b/js/nostr.js
index 4746aaa2..afbbd8bf 100644
--- a/js/nostr.js
+++ b/js/nostr.js
@@ -22,6 +22,36 @@ export const publishVideoReaction = (...args) => {
   return defaultNostrClient.publishVideoReaction(...args);
 };
 
+export const publishVideoComment = (...args) => {
+  if (
+    !defaultNostrClient ||
+    typeof defaultNostrClient.publishVideoComment !== "function"
+  ) {
+    throw new Error("Video comment publishing is unavailable in this build.");
+  }
+  return defaultNostrClient.publishVideoComment(...args);
+};
+
+export const fetchVideoComments = (...args) => {
+  if (
+    !defaultNostrClient ||
+    typeof defaultNostrClient.fetchVideoComments !== "function"
+  ) {
+    throw new Error("Video comment fetching is unavailable in this build.");
+  }
+  return defaultNostrClient.fetchVideoComments(...args);
+};
+
+export const subscribeVideoComments = (...args) => {
+  if (
+    !defaultNostrClient ||
+    typeof defaultNostrClient.subscribeVideoComments !== "function"
+  ) {
+    throw new Error("Video comment subscriptions are unavailable in this build.");
+  }
+  return defaultNostrClient.subscribeVideoComments(...args);
+};
+
 export {
   __testExports,
   NostrClient,
diff --git a/js/nostr/client.js b/js/nostr/client.js
index b73bd5bc..6aa52737 100644
--- a/js/nostr/client.js
+++ b/js/nostr/client.js
@@ -53,6 +53,11 @@ import {
   recordVideoView as recordVideoViewForClient,
 } from "./viewEvents.js";
 import { publishVideoReaction as publishVideoReactionForClient } from "./reactionEvents.js";
+import {
+  publishComment as publishCommentForClient,
+  listVideoComments as listVideoCommentsForClient,
+  subscribeVideoComments as subscribeVideoCommentsForClient,
+} from "./commentEvents.js";
 import {
   publishEventToRelay,
   publishEventToRelays,
@@ -2757,6 +2762,23 @@ export class NostrClient {
     });
   }
 
+  async publishVideoComment(target, options = {}) {
+    return publishCommentForClient(this, target, options, {
+      resolveActiveSigner,
+      shouldRequestExtensionPermissions,
+      signEventWithPrivateKey,
+      DEFAULT_NIP07_PERMISSION_METHODS,
+    });
+  }
+
+  async fetchVideoComments(target, options = {}) {
+    return listVideoCommentsForClient(this, target, options);
+  }
+
+  subscribeVideoComments(target, options = {}) {
+    return subscribeVideoCommentsForClient(this, target, options);
+  }
+
   async recordVideoView(videoPointer, options = {}) {
     return recordVideoViewForClient(this, videoPointer, options, {
       resolveActiveSigner,
diff --git a/js/nostr/commentEvents.js b/js/nostr/commentEvents.js
new file mode 100644
index 00000000..727a46ad
--- /dev/null
+++ b/js/nostr/commentEvents.js
@@ -0,0 +1,650 @@
+import {
+  buildCommentEvent,
+  getNostrEventSchema,
+  NOTE_TYPES,
+} from "../nostrEventSchemas.js";
+import { publishEventToRelay } from "../nostrPublish.js";
+import { RELAY_URLS } from "./toolkit.js";
+import { normalizePointerInput } from "./watchHistory.js";
+import { devLogger, userLogger } from "../utils/logger.js";
+
+const COMMENT_EVENT_SCHEMA = getNostrEventSchema(NOTE_TYPES.VIDEO_COMMENT);
+export const COMMENT_EVENT_KIND = Number.isFinite(COMMENT_EVENT_SCHEMA?.kind)
+  ? COMMENT_EVENT_SCHEMA.kind
+  : 1;
+
+function sanitizeRelayList(primary, fallback) {
+  if (Array.isArray(primary) && primary.length) {
+    return primary;
+  }
+  if (Array.isArray(fallback) && fallback.length) {
+    return fallback;
+  }
+  return RELAY_URLS;
+}
+
+function normalizeRelay(candidate) {
+  if (typeof candidate === "string" && candidate.trim()) {
+    return candidate.trim();
+  }
+  if (Array.isArray(candidate)) {
+    const relayCandidate = candidate[2];
+    if (typeof relayCandidate === "string" && relayCandidate.trim()) {
+      return relayCandidate.trim();
+    }
+  }
+  if (candidate && typeof candidate === "object") {
+    if (typeof candidate.relay === "string" && candidate.relay.trim()) {
+      return candidate.relay.trim();
+    }
+    if (typeof candidate.url === "string" && candidate.url.trim()) {
