fix: canonicalize discord pluralkit inbound ids

CHANGELOG.md

@@ -41,6 +41,7 @@ Docs: https://docs.openclaw.ai
 - Discord: allow explicitly configured ack reactions in tool-only guild channels while keeping automatic lifecycle/status reactions suppressed. Fixes #74922. Thanks @samvilian and @BlueBirdBack.
 - Discord: preserve attachment and sticker filenames when saving inbound media, so agents can see human-readable file names instead of only UUID-based paths. Fixes #59744. Thanks @xela92 and @rockcent.
 - Discord: preserve non-ASCII channel names in session display labels while keeping allowlist matching on the existing ASCII slug contract. Thanks @swjeong9.
+- Discord/PluralKit: canonicalize proxied webhook turns to the original Discord message id for inbound dedupe, while preserving the proxy message id for reply routing. Thanks @acgh213.
 - Gateway/diagnostics: include a bounded redacted startup error message in stability bundles, so crash-loop reports identify the failing plugin or contract without exposing secrets. Refs #75797. Thanks @ymebosma.
 - Gateway/pricing: abort in-flight model pricing catalog fetches when Gateway shutdown stops the refresh loop, and avoid post-stop cache writes or refresh timers. Fixes #72208. Thanks @rzcq.
 - Codex/app-server: make startup retry cleanup ownership-aware so concurrent Codex lanes cannot close another lane's freshly restarted shared app-server client. Thanks @vincentkoc.

extensions/discord/src/monitor/message-handler.context.ts

@@ -52,6 +52,7 @@ export async function buildDiscordMessageProcessContext(params: {
     message,
     author,
     sender,
+    canonicalMessageId,
     data,
     client,
     channelInfo,
@@ -323,7 +324,10 @@ export async function buildDiscordMessageProcessContext(params: {
     Provider: "discord" as const,
     Surface: "discord" as const,
     WasMentioned: ctx.effectiveWasMentioned,
-    MessageSid: message.id,
+    MessageSid: canonicalMessageId ?? message.id,
+    ...(canonicalMessageId && canonicalMessageId !== message.id
+      ? { MessageSidFull: message.id }
+      : {}),
     ReplyToId: filteredReplyContext?.id,
     ReplyToBody: filteredReplyContext?.body,
     ReplyToSender: filteredReplyContext?.sender,

extensions/discord/src/monitor/message-handler.preflight-pluralkit.ts

@@ -4,13 +4,12 @@ import type { DiscordMessageEvent } from "./message-handler.preflight.types.js";
 
 export async function resolveDiscordPreflightPluralKitInfo(params: {
   message: DiscordMessageEvent["message"];
-  webhookId?: string | null;
   config?: NonNullable<
     NonNullable<import("openclaw/plugin-sdk/config-types").OpenClawConfig["channels"]>["discord"]
   >["pluralkit"];
   abortSignal?: AbortSignal;
 }): Promise<Awaited<ReturnType<typeof import("../pluralkit.js").fetchPluralKitMessageInfo>>> {
-  if (!params.config?.enabled || params.webhookId) {
+  if (!params.config?.enabled) {
     return null;
   }
   try {

extensions/discord/src/monitor/message-handler.preflight.test.ts

@@ -3,9 +3,13 @@ import { ChannelType } from "../internal/discord.js";
 import { createPartialDiscordChannelWithThrowingGetters } from "../test-support/partial-channel.js";
 
 const transcribeFirstAudioMock = vi.hoisted(() => vi.fn());
+const fetchPluralKitMessageInfoMock = vi.hoisted(() => vi.fn());
 const resolveDiscordDmCommandAccessMock = vi.hoisted(() => vi.fn());
 const handleDiscordDmCommandDecisionMock = vi.hoisted(() => vi.fn(async () => {}));
 
