feat(slack): expose user email in message.author

.changeset/add-author-field-and-scope.md

@@ -0,0 +1,6 @@
+---
+"chat": minor
+"@chat-adapter/slack": minor
+---
+
+Add new field on Author in core types and a new scope for Slack.

examples/nextjs-chat/slack-manifest.yml

@@ -26,6 +26,8 @@ oauth_config:
       - reactions:write
       # User info for display names
       - users:read
+      # Optional: required to fetch user emails (message.author.email)
+      # - users:read.email
 
 settings:
   event_subscriptions:

packages/adapter-slack/README.md

@@ -132,6 +132,8 @@ oauth_config:
       - reactions:read
       - reactions:write
       - users:read
+      # Optional: required only for fetching user emails (message.author.email)
+      # - users:read.email
 
 settings:
   event_subscriptions:
@@ -153,6 +155,8 @@ settings:
   token_rotation_enabled: false
 ```
 
+> **Note on optional scopes**: To fetch user emails (available on the `email` property of `message.author`), you must add `users:read.email` to the `bot` scopes above. Existing app installations will need to be re-installed to grant this new scope if you add it later.
+
 4. Replace `https://your-domain.com/api/webhooks/slack` with your deployed webhook URL
 5. Click **Create**
 

packages/adapter-slack/src/index.test.ts

@@ -3107,6 +3107,102 @@ describe("fetchMessage", () => {
 
     expect(msg).toBeNull();
   });
+  it("populates author email when available", async () => {
+    const adapter = createSlackAdapter({
+      botToken: "xoxb-test-token",
+      signingSecret: secret,
+      logger: mockLogger,
+      botUserId: "U_BOT",
+    });
+
+    mockClientMethod(
+      adapter,
+      "conversations.replies",
+      vi.fn().mockResolvedValue({
+        ok: true,
+        messages: [
+          {
+            type: "message",
+            user: "U1",
+            text: "Email test",
+            ts: "1234567890.123456",
+            channel: "C123",
+          },
+        ],
+      })
+    );
+
+    mockClientMethod(
+      adapter,
+      "users.info",
+      vi.fn().mockResolvedValue({
+        ok: true,
+        user: {
+          name: "user1",
+          real_name: "User One",
+          profile: { email: "user1@example.com" },
+        },
+      })
+    );
+
+    const state = createMockState();
+    await adapter.initialize(createMockChatInstance(state));
+
+    const msg = await adapter.fetchMessage(
+      "slack:C123:1234567890.000000",
+      "1234567890.123456"
+    );
+
+    expect(msg?.author.email).toBe("user1@example.com");
+  });
+  it("sets author email to undefined when Slack profile email is missing", async () => {
+    const adapter = createSlackAdapter({
+      botToken: "xoxb-test-token",
+      signingSecret: secret,
+      logger: mockLogger,
+      botUserId: "U_BOT",
+    });
+
+    mockClientMethod(
+      adapter,
+      "conversations.replies",
+      vi.fn().mockResolvedValue({
+        ok: true,
+        messages: [
+          {
+            type: "message",
+            user: "U1",
+            text: "No email scope",
+            ts: "1234567890.123456",
+            channel: "C123",
+          },
+        ],
+      })
+    );
+
+    mockClientMethod(
+      adapter,
+      "users.info",
+      vi.fn().mockResolvedValue({
+        ok: true,
+        user: {
+          name: "user1",
+          real_name: "User One",
+          profile: {},
+        },
+      })
+    );
+
+    const state = createMockState();
+    await adapter.initialize(createMockChatInstance(state));
+
+    const msg = await adapter.fetchMessage(
+      "slack:C123:1234567890.000000",
+      "1234567890.123456"
+    );
+
+    expect(msg?.author.email).toBeUndefined();
+  });
 });
 
 // ============================================================================

packages/adapter-slack/src/index.ts

@@ -351,6 +351,7 @@ type SlackInteractivePayload =
 /** Cached user info */
 interface CachedUser {
   displayName: string;
+  email?: string;
   realName: string;
 }
 
@@ -700,14 +701,18 @@ export class SlackAdapter implements Adapter<SlackThreadId, unknown> {
    */
   private async lookupUser(
     userId: string
-  ): Promise<{ displayName: string; realName: string }> {
+  ): Promise<{ displayName: string; realName: string; email?: string }> {
     const cacheKey = `slack:user:${userId}`;
 
     // Check cache first (via state adapter for serverless compatibility)
     if (this.chat) {
       const cached = await this.chat.getState().get<CachedUser>(cacheKey);
       if (cached) {
-        return { displayName: cached.displayName, realName: cached.realName };
+        return {
+          displayName: cached.displayName,
+          realName: cached.realName,
+          email: cached.email,
+        };
       }
     }
 
@@ -718,7 +723,7 @@ export class SlackAdapter implements Adapter<SlackThreadId, unknown> {
       const user = result.user as {
         name?: string;
         real_name?: string;
-        profile?: { display_name?: string; real_name?: string };
+        profile?: { display_name?: string; real_name?: string; email?: string };
       };
 
       // Slack user naming: profile.display_name > profile.real_name > real_name > name > userId
@@ -730,14 +735,15 @@ export class SlackAdapter implements Adapter<SlackThreadId, unknown> {
         userId;
       const realName =
         user?.real_name || user?.profile?.real_name || displayName;
+      const email = user?.profile?.email;
 
       // Cache the result via state adapter
       if (this.chat) {
         await this.chat
           .getState()
           .set<CachedUser>(
             cacheKey,
-            { displayName, realName },
+            { displayName, realName, email },
             SlackAdapter.USER_CACHE_TTL_MS
           );
 
@@ -757,8 +763,9 @@ export class SlackAdapter implements Adapter<SlackThreadId, unknown> {
         userId,
         displayName,
         realName,
+        email,
       });
-      return { displayName, realName };
+      return { displayName, realName, email };
     } catch (error) {
       this.logger.warn("Could not fetch user info", { userId, error });
       // Fall back to user ID
@@ -1868,12 +1875,16 @@ export class SlackAdapter implements Adapter<SlackThreadId, unknown> {
     // since Slack events only include the user ID, not the username
     let userName = event.username || "unknown";
     let fullName = event.username || "unknown";
+    let userEmail: string | undefined;
 
     // If we have a user ID but no username, look up the user info
-    if (event.user && !event.username) {
+    if (event.user) {
       const userInfo = await this.lookupUser(event.user);
-      userName = userInfo.displayName;
-      fullName = userInfo.realName;
+      if (!event.username) {
+        userName = userInfo.displayName;
+        fullName = userInfo.realName;
+      }
+      userEmail = userInfo.email;
     }
 
     // Track thread participants for outgoing mention resolution (skip dupes)
@@ -1911,6 +1922,7 @@ export class SlackAdapter implements Adapter<SlackThreadId, unknown> {
         userId: event.user || event.bot_id || "unknown",
         userName,
         fullName,
+        email: userEmail,
         isBot: !!event.bot_id,
         isMe,
       },
@@ -3372,6 +3384,7 @@ export class SlackAdapter implements Adapter<SlackThreadId, unknown> {
         userId: event.user || event.bot_id || "unknown",
         userName,
         fullName,
+        email: undefined,
         isBot: !!event.bot_id,
         isMe,
       },

packages/chat/src/types.ts

@@ -1068,6 +1068,8 @@ export interface RawMessage<TRawMessage = unknown> {
 }
 
 export interface Author {
+  /** Email address (if supported by platform and scopes) */
+  email?: string;
   /** Display name */
   fullName: string;
   /** Whether the author is a bot */