+      return candidate.url.trim();
+    }
+    if (Array.isArray(candidate.relays)) {
+      for (const relayCandidate of candidate.relays) {
+        if (typeof relayCandidate === "string" && relayCandidate.trim()) {
+          return relayCandidate.trim();
+        }
+      }
+    }
+    if (candidate.tag) {
+      return normalizeRelay(candidate.tag);
+    }
+    if (candidate.pointer) {
+      return normalizeRelay(candidate.pointer);
+    }
+  }
+  return "";
+}
+
+function normalizePointerCandidate(candidate, expectedType) {
+  if (!candidate) {
+    return null;
+  }
+
+  if (Array.isArray(candidate)) {
+    if (
+      candidate[0] === expectedType &&
+      typeof candidate[1] === "string" &&
+      candidate[1].trim()
+    ) {
+      return {
+        value: candidate[1].trim(),
+        relay: normalizeRelay(candidate),
+      };
+    }
+    return null;
+  }
+
+  if (typeof candidate === "string") {
+    const pointer = normalizePointerInput(candidate);
+    if (pointer?.type === expectedType && pointer.value) {
+      return {
+        value: pointer.value.trim(),
+        relay: normalizeRelay(pointer),
+      };
+    }
+    if (expectedType === "e" && candidate.trim() && !candidate.includes(":")) {
+      return { value: candidate.trim(), relay: "" };
+    }
+    if (expectedType === "a" && candidate.trim() && candidate.includes(":")) {
+      return { value: candidate.trim(), relay: "" };
+    }
+    return null;
+  }
+
+  if (candidate && typeof candidate === "object") {
+    if (
+      typeof candidate.type === "string" &&
+      candidate.type === expectedType &&
+      typeof candidate.value === "string" &&
+      candidate.value.trim()
+    ) {
+      return {
+        value: candidate.value.trim(),
+        relay: normalizeRelay(candidate),
+      };
+    }
+    if (
+      expectedType === "e" &&
+      typeof candidate.id === "string" &&
+      candidate.id.trim()
+    ) {
+      return {
+        value: candidate.id.trim(),
+        relay: normalizeRelay(candidate),
+      };
+    }
+    if (
+      expectedType === "a" &&
+      typeof candidate.address === "string" &&
+      candidate.address.trim()
+    ) {
+      return {
+        value: candidate.address.trim(),
+        relay: normalizeRelay(candidate),
+      };
+    }
+    if (candidate.tag) {
+      return normalizePointerCandidate(candidate.tag, expectedType);
+    }
+    if (candidate.pointer) {
+      return normalizePointerCandidate(candidate.pointer, expectedType);
+    }
+  }
+
+  return null;
+}
+
+function pickString(...candidates) {
+  for (const candidate of candidates) {
+    if (typeof candidate === "string" && candidate.trim()) {
+      return candidate.trim();
+    }
+  }
+  return "";
+}
+
+function normalizeCommentTarget(targetInput = {}, overrides = {}) {
+  const target = targetInput && typeof targetInput === "object" ? targetInput : {};
+  const options = overrides && typeof overrides === "object" ? overrides : {};
+
+  const videoEventPointer =
+    normalizePointerCandidate(options.videoEventPointer, "e") ||
+    normalizePointerCandidate(options.videoEvent, "e") ||
+    normalizePointerCandidate(target.videoEventPointer, "e") ||
+    normalizePointerCandidate(target.videoEvent, "e") ||
+    normalizePointerCandidate(target.eventPointer, "e") ||
+    normalizePointerCandidate(target.event, "e");
+
+  const videoDefinitionPointer =
+    normalizePointerCandidate(options.videoDefinitionPointer, "a") ||
+    normalizePointerCandidate(options.videoDefinition, "a") ||
+    normalizePointerCandidate(target.videoDefinitionPointer, "a") ||
+    normalizePointerCandidate(target.videoDefinition, "a") ||
+    normalizePointerCandidate(target.definitionPointer, "a") ||
+    normalizePointerCandidate(target.definition, "a");
+
+  const parentCommentPointer =
+    normalizePointerCandidate(options.parentCommentPointer, "e") ||
+    normalizePointerCandidate(options.parentComment, "e") ||
+    normalizePointerCandidate(target.parentCommentPointer, "e") ||
