diff --git a/src/codex/catalog/sync.ts b/src/codex/catalog/sync.ts
index b7ab78cfb8..34a5d34d89 100644
--- a/src/codex/catalog/sync.ts
+++ b/src/codex/catalog/sync.ts
@@ -36,9 +36,9 @@ import { MAIN_CODEX_ACCOUNT_ID } from "../main-account";
 import {
   availableAccountGatedNativeModels,
   isCodexModelEntitlementSnapshotCurrent,
-  resolveCodexModelEntitlements,
   type CodexModelEntitlementSnapshot,
 } from "../model-entitlements";
+import { resolveAdmittedCodexModelEntitlements } from "../model-entitlement-admission";
 
 
 import { CODEX_CUSTOM_MODEL_CATALOG_KIND, CODEX_PROVIDER_MODEL_CATALOG_KIND, activeCodexModelsCachePath, applyCatalogMetadata, applyMultiAgentMode, applyNativeOpenAiContextOverride, applyRoutedCodexToolMode, catalogBackupPathFor, catalogHasRoutedEntries, catalogModelSlug, ensureStrictCatalogFields, findNativeTemplate, findSupportedNativeTemplate, isDefaultCatalogPath, isRoutedModelCompatibilityExcluded, legacyCatalogBackupPath, normalizeRoutedCatalogEntry, normalizeServiceTiers, readCatalog, readCatalogBackup, readCodexCatalogPath, readCodexCatalogPathForHome, readConfiguredAutoReviewModel, readNativeBaseline } from "./parsing";
@@ -1836,7 +1836,7 @@ export async function syncCatalogModels(
       comboOmissions,
       providerModelOutcomes,
     }),
-    resolveCodexModelEntitlements(config),
+    resolveAdmittedCodexModelEntitlements(config),
   ]);
   const committed = withCatalogWriteSerialization(owningCodexHome, permit => {
     // Desired state can flip OFF during the provider await above. The catalog
diff --git a/src/codex/convergence.ts b/src/codex/convergence.ts
index e33e654481..99d4e36794 100644
--- a/src/codex/convergence.ts
+++ b/src/codex/convergence.ts
@@ -74,9 +74,9 @@ import { MAIN_CODEX_ACCOUNT_ID } from "./main-account";
 import {
   availableAccountGatedNativeModels,
   isCodexModelEntitlementSnapshotCurrent,
-  resolveCodexModelEntitlements,
   type CodexModelEntitlementSnapshot,
 } from "./model-entitlements";
+import { resolveAdmittedCodexModelEntitlements } from "./model-entitlement-admission";
 import { ACCOUNT_GATED_NATIVE_OPENAI_MODELS } from "./catalog/native-models";
 import { providerCodexAccountMode } from "../providers/registry";
 import { OPENAI_CODEX_PROVIDER_ID } from "../providers/openai-tiers";
@@ -412,7 +412,7 @@ export async function gatherCodexCatalogCandidate(
         providerModelOutcomes,
         discoveryPolicySnapshots: discoveryPolicies,
       }),
-      resolveCodexModelEntitlements(snapshot.config),
+      resolveAdmittedCodexModelEntitlements(snapshot.config),
     ]);
     const processLocal = processEvidence(source);
     const sourceEvidence = sealCatalogGatherEvidenceSession(session);
diff --git a/src/codex/model-entitlement-admission.ts b/src/codex/model-entitlement-admission.ts
new file mode 100644
index 0000000000..4e95642e9f
--- /dev/null
+++ b/src/codex/model-entitlement-admission.ts
@@ -0,0 +1,63 @@
+import type { AdmissionLease } from "../lib/admission";
+import type { OcxConfig } from "../types";
+import { MAIN_CODEX_ACCOUNT_ID } from "./main-account";
+import {
+  resolveCodexModelEntitlements,
+  type CodexModelEntitlementResolveOptions,
+  type CodexModelEntitlementSnapshot,
+} from "./model-entitlements";
+import { tryAcquireNativeMainProfileClaim } from "./native-main-admission";
+import { withNativeMainSharedClaim } from "./native-main-claim";
+import { resolveNativeProfileContext } from "./native-profile-store";
+import { NativeProfileError } from "./native-profile-types";
+
+interface ModelEntitlementAdmissionDeps {
+  readonly acquireNativeMain?: () => AdmissionLease | null;
+  readonly resolve?: typeof resolveCodexModelEntitlements;
+  readonly withSharedClaim?: <T>(operation: () => Promise<T>) => Promise<T>;
+}
+
+function excludeNativeMain(
+  options: CodexModelEntitlementResolveOptions,
+): CodexModelEntitlementResolveOptions {
+  return {
+    ...options,
+    excludeAccountIds: new Set([
+      ...(options.excludeAccountIds ?? []),
+      MAIN_CODEX_ACCOUNT_ID,
+    ]),
+  };
+}
+
+/**
+ * Resolve background/data-plane entitlements inside both native-main fences.
