Turn Discord mic processing off for TTS playback

poc/src/control-bridge.ts

@@ -484,6 +484,34 @@ function buildServer(): McpServer {
             jsonText(await pacedVoice(() => requireCore().voiceJoin(channelId, mute ?? true)))
     );
 
+    server.registerTool(
+        "set_voice_processing",
+        {
+            description:
+                "Read or change Discord's microphone processing. Defaults turn noise suppression, " +
+                "echo cancellation, automatic gain control, and noise cancellation off, which stops " +
+                "the call from ramping in and clipping the first words of TTS. Voice joins already " +
+                "do this automatically.",
+            inputSchema: {
+                noiseSuppression: z.boolean().optional(),
+                echoCancellation: z.boolean().optional(),
+                automaticGainControl: z.boolean().optional(),
+                noiseCancellation: z.boolean().optional(),
+                inputVolume: z.number().min(0).max(200).optional().describe("Discord input volume percent")
+            }
+        },
+        async ({ noiseSuppression, echoCancellation, automaticGainControl, noiseCancellation, inputVolume }) =>
+            jsonText(
+                await requireCore().voiceProcessing({
+                    ...(noiseSuppression !== undefined ? { noiseSuppression } : {}),
+                    ...(echoCancellation !== undefined ? { echoCancellation } : {}),
+                    ...(automaticGainControl !== undefined ? { automaticGainControl } : {}),
+                    ...(noiseCancellation !== undefined ? { noiseCancellation } : {}),
+                    ...(inputVolume !== undefined ? { inputVolume } : {})
+                })
+            )
+    );
+
     server.registerTool(
         "voice_leave",
         {

poc/src/core-client.ts

@@ -216,6 +216,19 @@ export class CoreClient {
         return this.request("voice.devices");
     }
 
+    /** Read/turn off Discord's mic processing gates (noise suppression, AGC, echo). */
+    async voiceProcessing(
+        settings: {
+            noiseSuppression?: boolean;
+            echoCancellation?: boolean;
+            automaticGainControl?: boolean;
+            noiseCancellation?: boolean;
+            inputVolume?: number;
+        } = {}
+    ) {
+        return this.request("voice.processing", settings);
+    }
+
     async voiceSetDevices(inputDeviceId?: string, outputDeviceId?: string) {
         return this.request("voice.setDevices", {
             ...(inputDeviceId ? { inputDeviceId } : {}),

poc/src/mock-core.ts

@@ -190,6 +190,15 @@ function handle(action: string | undefined, params: any) {
             userVolumes[userId] = volume;
             return { userId, volume, outputVolume };
         }
+        case "voice.processing":
+            return {
+                noiseSuppression: false,
+                echoCancellation: false,
+                automaticGainControl: false,
+                noiseCancellation: false,
+                inputVolume: null
+            };
+
         case "voice.setDevices":
             return { inputDeviceId: params?.inputDeviceId ?? null, outputDeviceId: params?.outputDeviceId ?? null };
         case "user.search": {