feat: add actions.sendMessage gating to Discord, Slack, Google Chat, Matrix (#4703)

Enables read-only mode for these channels by adding actions.sendMessage
configuration option. When set to false, blocks outbound messages while
still allowing message reception.

Follows the existing Telegram/WhatsApp pattern:
- Add sendMessage?: boolean to channel ActionConfig types
- Check gate in action handler, throw error if disabled
- Default: true (enabled) when not specified

This brings read-only mode support to 6 out of 7 core channels
(Telegram, WhatsApp, Discord, Slack, Google Chat, Matrix).

extensions/googlechat/src/actions.ts

@@ -77,6 +77,11 @@ export const googlechatMessageActions: ChannelMessageActionAdapter = {
     }
 
     if (action === "send") {
+      const actionConfig = account.config.actions ?? (cfg as OpenClawConfig).channels?.["googlechat"]?.actions;
+      const isActionEnabled = createActionGate(actionConfig as Record<string, boolean | undefined>);
+      if (!isActionEnabled("sendMessage")) {
+        throw new Error("Google Chat sendMessage is disabled.");
+      }
       const to = readStringParam(params, "to", { required: true });
       const content = readStringParam(params, "message", {
         required: true,

extensions/matrix/src/actions.ts

@@ -51,6 +51,11 @@ export const matrixMessageActions: ChannelMessageActionAdapter = {
       readStringParam(params, "to", { required: true });
 
     if (action === "send") {
+      const account = resolveMatrixAccount({ cfg: cfg as CoreConfig });
+      const isActionEnabled = createActionGate((cfg as CoreConfig).channels?.matrix?.actions);
+      if (!isActionEnabled("sendMessage")) {
+        throw new Error("Matrix sendMessage is disabled.");
+      }
       const to = readStringParam(params, "to", { required: true });
       const content = readStringParam(params, "message", {
         required: true,

extensions/matrix/src/config-schema.ts

@@ -6,6 +6,7 @@ const allowFromEntry = z.union([z.string(), z.number()]);
 const matrixActionSchema = z
   .object({
     reactions: z.boolean().optional(),
+    sendMessage: z.boolean().optional(),
     messages: z.boolean().optional(),
     pins: z.boolean().optional(),
     memberInfo: z.boolean().optional(),

src/agents/tools/discord-actions-messaging.ts

@@ -222,8 +222,8 @@ export async function handleDiscordMessagingAction(
       });
     }
     case "sendMessage": {
-      if (!isActionEnabled("messages")) {
-        throw new Error("Discord message sends are disabled.");
+      if (!isActionEnabled("sendMessage")) {
+        throw new Error("Discord sendMessage is disabled.");
       }
       const to = readStringParam(params, "to", { required: true });
       const content = readStringParam(params, "content", {

src/agents/tools/slack-actions.ts

@@ -154,6 +154,9 @@ export async function handleSlackAction(
     }
     switch (action) {
       case "sendMessage": {
+        if (!isActionEnabled("sendMessage")) {
+          throw new Error("Slack sendMessage is disabled.");
+        }
         const to = readStringParam(params, "to", { required: true });
         const content = readStringParam(params, "content", { required: true });
         const mediaUrl = readStringParam(params, "mediaUrl");

src/config/types.discord.ts

@@ -55,6 +55,7 @@ export type DiscordGuildEntry = {
 
 export type DiscordActionConfig = {
   reactions?: boolean;
+  sendMessage?: boolean;
   stickers?: boolean;
   polls?: boolean;
   permissions?: boolean;

src/config/types.googlechat.ts

@@ -30,6 +30,7 @@ export type GoogleChatGroupConfig = {
 
 export type GoogleChatActionConfig = {
   reactions?: boolean;
+  sendMessage?: boolean;
 };
 
 export type GoogleChatAccountConfig = {

src/config/types.slack.ts

@@ -48,6 +48,7 @@ export type SlackReactionNotificationMode = "off" | "own" | "all" | "allowlist";
 
 export type SlackActionConfig = {
   reactions?: boolean;
+  sendMessage?: boolean;
   messages?: boolean;
   pins?: boolean;
   search?: boolean;