fix(omp): honor hidden custom messages (#2280)

packages/server/src/server/agent/providers/omp/agent.test.ts

@@ -260,6 +260,23 @@ describe("OMP agent client and session", () => {
     expect(omp.completedTurnCount()).toBe(1);
   });
 
+  test("omits live custom messages when display is false", async () => {
+    const omp = new OmpHarness();
+    await omp.start();
+
+    await expect(
+      omp.runPromptAfterExtensionNotice("hello OMP", "model turn completed", false),
+    ).resolves.toMatchObject({ finalText: expect.stringContaining("model turn completed") });
+    expect(omp.timeline()).toEqual([
+      { type: "user_message", text: "hello OMP", messageId: "user-1" },
+      {
+        type: "assistant_message",
+        text: "model turn completed",
+        messageId: "omp-assistant-1",
+      },
+    ]);
+  });
+
   test("does not complete a queued model turn from OMP's local-only hint", async () => {
     const omp = new OmpHarness();
     await omp.start();

packages/server/src/server/agent/providers/omp/agent.ts

@@ -66,6 +66,7 @@ import {
 } from "./provider-config.js";
 export { formatOmpVersionSupport, resolveOmpDiagnosticPaths } from "./provider-config.js";
 import { OmpSubagentCardTracker, type OmpSubagentCardScheduler } from "./subagent-card-tracker.js";
+import { shouldDisplayOmpCustomMessage } from "./custom-message.js";
 import { getUserMessageText } from "./message-history.js";
 import { materializeProviderImage } from "../provider-image-output.js";
 import { OmpCliRuntime } from "./cli-runtime.js";
@@ -2064,15 +2065,17 @@ export class OmpAgentSession implements AgentSession {
       return;
     }
     if (event.message.role === "custom") {
-      const text = getUserMessageText(event.message.content);
+      if (shouldDisplayOmpCustomMessage(event.message)) {
-      if (text) {
+        const text = getUserMessageText(event.message.content);
-        const advisorItem = mapOmpAdvisorMessageToToolCall(event.message, text);
+        if (text) {
-        this.emit({
+          const advisorItem = mapOmpAdvisorMessageToToolCall(event.message, text);
-          type: "timeline",
+          this.emit({
-          provider: this.provider,
+            type: "timeline",
-          turnId,
+            provider: this.provider,
-          item: advisorItem ?? { type: "assistant_message", text },
+            turnId,
-        });
+            item: advisorItem ?? { type: "assistant_message", text },
+          });
+        }
       }
       if (!this.activeTurnHasUserMessage) {
         this.completeTurn(turnId, []);

packages/server/src/server/agent/providers/omp/custom-message.ts

@@ -0,0 +1,7 @@
+import type { OmpAgentMessage } from "./rpc-types.js";
+
+type OmpCustomMessage = Extract<OmpAgentMessage, { role: "custom" }>;
+
+export function shouldDisplayOmpCustomMessage(message: OmpCustomMessage): boolean {
+  return Reflect.get(message, "display") !== false;
+}

packages/server/src/server/agent/providers/omp/history-mapper.test.ts

@@ -209,6 +209,54 @@ describe("OMP history mapper", () => {
     ]);
   });
 
+  test("omits replayed custom messages only when display is false", async () => {
+    await expect(
+      collectHistory(
+        [
+          { role: "user", content: "first prompt" },
+          { role: "custom", content: "hidden reminder", display: false },
+          { role: "custom", content: "visible explicit custom", display: true },
+          { role: "custom", content: "visible legacy custom" },
+          {
+            role: "assistant",
+            content: [{ type: "text", text: "assistant reply" }],
+            responseId: "assistant-history",
+          },
+        ],
+        [{ id: "entry-user-1", text: "first prompt" }],
+      ),
+    ).resolves.toEqual([
+      {
+        type: "timeline",
+        provider: "omp",
+        item: {
+          type: "user_message",
+          text: "first prompt",
+          messageId: "entry-user-1",
+        },
+      },
+      {
+        type: "timeline",
+        provider: "omp",
+        item: { type: "assistant_message", text: "visible explicit custom" },
+      },
+      {
+        type: "timeline",
+        provider: "omp",
+        item: { type: "assistant_message", text: "visible legacy custom" },
+      },
+      {
+        type: "timeline",
+        provider: "omp",
+        item: {
+          type: "assistant_message",
+          text: "assistant reply",
+          messageId: "assistant-history",
+        },
+      },
+    ]);
+  });
+
   test("suppresses replayed raw todo tool calls through the OMP detail hook", async () => {
     await expect(
       collectHistory([

