diff --git a/extensions/feishu/src/accounts.ts b/extensions/feishu/src/accounts.ts
index cb531285277..bebd59f8e43 100644
--- a/extensions/feishu/src/accounts.ts
+++ b/extensions/feishu/src/accounts.ts
@@ -53,12 +53,6 @@ export class FeishuSecretRefUnavailableError extends Error {
   }
 }
 
-export function isFeishuSecretRefUnavailableError(
-  error: unknown,
-): error is FeishuSecretRefUnavailableError {
-  return error instanceof FeishuSecretRefUnavailableError;
-}
-
 function resolveFeishuSecretLike(params: {
   value: unknown;
   path: string;
diff --git a/extensions/feishu/src/mention.ts b/extensions/feishu/src/mention.ts
index 9f1e7f7eac2..5a567e3e32c 100644
--- a/extensions/feishu/src/mention.ts
+++ b/extensions/feishu/src/mention.ts
@@ -76,13 +76,6 @@ export function isMentionForwardRequest(event: FeishuMessageEvent, botOpenId?: s
   return hasBotMention && hasOtherMention;
 }
 
-/**
- * Format @mention for text message
- */
-function formatMentionForText(target: MentionTarget): string {
-  return `<at user_id="${target.openId}">${target.name}</at>`;
-}
-
 /**
  * Format @mention for card message (lark_md)
  */
@@ -90,18 +83,6 @@ function formatMentionForCard(target: MentionTarget): string {
   return `<at id=${target.openId}></at>`;
 }
 
-/**
- * Build complete message with @mentions (text format)
- */
-export function buildMentionedMessage(targets: MentionTarget[], message: string): string {
-  if (targets.length === 0) {
-    return message;
-  }
-
-  const mentionParts = targets.map((t) => formatMentionForText(t));
-  return `${mentionParts.join(" ")} ${message}`;
-}
-
 /**
  * Build card content with @mentions (Markdown format)
  */
diff --git a/extensions/feishu/src/send.ts b/extensions/feishu/src/send.ts
index 45309bf1623..2da1319bead 100644
--- a/extensions/feishu/src/send.ts
+++ b/extensions/feishu/src/send.ts
@@ -715,31 +715,6 @@ export async function editMessageFeishu(params: {
   return { messageId, contentType: "post" };
 }
 
-export async function updateCardFeishu(params: {
-  cfg: ClawdbotConfig;
-  messageId: string;
-  card: Record<string, unknown>;
-  accountId?: string;
-}): Promise<void> {
-  const { cfg, messageId, card, accountId } = params;
-  const account = resolveFeishuRuntimeAccount({ cfg, accountId });
-  if (!account.configured) {
-    throw new Error(`Feishu account "${account.accountId}" not configured`);
-  }
-
-  const client = createFeishuClient(account);
-  const content = JSON.stringify(card);
-
-  const response = await client.im.message.patch({
-    path: { message_id: messageId },
-    data: { content },
-  });
-
-  if (response.code !== 0) {
-    throw new Error(`Feishu card update failed: ${response.msg || `code ${response.code}`}`);
-  }
-}
-
 /**
  * Build a Feishu interactive card with markdown content.
  * Cards render markdown properly (code blocks, tables, links, etc.)