+    normalizePointerCandidate(target.parentComment, "e") ||
+    normalizePointerCandidate(target.parentPointer, "e");
+
+  const videoEventId = pickString(
+    options.videoEventId,
+    target.videoEventId,
+    target.eventId,
+    videoEventPointer?.value,
+  );
+  const videoEventRelay = pickString(
+    options.videoEventRelay,
+    target.videoEventRelay,
+    target.eventRelay,
+    videoEventPointer?.relay,
+  );
+
+  const videoDefinitionAddress = pickString(
+    options.videoDefinitionAddress,
+    target.videoDefinitionAddress,
+    target.definitionAddress,
+    videoDefinitionPointer?.value,
+  );
+  const videoDefinitionRelay = pickString(
+    options.videoDefinitionRelay,
+    target.videoDefinitionRelay,
+    target.definitionRelay,
+    videoDefinitionPointer?.relay,
+  );
+
+  const parentCommentId = pickString(
+    options.parentCommentId,
+    target.parentCommentId,
+    target.parentId,
+    parentCommentPointer?.value,
+  );
+  const parentCommentRelay = pickString(
+    options.parentCommentRelay,
+    target.parentCommentRelay,
+    target.parentRelay,
+    parentCommentPointer?.relay,
+  );
+
+  const threadParticipantPubkey = pickString(
+    options.threadParticipantPubkey,
+    target.threadParticipantPubkey,
+    target.participantPubkey,
+    target.authorPubkey,
+  );
+  const threadParticipantRelay = pickString(
+    options.threadParticipantRelay,
+    target.threadParticipantRelay,
+    target.participantRelay,
+  );
+
+  if (!videoEventId || !videoDefinitionAddress) {
+    return null;
+  }
+
+  return {
+    videoEventId,
+    videoEventRelay,
+    videoDefinitionAddress,
+    videoDefinitionRelay,
+    parentCommentId,
+    parentCommentRelay,
+    threadParticipantPubkey,
+    threadParticipantRelay,
+  };
+}
+
+function createVideoCommentFilters(targetInput, options = {}) {
+  const descriptor = normalizeCommentTarget(targetInput, options);
+  if (!descriptor) {
+    throw new Error("Invalid video comment target supplied.");
+  }
+
+  const filter = {
+    kinds: [COMMENT_EVENT_KIND],
+    "#e": [descriptor.videoEventId],
+    "#a": [descriptor.videoDefinitionAddress],
+  };
+
+  if (descriptor.parentCommentId) {
+    if (!filter["#e"].includes(descriptor.parentCommentId)) {
+      filter["#e"].push(descriptor.parentCommentId);
+    }
+  }
+
+  if (
+    typeof options.limit === "number" &&
+    Number.isFinite(options.limit) &&
+    options.limit > 0
+  ) {
+    filter.limit = Math.floor(options.limit);
+  }
+
+  if (typeof options.since === "number" && Number.isFinite(options.since)) {
+    filter.since = Math.floor(options.since);
+  }
+
+  if (typeof options.until === "number" && Number.isFinite(options.until)) {
+    filter.until = Math.floor(options.until);
+  }
+
+  return { descriptor, filters: [filter] };
+}
+
+function flattenListResults(input) {
+  if (!Array.isArray(input)) {
+    return [];
+  }
+
+  const flat = [];
+  for (const chunk of input) {
+    if (Array.isArray(chunk)) {
+      for (const item of chunk) {
+        if (item && typeof item === "object") {
+          flat.push(item);
+        }
+      }
+    } else if (chunk && typeof chunk === "object") {
+      flat.push(chunk);
+    }
+  }
+  return flat;
+}
+
+function isVideoCommentEvent(event, descriptor) {
+  if (!event || typeof event !== "object") {
+    return false;
+  }
+
+  if (Number(event.kind) !== COMMENT_EVENT_KIND) {
+    return false;
+  }
+
+  const tags = Array.isArray(event.tags) ? event.tags : [];
+  let hasEventTag = false;
+  let hasDefinitionTag = false;
+  let hasParentTag = !descriptor.parentCommentId;
+
+  for (const tag of tags) {
+    if (!Array.isArray(tag) || tag.length < 2) {
+      continue;
+    }
+    const [name, value] = tag;
+    if (name === "e" && typeof value === "string") {
+      if (value === descriptor.videoEventId) {
+        hasEventTag = true;
+      }
+      if (descriptor.parentCommentId && value === descriptor.parentCommentId) {
+        hasParentTag = true;
+      }
