Deny skill_search on grok and kimi leaf workers

Search is the noisy surface on small models; use_skill stays available so brief-named skills still load.

Author: TheGreatAxios

src/agent/model-family-policy.test.ts

@@ -52,4 +52,39 @@ describe("resolveModelFamilyPolicy", () => {
     expect(kimi.toolOnlyTurnNudgeAt).toBe(base.toolOnlyTurnNudgeAt);
     expect(kimi.subAgentStallTimeoutMs).toBe(base.subAgentStallTimeoutMs);
   });
+
+  test("advertisedToolDeny is empty by default and never contains use_skill", () => {
+    const leaf = resolveModelFamilyPolicy({
+      providerName: "anthropic",
+      model: "claude-opus-4-6",
+      orchestrator: false,
+    });
+    expect(leaf.advertisedToolDeny).toEqual([]);
+    expect(leaf.advertisedToolDeny).not.toContain("use_skill");
+  });
+
+  test("grok and kimi leaves deny skill_search only", () => {
+    for (const input of [
+      { providerName: "xai", model: "grok-4-1-fast-non-reasoning" },
+      { providerName: "moonshot", model: "kimi-k2-0711" },
+    ] as const) {
+      const leaf = resolveModelFamilyPolicy({
+        ...input,
+        orchestrator: false,
+      });
+      expect(leaf.advertisedToolDeny).toEqual(["skill_search"]);
+      expect(leaf.advertisedToolDeny).not.toContain("use_skill");
+    }
+  });
+
+  test("orchestrators keep the full surface on every family", () => {
+    for (const input of [
+      { providerName: "xai", model: "grok-4-1-fast-non-reasoning" },
+      { providerName: "moonshot", model: "kimi-k2-0711" },
+      { providerName: "anthropic", model: "claude-opus-4-6" },
+    ] as const) {
+      const policy = resolveModelFamilyPolicy({ ...input, orchestrator: true });
+      expect(policy.advertisedToolDeny).toEqual([]);
+    }
+  });
 });

src/agent/model-family-policy.ts

@@ -25,6 +25,13 @@ export interface ModelFamilyPolicy {
   subAgentStallTimeoutMs: number;
   /** Grok's finish-bias residual (withhold from orchestrators; see provider-family.ts). */
   applyGrokFinishBias: boolean;
+  /**
+   * Tool names to drop from the advertised wire prefix and the dispatch gate
+   * (CL-7668). Empty by default; grok/kimi leaves deny `skill_search` only and
+   * load brief-named skills straight through `use_skill`, which is never
+   * denied. Orchestrators keep the full surface.
+   */
+  advertisedToolDeny: readonly string[];
 }
 
 const DEFAULT_WRAP_UP_NUDGE_TEXT =
@@ -50,6 +57,7 @@ const DEFAULT_POLICY: Omit<ModelFamilyPolicy, "family"> = {
   wrapUpNudgeText: DEFAULT_WRAP_UP_NUDGE_TEXT,
   subAgentStallTimeoutMs: 5 * 60_000,
   applyGrokFinishBias: false,
+  advertisedToolDeny: [],
 };
 
 // A directly observed 14-turn pure-tool-call session for this family
@@ -67,6 +75,8 @@ const GROK_POLICY: Omit<ModelFamilyPolicy, "family"> = {
   wrapUpNudgeText: GROK_WRAP_UP_NUDGE_TEXT,
   subAgentStallTimeoutMs: DEFAULT_POLICY.subAgentStallTimeoutMs,
   applyGrokFinishBias: true,
+  // Leaf value; the resolver clears it for orchestrators below.
+  advertisedToolDeny: ["skill_search"],
 };
 
 // Kimi (Moonshot) detection ships now so callers can branch on family, but
@@ -92,10 +102,15 @@ export function resolveModelFamilyPolicy(input: {
       return {
         ...policy,
         applyGrokFinishBias: policy.applyGrokFinishBias && !orchestrator,
+        advertisedToolDeny: orchestrator ? [] : policy.advertisedToolDeny,
       };
     }
     case "kimi":
-      return { family, ...KIMI_POLICY };
+      return {
+        family,
+        ...KIMI_POLICY,
+        advertisedToolDeny: orchestrator ? [] : ["skill_search"],
+      };
     default:
       return { family: "default", ...DEFAULT_POLICY };
   }

src/session/assemble-runtime.ts

@@ -48,6 +48,7 @@ import {
   type ToolAvailability,
 } from "../agent/tool-search.js";
 import { normalizeToolDefinitionsForProvider } from "../agent/tool-schema-normalize.js";
+import { resolveModelFamilyPolicy } from "../agent/model-family-policy.js";
 import { createChatDirector, type ChatDirector } from "../agent/director.js";
 import { createDoomLoopCorrectiveNote } from "../agent/doom-loop-note.js";
 import type { Task } from "../agent/tasks.js";
@@ -369,17 +370,39 @@ export function createAdvertisedToolset(args: {
   ];
   const activated = createActivatedToolTracker();
   // Advertise then family-gate wire schemas (kimi gets a non-recursive present).
+  // advertisedToolDeny (CL-7668) drops grok/kimi-leaf skill_search from the
+  // wire prefix and the dispatch gate; orchestrators keep the full surface.
+  // Resolved per call so a live model switch re-gates without a rebuild.
+  // use_skill is never denied — leaves load brief-named skills by exact name.
+  const deniedFor = (provider: {
+    providerName: string;
+    model: string;
+  }): readonly string[] =>
+    resolveModelFamilyPolicy({
+      providerName: provider.providerName,
+      model: provider.model,
+      orchestrator: args.sessionMode === "orchestrator",
+    }).advertisedToolDeny;
   const computeAdvertised = (
     all: readonly ToolDefinition[],
-  ): ToolDefinition[] =>
-    normalizeToolDefinitionsForProvider(
-      advertisedTools(all, activated.list(), prefix),
+  ): ToolDefinition[] => {
+    const provider = args.getProvider();
+    const denied = deniedFor(provider);
+    const gatedPrefix =
+      denied.length === 0
+        ? prefix
+        : prefix.filter((name) => !denied.includes(name));
+    return normalizeToolDefinitionsForProvider(
+      advertisedTools(all, activated.list(), gatedPrefix),
       {
-        ...args.getProvider(),
+        ...provider,
       },
     );
-  const isAdvertised = (name: string): boolean =>
-    prefix.includes(name) || activated.has(name);
+  };
+  const isAdvertised = (name: string): boolean => {
+    if (deniedFor(args.getProvider()).includes(name)) return false;
+    return prefix.includes(name) || activated.has(name);
+  };
   return { activated, computeAdvertised, isAdvertised };
 }