diff --git a/CHANGELOG.md b/CHANGELOG.md
index 478ebd9..fd1e45d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@
 
 ### Fixed
 
+- Restrict Claude authentication slash commands to one-to-one bot DMs instead of accepting other private-channel contexts.
 - Preserve embed titles, descriptions, and URLs in live MCP `read-messages` results.
 - Prevent `!guild` server-memory responses from triggering Discord mentions from stored memory or server names.
 - Verify recent, legacy, and full-text-search history reads before assembling model context; reject symbolic-link files and replaced storage directories.
diff --git a/src/discord/commands/auth.ts b/src/discord/commands/auth.ts
index 310ef31..e235248 100644
--- a/src/discord/commands/auth.ts
+++ b/src/discord/commands/auth.ts
@@ -1,6 +1,7 @@
 import {
     ChatInputCommandInteraction,
     Events,
+    InteractionContextType,
     Message,
     SlashCommandBuilder,
 } from "discord.js";
@@ -22,7 +23,7 @@ export const authCommand = new SlashCommandBuilder()
     .setName("auth")
     .setDescription("Manage Claudify's Claude CLI authentication")
     .setDefaultMemberPermissions(null)
-    .setDMPermission(true)
+    .setContexts(InteractionContextType.BotDM)
     .addSubcommand((subcommand) =>
         subcommand
             .setName("status")
@@ -87,8 +88,11 @@ function safeErrorMessage(error: unknown): string {
         : "Claude authentication failed.";
 }
 
-export function isPrivateAuthContext(guildId: string | null): boolean {
-    return guildId === null;
+export function isPrivateAuthContext(
+    guildId: string | null,
+    context: InteractionContextType | null,
+): boolean {
+    return guildId === null && context === InteractionContextType.BotDM;
 }
 
 export type AuthTextCommand =
@@ -278,7 +282,7 @@ async function handleAuthInteraction(
         return;
     }
 
-    if (!isPrivateAuthContext(interaction.guildId)) {
+    if (!isPrivateAuthContext(interaction.guildId, interaction.context)) {
         await interaction.reply({
             content: "For security, use this command in a private DM.",
             ephemeral: true,
diff --git a/tests/authTextCommand.test.mjs b/tests/authTextCommand.test.mjs
index 98ca592..5bd348b 100644
--- a/tests/authTextCommand.test.mjs
+++ b/tests/authTextCommand.test.mjs
@@ -1,5 +1,6 @@
 import assert from "node:assert/strict";
 import test from "node:test";
+import { InteractionContextType } from "discord.js";
 
 import {
     authCommand,
@@ -7,10 +8,20 @@ import {
     parseAuthTextCommand,
 } from "../build/discord/commands/auth.js";
 
-test("slash auth is available only in private contexts", () => {
-    assert.equal(isPrivateAuthContext(null), true);
-    assert.equal(isPrivateAuthContext("guild-id"), false);
-    assert.equal(authCommand.toJSON().dm_permission, true);
+test("slash auth is available only in bot DMs", () => {
+    assert.equal(
+        isPrivateAuthContext(null, InteractionContextType.BotDM),
+        true,
+    );
+    assert.equal(
+        isPrivateAuthContext(null, InteractionContextType.PrivateChannel),
+        false,
+    );
+    assert.equal(
+        isPrivateAuthContext("guild-id", InteractionContextType.Guild),
+        false,
+    );
+    assert.deepEqual(authCommand.toJSON().contexts, [InteractionContextType.BotDM]);
 });
 
 test("parses private auth text commands", () => {