+    } else if (name === "a" && typeof value === "string") {
+      if (value === descriptor.videoDefinitionAddress) {
+        hasDefinitionTag = true;
+      }
+    }
+  }
+
+  return hasEventTag && hasDefinitionTag && hasParentTag;
+}
+
+export async function publishComment(
+  client,
+  targetInput,
+  options = {},
+  {
+    resolveActiveSigner,
+    shouldRequestExtensionPermissions,
+    signEventWithPrivateKey,
+    DEFAULT_NIP07_PERMISSION_METHODS,
+  } = {},
+) {
+  if (!client?.pool) {
+    return { ok: false, error: "nostr-uninitialized" };
+  }
+
+  const descriptor = normalizeCommentTarget(targetInput, options);
+  if (!descriptor) {
+    return { ok: false, error: "invalid-target" };
+  }
+
+  const actorPubkey = await client.ensureSessionActor();
+  if (!actorPubkey) {
+    return { ok: false, error: "missing-actor" };
+  }
+
+  const createdAt =
+    typeof options.created_at === "number" && options.created_at > 0
+      ? Math.floor(options.created_at)
+      : Math.floor(Date.now() / 1000);
+
+  const additionalTags = Array.isArray(options.additionalTags)
+    ? options.additionalTags.filter(
+        (tag) => Array.isArray(tag) && typeof tag[0] === "string",
+      )
+    : [];
+
+  let content = "";
+  if (typeof options.content === "string") {
+    content = options.content;
+  } else if (
+    options.content &&
+    typeof options.content === "object" &&
+    !Array.isArray(options.content)
+  ) {
+    try {
+      content = JSON.stringify(options.content);
+    } catch (error) {
+      devLogger.warn("[nostr] Failed to serialize comment content:", error);
+      content = "";
+    }
+  } else if (options.content !== undefined && options.content !== null) {
+    content = String(options.content);
+  }
+
+  const event = buildCommentEvent({
+    pubkey: actorPubkey,
+    created_at: createdAt,
+    videoEventId: descriptor.videoEventId,
+    videoEventRelay: descriptor.videoEventRelay,
+    videoDefinitionAddress: descriptor.videoDefinitionAddress,
+    videoDefinitionRelay: descriptor.videoDefinitionRelay,
+    parentCommentId: descriptor.parentCommentId,
+    parentCommentRelay: descriptor.parentCommentRelay,
+    threadParticipantPubkey: descriptor.threadParticipantPubkey,
+    threadParticipantRelay: descriptor.threadParticipantRelay,
+    additionalTags,
+    content,
+  });
+
+  let signedEvent = null;
+
+  const normalizedActor =
+    typeof actorPubkey === "string" ? actorPubkey.toLowerCase() : "";
+  const normalizedLogged =
+    typeof client.pubkey === "string" ? client.pubkey.toLowerCase() : "";
+
+  const resolveSignerFn =
+    typeof resolveActiveSigner === "function" ? resolveActiveSigner : null;
+  const signer = resolveSignerFn ? resolveSignerFn(actorPubkey) : null;
+
+  const canUseActiveSigner =
+    normalizedActor &&
+    normalizedActor === normalizedLogged &&
+    signer &&
+    typeof signer.signEvent === "function";
+
+  if (canUseActiveSigner) {
+    let permissionResult = { ok: true };
+    const shouldRequestPermissions =
+      typeof shouldRequestExtensionPermissions === "function"
+        ? shouldRequestExtensionPermissions(signer)
+        : false;
+
+    if (shouldRequestPermissions) {
+      permissionResult = await client.ensureExtensionPermissions(
+        DEFAULT_NIP07_PERMISSION_METHODS,
+      );
+    }
+
+    if (permissionResult.ok) {
+      try {
+        signedEvent = await signer.signEvent(event);
+      } catch (error) {
+        userLogger.warn(
+          "[nostr] Failed to sign comment event with active signer:",
+          error,
+        );
+        return { ok: false, error: "signing-failed", details: error };
+      }
+    } else {
+      userLogger.warn(
+        "[nostr] Active signer permissions missing; signing comment with session key.",
+        permissionResult.error,
+      );
+    }
+  }
+
+  if (!signedEvent) {
+    if (typeof signEventWithPrivateKey !== "function") {
+      return { ok: false, error: "signing-unavailable" };
+    }
+    try {
+      if (!client.sessionActor || client.sessionActor.pubkey !== actorPubkey) {
