From 377b06be0dd2f0dd5deda297f991a13438686899 Mon Sep 17 00:00:00 2001
From: Mohamed Boudra <boudra.moha@gmail.com>
Date: Mon, 2 Nov 2026 01:10:56 +0100
Subject: [PATCH] fix(server): an apply reports the options the plugin reset
 along the way

Applying and unsolicited reports now share one conversion from the plugin's
report to a patch, so a key the plugin stops reporting is a removal on both.
---
 .../src/server/agent/plugin-provider.test.ts  | 19 ++++++++++++++++
 .../src/server/agent/plugin-provider.ts       | 22 +++++++++++++------
 2 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/packages/server/src/server/agent/plugin-provider.test.ts b/packages/server/src/server/agent/plugin-provider.test.ts
index ecfcd440b6..e93283c390 100644
--- a/packages/server/src/server/agent/plugin-provider.test.ts
+++ b/packages/server/src/server/agent/plugin-provider.test.ts
@@ -1171,6 +1171,8 @@ describe("PluginAgentClientRegistry", () => {
             }
             if (typeof loud === "boolean") state.loud = loud;
             if (typeof tokenBudget === "number") state.tokenBudget = tokenBudget;
+            // Going loud returns an unrequested token budget to its default, by leaving it out.
+            if (loud === true && tokenBudget === undefined) state.tokenBudget = undefined;
             emitConfig(emit, input.sessionId);
             emit(
               refuseAfterChanging
@@ -1233,6 +1235,23 @@ describe("PluginAgentClientRegistry", () => {
       },
     );
 
+    test.runIf(shape === "controls")(
+      "an apply returns the option the plugin reset along the way as removed",
+      async () => {
+        const { session, events, changeOnItsOwn } = await openStubbornVoiceSession({});
+        changeOnItsOwn({ tokenBudget: 500 });
+
+        const ended = await session.applyOptions?.({ loud: true });
+
+        expect(ended).toEqual({ token_budget: null });
+        // The apply reports it; the plugin's later identical report is not a second change.
+        expect(eventsOfType(events, "options_changed")).toEqual([
+          { type: "options_changed", provider: "plugin-direct", patch: { token_budget: 500 } },
+        ]);
+        await session.close();
+      },
+    );
+
     test("a rejected apply reports what the plugin moved before refusing, since nothing is stored", async () => {
       const { session, events } = await openStubbornVoiceSession({}, { refuseAfterChanging: true });
 
diff --git a/packages/server/src/server/agent/plugin-provider.ts b/packages/server/src/server/agent/plugin-provider.ts
index e1560d2fa7..60350ec9aa 100644
--- a/packages/server/src/server/agent/plugin-provider.ts
+++ b/packages/server/src/server/agent/plugin-provider.ts
@@ -1462,7 +1462,7 @@ class PluginAgentSession implements AgentSession {
     } finally {
       this.applyingOptions = false;
     }
-    const ended = this.optionDifferences({ ...before, ...settings });
+    const ended = this.optionChanges({ ...before, ...settings });
     for (const [id, value] of Object.entries(settings)) {
       if (value === null) delete this.committedOptions[id];
     }
@@ -1672,14 +1672,22 @@ class PluginAgentSession implements AgentSession {
     this.knownOptions = current;
   }
 
+  /**
+   * What changed against the options `known` to be set: values that differ, and `null` for a key
+   * the plugin no longer reports, which went back to its default.
+   */
+  private optionChanges(known: Readonly<Record<string, JsonValue>>): Record<string, JsonValue> {
+    const patch = this.optionDifferences(known);
+    const current = this.currentOptions();
+    for (const [id, value] of Object.entries(known)) {
+      if (value !== null && !(id in current)) patch[id] = null;
+    }
+    return patch;
+  }
+
   private reportOptionChanges(): AgentStreamEvent[] {
     if (this.applyingOptions) return [];
-    const patch = this.optionDifferences(this.knownOptions);
-    // A key the plugin reported before and no longer reports went back to its default.
-    const current = this.currentOptions();
-    for (const id of Object.keys(this.knownOptions)) {
-      if (!(id in current)) patch[id] = null;
-    }
+    const patch = this.optionChanges(this.knownOptions);
     if (Object.keys(patch).length === 0) return [];
     this.commitOptions();
     return [{ type: "options_changed", provider: this.provider, patch }];