+vi.mock("../pluralkit.js", () => ({
+  fetchPluralKitMessageInfo: (...args: unknown[]) => fetchPluralKitMessageInfoMock(...args),
+}));
 vi.mock("./preflight-audio.runtime.js", () => ({
   transcribeFirstAudio: transcribeFirstAudioMock,
 }));
@@ -45,6 +49,10 @@ beforeAll(async () => {
     await import("./thread-bindings.js"));
 });
 
+beforeEach(() => {
+  fetchPluralKitMessageInfoMock.mockReset();
+});
+
 function createThreadBinding(
   overrides?: Partial<import("openclaw/plugin-sdk/conversation-runtime").SessionBindingRecord>,
 ) {
@@ -717,6 +725,77 @@ describe("preflightDiscordMessage", () => {
     expect(result).toBeNull();
   });
 
+  it("canonicalizes PluralKit webhook messages to the original Discord message id", async () => {
+    fetchPluralKitMessageInfoMock.mockResolvedValue({
+      id: "proxy-456",
+      original: "orig-123",
+      member: { id: "member-1", name: "Echo" },
+      system: { id: "system-1", name: "System" },
+    });
+
+    const result = await runGuildPreflight({
+      channelId: "c1",
+      guildId: "g1",
+      message: createDiscordMessage({
+        id: "proxy-456",
+        channelId: "c1",
+        content: "<@openclaw-bot> hello",
+        webhookId: "pluralkit-webhook-1",
+        author: {
+          id: "webhook-author",
+          bot: true,
+          username: "PluralKit",
+        },
+        mentionedUsers: [{ id: "openclaw-bot" }],
+      }),
+      discordConfig: {
+        pluralkit: { enabled: true },
+      } as DiscordConfig,
+    });
+
+    expect(fetchPluralKitMessageInfoMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        messageId: "proxy-456",
+        config: expect.objectContaining({ enabled: true }),
+      }),
+    );
+    expect(result).not.toBeNull();
+    expect(result?.sender.isPluralKit).toBe(true);
+    expect(result?.canonicalMessageId).toBe("orig-123");
+  });
+
+  it("skips PluralKit lookup for bound-thread webhook echoes", async () => {
+    const threadBinding = createThreadBinding({
+      targetKind: "session",
+      targetSessionKey: "agent:main:acp:discord-thread-1",
+    });
+    const threadId = "thread-webhook-pk-echo-1";
+    const parentId = "channel-parent-webhook-pk-echo-1";
+
+    const result = await runThreadBoundPreflight({
+      threadId,
+      parentId,
+      threadBinding,
+      message: createDiscordMessage({
+        id: "m-webhook-pk-echo-1",
+        channelId: threadId,
+        content: "proxied user message",
+        webhookId: "pluralkit-webhook-1",
+        author: {
+          id: "relay-bot-1",
+          bot: true,
+          username: "Proxy",
+        },
+      }),
+      discordConfig: {
+        pluralkit: { enabled: true },
+      } as DiscordConfig,
+    });
+
+    expect(result).toBeNull();
+    expect(fetchPluralKitMessageInfoMock).not.toHaveBeenCalled();
+  });
+
   it("bypasses mention gating in bound threads for allowed bot senders", async () => {
     const threadBinding = createThreadBinding();
     const threadId = "thread-bot-focus";