+        await client.ensureSessionActor(true);
+      }
+      if (!client.sessionActor || client.sessionActor.pubkey !== actorPubkey) {
+        throw new Error("session-actor-mismatch");
+      }
+      signedEvent = signEventWithPrivateKey(
+        event,
+        client.sessionActor.privateKey,
+      );
+    } catch (error) {
+      userLogger.warn("[nostr] Failed to sign comment event with session key:", error);
+      return { ok: false, error: "signing-failed", details: error };
+    }
+  }
+
+  const relayList = sanitizeRelayList(options.relays, client.relays);
+
+  const publishResults = await Promise.all(
+    relayList.map((url) => publishEventToRelay(client.pool, url, signedEvent)),
+  );
+
+  const acceptedRelays = publishResults
+    .filter((result) => result.success)
+    .map((result) => result.url)
+    .filter((url) => typeof url === "string" && url);
+
+  const success = acceptedRelays.length > 0;
+
+  if (success) {
+    devLogger.info(
+      `[nostr] Comment event accepted by ${acceptedRelays.length} relay(s):`,
+      acceptedRelays.join(", "),
+    );
+  } else {
+    userLogger.warn("[nostr] Comment event rejected by relays:", publishResults);
+  }
+
+  return {
+    ok: success,
+    event: signedEvent,
+    results: publishResults,
+    acceptedRelays,
+  };
+}
+
+export async function listVideoComments(client, targetInput, options = {}) {
+  const pool = client?.pool;
+  const canQueryPool = pool && typeof pool.list === "function";
+
+  if (!canQueryPool) {
+    devLogger.warn("[nostr] Unable to list video comments: pool missing.");
+    return [];
+  }
+
+  let descriptor;
+  let filters;
+  try {
+    ({ descriptor, filters } = createVideoCommentFilters(targetInput, options));
+  } catch (error) {
+    devLogger.warn("[nostr] Failed to build comment filters:", error);
+    return [];
+  }
+
+  const relayList = sanitizeRelayList(options.relays, client.relays);
+
+  let rawResults;
+  try {
+    rawResults = await pool.list(relayList, filters);
+  } catch (error) {
+    devLogger.warn("[nostr] Failed to list video comments:", error);
+    return [];
+  }
+
+  const flattened = flattenListResults(rawResults);
+  const dedupe = new Map();
+  const order = [];
+
+  for (const event of flattened) {
+    if (!isVideoCommentEvent(event, descriptor)) {
+      continue;
+    }
+
+    const eventId = typeof event.id === "string" ? event.id : null;
+    if (!eventId) {
+      order.push({ type: "raw", event });
+      continue;
+    }
+
+    const existing = dedupe.get(eventId);
+    if (!existing) {
+      dedupe.set(eventId, event);
+      order.push({ type: "id", key: eventId });
+      continue;
+    }
+
+    const existingCreated = Number.isFinite(existing?.created_at)
+      ? existing.created_at
+      : 0;
+    const incomingCreated = Number.isFinite(event.created_at)
+      ? event.created_at
+      : 0;
+    if (incomingCreated > existingCreated) {
+      dedupe.set(eventId, event);
+    }
+  }
+
+  return order
+    .map((entry) => {
+      if (!entry) {
+        return null;
+      }
+      if (entry.type === "raw") {
+        return entry.event || null;
+      }
+      if (entry.type === "id") {
+        return dedupe.get(entry.key) || null;
+      }
+      return null;
+    })
+    .filter(Boolean);
+}
+
+export function subscribeVideoComments(client, targetInput, options = {}) {
+  const pool = client?.pool;
+  const canSubscribe = pool && typeof pool.sub === "function";
+
+  if (!canSubscribe) {
+    devLogger.warn("[nostr] Unable to subscribe to video comments: pool missing.");
+    return () => {};
+  }
+
+  let descriptor;
+  let filters;
+  try {
+    ({ descriptor, filters } = createVideoCommentFilters(targetInput, options));
+  } catch (error) {
+    devLogger.warn("[nostr] Failed to build comment subscription filters:", error);
+    return () => {};
+  }
+
+  const relayList = sanitizeRelayList(options.relays, client.relays);
+  const onEvent = typeof options.onEvent === "function" ? options.onEvent : null;
