refactor: centralize slack threading helpers

src/auto-reply/reply/agent-runner.ts

@@ -50,7 +50,7 @@ import {
   shouldSuppressMessagingToolReplies,
 } from "./reply-payloads.js";
 import {
-  createReplyToModeFilter,
+  createReplyToModeFilterForChannel,
   resolveReplyToMode,
 } from "./reply-threading.js";
 import { incrementCompactionCount } from "./session-updates.js";
@@ -260,9 +260,10 @@ export async function runReplyAgent(params: {
     followupRun.run.config,
     replyToChannel,
   );
-  const applyReplyToMode = createReplyToModeFilter(replyToMode, {
-    allowTagsWhenOff: replyToChannel === "slack",
-  });
+  const applyReplyToMode = createReplyToModeFilterForChannel(
+    replyToMode,
+    replyToChannel,
+  );
   const cfg = followupRun.run.config;
 
   if (shouldSteer && isStreaming) {
@@ -718,7 +719,8 @@ export async function runReplyAgent(params: {
 
     const replyTaggedPayloads: ReplyPayload[] = applyReplyThreading({
       payloads: sanitizedPayloads,
-      applyReplyToMode,
+      replyToMode,
+      replyToChannel,
       currentMessageId: sessionCtx.MessageSid,
     })
       .map((payload) => {

src/auto-reply/reply/followup-runner.ts

@@ -19,10 +19,7 @@ import {
   filterMessagingToolDuplicates,
   shouldSuppressMessagingToolReplies,
 } from "./reply-payloads.js";
-import {
-  createReplyToModeFilter,
-  resolveReplyToMode,
-} from "./reply-threading.js";
+import { resolveReplyToMode } from "./reply-threading.js";
 import { isRoutableChannel, routeReply } from "./route-reply.js";
 import { incrementCompactionCount } from "./session-updates.js";
 import type { TypingController } from "./typing.js";
@@ -195,14 +192,12 @@ export function createFollowupRunner(params: {
         (queued.run.messageProvider?.toLowerCase() as
           | OriginatingChannelType
           | undefined);
-      const applyReplyToMode = createReplyToModeFilter(
-        resolveReplyToMode(queued.run.config, replyToChannel),
-        { allowTagsWhenOff: replyToChannel === "slack" },
-      );
+      const replyToMode = resolveReplyToMode(queued.run.config, replyToChannel);
 
       const replyTaggedPayloads: ReplyPayload[] = applyReplyThreading({
         payloads: sanitizedPayloads,
-        applyReplyToMode,
+        replyToMode,
+        replyToChannel,
       });
 
       const dedupedPayloads = filterMessagingToolDuplicates({

src/auto-reply/reply/reply-payloads.ts

@@ -1,9 +1,10 @@
 import { isMessagingToolDuplicate } from "../../agents/pi-embedded-helpers.js";
 import type { MessagingToolSend } from "../../agents/pi-embedded-runner.js";
+import type { ReplyToMode } from "../../config/types.js";
+import type { OriginatingChannelType } from "../templating.js";
 import type { ReplyPayload } from "../types.js";
 import { extractReplyToTag } from "./reply-tags.js";
-
-export type ReplyToModeFilter = (payload: ReplyPayload) => ReplyPayload;
+import { createReplyToModeFilterForChannel } from "./reply-threading.js";
 
 export function applyReplyTagsToPayload(
   payload: ReplyPayload,
@@ -32,10 +33,15 @@ export function isRenderablePayload(payload: ReplyPayload): boolean {
 
 export function applyReplyThreading(params: {
   payloads: ReplyPayload[];
-  applyReplyToMode: ReplyToModeFilter;
+  replyToMode: ReplyToMode;
+  replyToChannel?: OriginatingChannelType;
   currentMessageId?: string;
 }): ReplyPayload[] {
-  const { payloads, applyReplyToMode, currentMessageId } = params;
+  const { payloads, replyToMode, replyToChannel, currentMessageId } = params;
+  const applyReplyToMode = createReplyToModeFilterForChannel(
+    replyToMode,
+    replyToChannel,
+  );
   return payloads
     .map((payload) => applyReplyTagsToPayload(payload, currentMessageId))
     .filter(isRenderablePayload)

src/auto-reply/reply/reply-threading.ts

@@ -38,3 +38,12 @@ export function createReplyToModeFilter(
     return payload;
   };
 }
+
+export function createReplyToModeFilterForChannel(
+  mode: ReplyToMode,
+  channel?: OriginatingChannelType,
+) {
+  return createReplyToModeFilter(mode, {
+    allowTagsWhenOff: channel === "slack",
+  });
+}

src/slack/monitor.ts

@@ -58,7 +58,13 @@ import type { RuntimeEnv } from "../runtime.js";
 import { resolveSlackAccount } from "./accounts.js";
 import { reactSlackMessage } from "./actions.js";
 import { sendMessageSlack } from "./send.js";
+import { resolveSlackThreadTargets } from "./threading.js";
 import { resolveSlackAppToken, resolveSlackBotToken } from "./token.js";
+import type {
+  SlackAppMentionEvent,
+  SlackFile,
+  SlackMessageEvent,
+} from "./types.js";
 
 export type MonitorSlackOpts = {
   botToken?: string;
@@ -71,45 +77,6 @@ export type MonitorSlackOpts = {
   slashCommand?: SlackSlashCommandConfig;
 };
 