packages/server/src/server/agent/providers/omp/message-history.ts

@@ -1,5 +1,6 @@
 import type { AgentStreamEvent, AgentTimelineItem, ToolCallDetail } from "../../agent-sdk-types.js";
 import type { OmpAgentMessage, OmpImageContent, OmpTextContent } from "./rpc-types.js";
+import { shouldDisplayOmpCustomMessage } from "./custom-message.js";
 import {
   extractTextFromToolResult,
   mapToolDetail,
@@ -117,6 +118,9 @@ export class OmpHistoryMapper {
   private mapCustomMessage(
     message: Extract<OmpAgentMessage, { role: "custom" }>,
   ): AgentStreamEvent[] {
+    if (!shouldDisplayOmpCustomMessage(message)) {
+      return [];
+    }
     const text = getUserMessageText(message.content);
     const mappedEvent = text ? this.hooks.mapCustomMessage?.(message, text, this.provider) : null;
     if (mappedEvent) {

packages/server/src/server/agent/providers/omp/test-utils/omp-harness.ts

@@ -201,16 +201,25 @@ export class OmpHarness {
     return { completion };
   }
 
-  async runPromptAfterExtensionNotice(input: string, output: string): Promise<unknown> {
+  async runPromptAfterExtensionNotice(
+    input: string,
+    output: string,
+    display?: boolean,
+  ): Promise<unknown> {
     const session = this.requireSession();
     const promptStarted = this.omp.latestSession().nextPrompt();
     const run = session.run(input);
     await promptStarted;
     const runtime = this.omp.latestSession();
+    const message = {
+      role: "custom" as const,
+      content: "extension inventory changed",
+      ...(display === undefined ? {} : { display }),
+    };
     runtime.beginTurn();
     runtime.acceptPrompt(input, "user-1");
-    runtime.acceptCustomMessage("extension inventory changed");
+    runtime.emit({ type: "message_end", message });
-    runtime.finishTurn({ role: "custom", content: "extension inventory changed" });
+    runtime.finishTurn(message);
     runtime.beginTurn();
     runtime.streamAssistantText(output);
     runtime.finishTurn();

packages/server/src/server/agent/providers/omp/v17-rpc-compat.test.ts

@@ -1,8 +1,9 @@
 import { describe, expect, test } from "vitest";
 
 import { parseToolArgs, parseToolResult } from "./tool-call-detail.js";
-import { OmpAvailableCommandsUpdateEventSchema } from "./rpc-types.js";
+import { OmpAgentMessageSchema, OmpAvailableCommandsUpdateEventSchema } from "./rpc-types.js";
 import { mapOmpToolDetail } from "./tool-call-mapper.js";
+import { shouldDisplayOmpCustomMessage } from "./custom-message.js";
 
 describe("OMP 17 RPC compatibility", () => {
   test("parses source-attributed command updates", () => {
@@ -16,6 +17,20 @@ describe("OMP 17 RPC compatibility", () => {
     ]);
   });
 
+  test("keeps non-false custom display metadata backward compatible", () => {
+    const message = OmpAgentMessageSchema.parse({
+      role: "custom",
+      content: "visible custom message",
+      display: null,
+    });
+
+    expect(message).toMatchObject({ display: null });
+    if (message.role !== "custom") {
+      throw new Error("Expected a custom OMP message");
+    }
+    expect(shouldDisplayOmpCustomMessage(message)).toBe(true);
+  });
+
   test("maps subscribed custom tool events without assuming built-in names", () => {
     const event = {
       type: "tool_execution_start",