+
+  let subscription;
+  try {
+    subscription = pool.sub(relayList, filters);
+  } catch (error) {
+    devLogger.warn("[nostr] Failed to open video comment subscription:", error);
+    return () => {};
+  }
+
+  if (onEvent && subscription && typeof subscription.on === "function") {
+    try {
+      subscription.on("event", (event) => {
+        if (isVideoCommentEvent(event, descriptor)) {
+          try {
+            onEvent(event);
+          } catch (handlerError) {
+            devLogger.warn("[nostr] Comment subscription handler threw:", handlerError);
+          }
+        }
+      });
+    } catch (error) {
+      devLogger.warn("[nostr] Failed to attach comment subscription handler:", error);
+    }
+  }
+
+  const originalUnsub =
+    subscription && typeof subscription.unsub === "function"
+      ? subscription.unsub.bind(subscription)
+      : null;
+
+  let unsubscribed = false;
+  return () => {
+    if (unsubscribed) {
+      return;
+    }
+    unsubscribed = true;
+    if (originalUnsub) {
+      try {
+        originalUnsub();
+      } catch (error) {
+        devLogger.warn("[nostr] Failed to unsubscribe from video comments:", error);
+      }
+    }
+  };
+}
+
+export const __testExports = {
+  normalizeCommentTarget,
+  createVideoCommentFilters,
+  isVideoCommentEvent,
+};
diff --git a/js/nostr/index.js b/js/nostr/index.js
index 0bf16db5..11fdab61 100644
--- a/js/nostr/index.js
+++ b/js/nostr/index.js
@@ -57,3 +57,9 @@ export {
 } from "./viewEvents.js";
 
 export { publishVideoReaction } from "./reactionEvents.js";
+export {
+  COMMENT_EVENT_KIND,
+  publishComment,
+  listVideoComments,
+  subscribeVideoComments,
+} from "./commentEvents.js";
diff --git a/tests/nostr/comment-events.test.mjs b/tests/nostr/comment-events.test.mjs
new file mode 100644
index 00000000..c08693c2
--- /dev/null
+++ b/tests/nostr/comment-events.test.mjs
@@ -0,0 +1,356 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+
+import {
+  COMMENT_EVENT_KIND,
+  publishComment,
+  listVideoComments,
+  subscribeVideoComments,
+} from "../../js/nostr/commentEvents.js";
+
+function createMockClient({
+  actorPubkey = "actor-pubkey",
+  sessionPrivateKey = "session-private",
+  relays = ["wss://primary"],
+  publishResults = [],
+} = {}) {
+  const publishCalls = [];
+  const pool = {
+    publish(urls, event) {
+      publishCalls.push({ urls, event });
+      const result = publishResults.shift();
+      return {
+        on(name, handler) {
+          if (name === "ok" && (!result || result.success !== false)) {
+            handler();
+          }
+          if (name === "failed" && result && result.success === false) {
+            handler(result.error || new Error("publish failed"));
+          }
+        },
+      };
+    },
+    list: async () => [],
+    sub: () => ({ on() {}, unsub() {} }),
+  };
+
+  const ensureSessionActorCalls = [];
+  const client = {
+    pool,
+    relays,
+    pubkey: actorPubkey,
+    sessionActor: {
+      pubkey: actorPubkey,
+      privateKey: sessionPrivateKey,
+    },
+    ensureSessionActor: async (forceRefresh = false) => {
+      ensureSessionActorCalls.push(forceRefresh);
+      if (forceRefresh && !client.sessionActor) {
+        client.sessionActor = {
+          pubkey: actorPubkey,
+          privateKey: sessionPrivateKey,
+        };
+      }
+      return actorPubkey;
+    },
+    ensureExtensionPermissions: async () => ({ ok: true }),
+  };
+
+  return { client, pool, publishCalls, ensureSessionActorCalls };
+}
+
+function buildCommentEventTags(event) {
+  return Array.isArray(event?.tags)
+    ? event.tags.map((tag) => Array.isArray(tag) ? [...tag] : tag)
+    : [];
+}
+
+test("publishComment prefers active signer when available", async () => {
+  const {
+    client,
+    publishCalls,
+  } = createMockClient({
+    relays: ["wss://relay.one", "wss://relay.two"],
+  });
+
+  const signerCalls = [];
+  const signer = {
+    type: "extension",
+    pubkey: client.pubkey,