-type SlackFile = {
-  id?: string;
-  name?: string;
-  mimetype?: string;
-  size?: number;
-  url_private?: string;
-  url_private_download?: string;
-};
-
-type SlackMessageEvent = {
-  type: "message";
-  user?: string;
-  bot_id?: string;
-  subtype?: string;
-  username?: string;
-  text?: string;
-  ts?: string;
-  thread_ts?: string;
-  event_ts?: string;
-  parent_user_id?: string;
-  channel: string;
-  channel_type?: "im" | "mpim" | "channel" | "group";
-  files?: SlackFile[];
-};
-
-type SlackAppMentionEvent = {
-  type: "app_mention";
-  user?: string;
-  bot_id?: string;
-  username?: string;
-  text?: string;
-  ts?: string;
-  thread_ts?: string;
-  event_ts?: string;
-  parent_user_id?: string;
-  channel: string;
-  channel_type?: "im" | "mpim" | "channel" | "group";
-};
-
 type SlackReactionEvent = {
   type: "reaction_added" | "reaction_removed";
   user?: string;
@@ -1102,12 +1069,10 @@ export async function monitorSlackProvider(opts: MonitorSlackOpts = {}) {
       );
     }
 
-    const incomingThreadTs = message.thread_ts;
-    const eventTs = message.event_ts;
-    const messageTs = message.ts ?? eventTs;
-    const replyThreadTs =
-      incomingThreadTs ?? (replyToMode === "all" ? messageTs : undefined);
-    const statusThreadTs = replyThreadTs ?? messageTs;
+    const { replyThreadTs, statusThreadTs } = resolveSlackThreadTargets({
+      message,
+      replyToMode,
+    });
     let didSetStatus = false;
     const onReplyStart = async () => {
       didSetStatus = true;

src/slack/threading.test.ts

@@ -0,0 +1,48 @@
+import { describe, expect, it } from "vitest";
+
+import { resolveSlackThreadTargets } from "./threading.js";
+
+describe("resolveSlackThreadTargets", () => {
+  it("threads replies when message is already threaded", () => {
+    const { replyThreadTs, statusThreadTs } = resolveSlackThreadTargets({
+      replyToMode: "off",
+      message: {
+        type: "message",
+        channel: "C1",
+        ts: "123",
+        thread_ts: "456",
+      },
+    });
+
+    expect(replyThreadTs).toBe("456");
+    expect(statusThreadTs).toBe("456");
+  });
+
+  it("threads top-level replies when mode is all", () => {
+    const { replyThreadTs, statusThreadTs } = resolveSlackThreadTargets({
+      replyToMode: "all",
+      message: {
+        type: "message",
+        channel: "C1",
+        ts: "123",
+      },
+    });
+
+    expect(replyThreadTs).toBe("123");
+    expect(statusThreadTs).toBe("123");
+  });
+
+  it("keeps status threading even when reply threading is off", () => {
+    const { replyThreadTs, statusThreadTs } = resolveSlackThreadTargets({
+      replyToMode: "off",
+      message: {
+        type: "message",
+        channel: "C1",
+        ts: "123",
+      },
+    });
+
+    expect(replyThreadTs).toBeUndefined();
+    expect(statusThreadTs).toBe("123");
+  });
+});

src/slack/threading.ts

@@ -0,0 +1,15 @@
+import type { ReplyToMode } from "../config/types.js";
+import type { SlackAppMentionEvent, SlackMessageEvent } from "./types.js";
+
+export function resolveSlackThreadTargets(params: {
+  message: SlackMessageEvent | SlackAppMentionEvent;
+  replyToMode: ReplyToMode;
+}) {
+  const incomingThreadTs = params.message.thread_ts;
+  const eventTs = params.message.event_ts;
+  const messageTs = params.message.ts ?? eventTs;
+  const replyThreadTs =
+    incomingThreadTs ?? (params.replyToMode === "all" ? messageTs : undefined);
+  const statusThreadTs = replyThreadTs ?? messageTs;
+  return { replyThreadTs, statusThreadTs };
+}

src/slack/types.ts

@@ -0,0 +1,38 @@
+export type SlackFile = {
+  id?: string;
+  name?: string;
+  mimetype?: string;
+  size?: number;
+  url_private?: string;
+  url_private_download?: string;
+};
+
+export type SlackMessageEvent = {
+  type: "message";
+  user?: string;
+  bot_id?: string;
+  subtype?: string;
+  username?: string;
+  text?: string;
+  ts?: string;
+  thread_ts?: string;
+  event_ts?: string;
+  parent_user_id?: string;
+  channel: string;
+  channel_type?: "im" | "mpim" | "channel" | "group";
+  files?: SlackFile[];
+};
+
+export type SlackAppMentionEvent = {
+  type: "app_mention";
+  user?: string;
+  bot_id?: string;
+  username?: string;
+  text?: string;
+  ts?: string;
+  thread_ts?: string;
+  event_ts?: string;
+  parent_user_id?: string;
+  channel: string;
+  channel_type?: "im" | "mpim" | "channel" | "group";
+};