extensions/discord/src/monitor/message-handler.preflight.ts

@@ -121,28 +121,6 @@ export async function preflightDiscordMessage(
 
   const pluralkitConfig = params.discordConfig?.pluralkit;
   const webhookId = resolveDiscordWebhookId(message);
-  const pluralkitInfo = await resolveDiscordPreflightPluralKitInfo({
-    message,
-    webhookId,
-    config: pluralkitConfig,
-    abortSignal: params.abortSignal,
-  });
-  if (isPreflightAborted(params.abortSignal)) {
-    return null;
-  }
-  const sender = resolveDiscordSenderIdentity({
-    author,
-    member: params.data.member,
-    pluralkitInfo,
-  });
-
-  if (author.bot) {
-    if (allowBotsMode === "off" && !sender.isPluralKit) {
-      logVerbose("discord: drop bot message (allowBots=false)");
-      return null;
-    }
-  }
-
   const isGuildMessage = Boolean(params.data.guild_id);
   const channelInfo = await resolveDiscordChannelInfo(params.client, messageChannelId);
   if (isPreflightAborted(params.abortSignal)) {
@@ -189,6 +167,26 @@ export async function preflightDiscordMessage(
     logVerbose(`discord: drop bound-thread bot system message ${message.id}`);
     return null;
   }
+  const pluralkitInfo = await resolveDiscordPreflightPluralKitInfo({
+    message,
+    config: pluralkitConfig,
+    abortSignal: params.abortSignal,
+  });
+  if (isPreflightAborted(params.abortSignal)) {
+    return null;
+  }
+  const sender = resolveDiscordSenderIdentity({
+    author,
+    member: params.data.member,
+    pluralkitInfo,
+  });
+
+  if (author.bot) {
+    if (allowBotsMode === "off" && !sender.isPluralKit) {
+      logVerbose("discord: drop bot message (allowBots=false)");
+      return null;
+    }
+  }
   const data = message === params.data.message ? params.data : { ...params.data, message };
   logDebug(
     `[discord-preflight] channelId=${messageChannelId} guild_id=${params.data.guild_id} channelType=${channelInfo?.type} isGuild=${isGuildMessage} isDM=${isDirectMessage} isGroupDm=${isGroupDm}`,
@@ -639,6 +637,7 @@ export async function preflightDiscordMessage(
     messageChannelId,
     author,
     sender,
+    canonicalMessageId: pluralkitInfo?.original?.trim() || undefined,
     memberRoleIds,
     channelInfo,
     channelName,

extensions/discord/src/monitor/message-handler.preflight.types.ts

@@ -42,6 +42,7 @@ export type DiscordMessagePreflightContext = DiscordMessagePreflightSharedFields
   messageChannelId: string;
   author: User;
   sender: DiscordSenderIdentity;
+  canonicalMessageId?: string;
   memberRoleIds: string[];
 
   channelInfo: DiscordChannelInfo | null;

extensions/discord/src/monitor/message-handler.process.test.ts

@@ -357,6 +357,8 @@ function getLastDispatchCtx():
       CommandBody?: string;
       From?: string;
       MediaTranscribedIndexes?: number[];
+      MessageSid?: string;
+      MessageSidFull?: string;
       MessageThreadId?: string | number;
       ModelParentSessionKey?: string;
       OriginatingTo?: string;
@@ -375,6 +377,8 @@ function getLastDispatchCtx():
           CommandBody?: string;
           From?: string;
           MediaTranscribedIndexes?: number[];
+          MessageSid?: string;
+          MessageSidFull?: string;
           MessageThreadId?: string | number;
           ModelParentSessionKey?: string;
           OriginatingTo?: string;
@@ -925,6 +929,25 @@ describe("processDiscordMessage session routing", () => {
     expect(sendMocks.removeReactionDiscord).not.toHaveBeenCalled();
   });
 
+  it("uses PluralKit original ids for inbound dedupe while preserving the Discord message id", async () => {
+    const ctx = await createBaseContext({
+      canonicalMessageId: "orig-123",
+      message: {
+        id: "proxy-456",
+        channelId: "c1",
+        timestamp: new Date().toISOString(),
+        attachments: [],
+      },
+    });
+
+    await runProcessDiscordMessage(ctx);
+
+    expect(getLastDispatchCtx()).toMatchObject({
+      MessageSid: "orig-123",
+      MessageSidFull: "proxy-456",
+    });
+  });
+
   it("defaults guild replies to message-tool-only source delivery", async () => {
     await runProcessDiscordMessage(
       await createBaseContext({