+    async signEvent(event) {
+      signerCalls.push(event);
+      return { ...event, id: "signed-by-active" };
+    },
+  };
+
+  let privateKeySignCalls = 0;
+
+  const result = await publishComment(
+    client,
+    {
+      videoEventId: "video-event-id",
+      videoEventRelay: "wss://video-relay",
+      videoDefinitionAddress: "30078:deadbeef:clip",
+      videoDefinitionRelay: "wss://definition-relay",
+      parentCommentId: "parent-comment-id",
+      threadParticipantPubkey: "thread-participant",
+    },
+    {
+      content: "Hello world",
+      relays: ["wss://custom"],
+    },
+    {
+      resolveActiveSigner: () => signer,
+      shouldRequestExtensionPermissions: () => true,
+      signEventWithPrivateKey: () => {
+        privateKeySignCalls += 1;
+        return null;
+      },
+      DEFAULT_NIP07_PERMISSION_METHODS: ["signEvent"],
+    },
+  );
+
+  assert.equal(result.ok, true, "publish should succeed when relay accepts the event");
+  assert.deepEqual(
+    result.acceptedRelays,
+    ["wss://custom"],
+    "accepted relays should reflect the sanitized relay list",
+  );
+  assert.equal(
+    publishCalls.length,
+    1,
+    "exactly one publish call should be issued",
+  );
+  assert.deepEqual(
+    publishCalls[0].urls,
+    ["wss://custom"],
+    "publish should target the caller supplied relays",
+  );
+
+  assert.equal(privateKeySignCalls, 0, "session key signing should be skipped when active signer succeeds");
+  assert.equal(signerCalls.length, 1, "active signer should sign the event once");
+
+  const eventTags = buildCommentEventTags(signerCalls[0]);
+  const eTags = eventTags.filter((tag) => Array.isArray(tag) && tag[0] === "e");
+  const aTags = eventTags.filter((tag) => Array.isArray(tag) && tag[0] === "a");
+  assert.deepEqual(
+    eTags,
+    [
+      ["e", "video-event-id", "wss://video-relay"],
+      ["e", "parent-comment-id"],
+    ],
+    "comment event should include both video and parent pointers",
+  );
+  assert.deepEqual(
+    aTags,
+    [["a", "30078:deadbeef:clip", "wss://definition-relay"]],
+    "comment event should target the video definition via #a tag",
+  );
+});
+
+test("publishComment falls back to session signer when active signer is missing", async () => {
+  const {
+    client,
+    publishCalls,
+    ensureSessionActorCalls,
+  } = createMockClient();
+
+  client.sessionActor = null;
+
+  let privateKeySignCalls = 0;
+  const signEventWithPrivateKey = (event, key) => {
+    privateKeySignCalls += 1;
+    assert.equal(key, "session-private", "session key should be used when rehydrated");
+    return { ...event, id: "signed-by-session" };
+  };
+
+  const result = await publishComment(
+    client,
+    {
+      videoEventId: "event-1",
+      videoDefinitionAddress: "30078:abc:def",
+    },
+    { content: "Fallback" },
+    {
+      resolveActiveSigner: () => null,
+      shouldRequestExtensionPermissions: () => false,
+      signEventWithPrivateKey,
+      DEFAULT_NIP07_PERMISSION_METHODS: [],
+    },
+  );
+
+  assert.equal(result.ok, true, "publish should succeed with session signer");
+  assert.equal(privateKeySignCalls, 1, "session signing should occur exactly once");
+  assert.equal(
+    ensureSessionActorCalls.includes(true),
+    true,
+    "ensureSessionActor should be invoked with force refresh",
+  );
+  assert.equal(publishCalls.length, 1, "publish should still occur once");
+});
+
+test("listVideoComments builds filters with both #e and #a tags", async () => {
+  const matchingEventLatest = {
+    id: "comment-2",
+    kind: COMMENT_EVENT_KIND,
+    created_at: 1700000200,
+    tags: [
+      ["e", "video-1"],
+      ["a", "30078:author:clip"],
+      ["e", "parent-1"],
+    ],
+  };
+
+  const matchingEventOlder = {
+    id: "comment-2",
+    kind: COMMENT_EVENT_KIND,
+    created_at: 1690000000,
+    tags: [
+      ["e", "video-1"],
+      ["a", "30078:author:clip"],
+      ["e", "parent-1"],
+    ],
+  };
+
+  const otherEvent = {
+    id: "comment-3",
+    kind: COMMENT_EVENT_KIND,
+    created_at: 1700000100,
+    tags: [["e", "video-1"]],
+  };
+
+  const {
+    client,
+    pool,
+  } = createMockClient();
+
+  let receivedFilters = null;
+  pool.list = async (relays, filters) => {
+    receivedFilters = { relays, filters };
+    return [[matchingEventLatest, matchingEventOlder, otherEvent]];
+  };
+
+  const events = await listVideoComments(
+    client,
+    {
+      videoEventId: "video-1",
+      videoDefinitionAddress: "30078:author:clip",
+      parentCommentId: "parent-1",
+    },
+    { relays: ["wss://history"], since: 1700000000, limit: 10 },
+  );
+
+  assert.ok(Array.isArray(events), "listing should produce an array");
+  assert.equal(events.length, 1, "duplicate ids should be collapsed to the newest instance");
+  assert.equal(events[0].id, "comment-2", "newest event should be retained");
+
+  assert.ok(receivedFilters, "pool.list should receive filters");
+  assert.deepEqual(
+    receivedFilters.relays,
+    ["wss://history"],
+    "list should use caller provided relays",
+  );
+  assert.equal(receivedFilters.filters.length, 1, "exactly one filter should be emitted");
+  const [filter] = receivedFilters.filters;
+  assert.equal(filter.kinds[0], COMMENT_EVENT_KIND, "filter should target comment kind");
+  assert.deepEqual(
+    filter["#e"],
+    ["video-1", "parent-1"],
+    "filter should bind the video and parent ids via #e",
+  );
+  assert.deepEqual(
+    filter["#a"],
+    ["30078:author:clip"],
+    "filter should bind the video definition via #a",
+  );
+  assert.equal(filter.since, 1700000000, "since option should propagate to filter");
+  assert.equal(filter.limit, 10, "limit option should propagate to filter");
+});
+
+test("subscribeVideoComments forwards matching events and cleans up unsubscribe", async () => {
+  const {
+    client,
+    pool,
+  } = createMockClient();
+
+  let handler = null;
+  let unsubCalls = 0;
+  let subscriptionArgs = null;
+  pool.sub = (relays, filters) => {
+    subscriptionArgs = { relays, filters };
+    handler = null;
+    return {
+      on(name, cb) {
+        if (name === "event") {
+          handler = cb;
+        }
+      },
+      unsub() {
+        unsubCalls += 1;
+      },
+      relays,
+      filters,
+    };
+  };
+
+  const receivedEvents = [];
+  const unsubscribe = subscribeVideoComments(
+    client,
+    {
+      videoEventId: "video-1",
+      videoDefinitionAddress: "30078:author:clip",
+      parentCommentId: "parent-1",
+    },
+    {
+      relays: ["wss://live"],
+      onEvent: (event) => {
+        receivedEvents.push(event);
+      },
+    },
+  );
+
+  assert.ok(typeof unsubscribe === "function", "subscribe should return an unsubscribe function");
+  assert.ok(handler, "subscription handler should be registered");
+  assert.ok(subscriptionArgs, "subscription should capture args");
+  assert.deepEqual(
+    subscriptionArgs.relays,
+    ["wss://live"],
+    "subscription should use caller provided relays",
+  );
+  assert.equal(subscriptionArgs.filters.length, 1, "subscription should emit a single filter");
+  const [subFilter] = subscriptionArgs.filters;
+  assert.deepEqual(
+    subFilter["#e"],
+    ["video-1", "parent-1"],
+    "subscription filter should bind video and parent ids",
+  );
+  assert.deepEqual(
+    subFilter["#a"],
+    ["30078:author:clip"],
+    "subscription filter should bind the video definition",
+  );
+
+  handler({
+    id: "comment-accepted",
+    kind: COMMENT_EVENT_KIND,
+    tags: [
+      ["e", "video-1"],
+      ["a", "30078:author:clip"],
+      ["e", "parent-1"],
+    ],
+  });
+
+  handler({
+    id: "comment-rejected",
+    kind: COMMENT_EVENT_KIND,
+    tags: [["e", "video-1"]],
+  });
+
+  assert.equal(receivedEvents.length, 1, "only matching events should reach the callback");
+  assert.equal(receivedEvents[0].id, "comment-accepted", "matching event should be forwarded");
+
+  unsubscribe();
+  unsubscribe();
+
+  assert.equal(unsubCalls, 1, "underlying unsubscribe should only run once");
+});