+ *
+ * Pool discovery remains available when startup recovery or a profile drain
+ * owns the physical credential. When main is admitted, the process-local lease
+ * and cross-process shared claim cover its complete read/possible refresh.
+ */
+export async function resolveAdmittedCodexModelEntitlements(
+  config: Pick<OcxConfig, "codexAccounts">,
+  options: CodexModelEntitlementResolveOptions = {},
+  deps: ModelEntitlementAdmissionDeps = {},
+): Promise<CodexModelEntitlementSnapshot> {
+  const resolve = deps.resolve ?? resolveCodexModelEntitlements;
+  const lease = (deps.acquireNativeMain ?? tryAcquireNativeMainProfileClaim)();
+  if (!lease) return resolve(config, excludeNativeMain(options));
+
+  try {
+    const operation = () => resolve(config, options);
+    const withSharedClaim = deps.withSharedClaim
+      ?? (<T>(work: () => Promise<T>) => withNativeMainSharedClaim(resolveNativeProfileContext(), work));
+    try {
+      return await withSharedClaim(operation);
+    } catch (error) {
+      // A foreign exclusive holder or an unsupported claim filesystem makes
+      // main unavailable; it must not suppress independent Pool discovery.
+      if (!(error instanceof NativeProfileError)) throw error;
+      return await resolve(config, excludeNativeMain(options));
+    }
+  } finally {
+    lease.release();
+  }
+}
diff --git a/src/server/index.ts b/src/server/index.ts
index 6c7e53f062..08c54fabbd 100644
--- a/src/server/index.ts
+++ b/src/server/index.ts
@@ -66,8 +66,8 @@ import { codexAccountNamespaceEntries, isMainCodexAccountTarget } from "../codex
 import { MAIN_CODEX_ACCOUNT_ID } from "../codex/main-account";
 import {
   availableAccountGatedNativeModels,
-  resolveCodexModelEntitlements,
 } from "../codex/model-entitlements";
+import { resolveAdmittedCodexModelEntitlements } from "../codex/model-entitlement-admission";
 export {
   clearThreadAccountMap,
   formatCodexProviderForLog,
@@ -1160,7 +1160,7 @@ export function startServer(port?: number, deps: StartServerDeps = {}): Server<W
             // Codex sends its own client_version on this request, and upstream filters the
             // entitlement roster by it. Passing it through is what stops an entitled account
             // being told it cannot use models a newer client can (#2886).
-            resolveCodexModelEntitlements(config, { clientVersion: url.searchParams.get("client_version") }),
+            resolveAdmittedCodexModelEntitlements(config, { clientVersion: url.searchParams.get("client_version") }),
           ]);
         } catch (error) {
           if (error instanceof CatalogGatherBusyError) {
diff --git a/tests/codex-model-entitlement-admission.test.ts b/tests/codex-model-entitlement-admission.test.ts
new file mode 100644
index 0000000000..b08e8fdf1f
--- /dev/null
+++ b/tests/codex-model-entitlement-admission.test.ts
@@ -0,0 +1,75 @@
+import { describe, expect, test } from "bun:test";
+
+import { MAIN_CODEX_ACCOUNT_ID } from "../src/codex/main-account";
+import { resolveAdmittedCodexModelEntitlements } from "../src/codex/model-entitlement-admission";
+import type { CodexModelEntitlementResolveOptions } from "../src/codex/model-entitlements";
+import { NativeProfileError } from "../src/codex/native-profile-types";
+
+const emptySnapshot = {
+  modelsByAccount: new Map<string, ReadonlySet<string>>(),
+  confirmedAccountIds: new Set<string>(),
+  credentialIdentities: new Map<string, string>(),
+};
+
+describe("Codex model entitlement admission", () => {
+  test("excludes native main before credential discovery when lifecycle admission is blocked", async () => {
+    let received: CodexModelEntitlementResolveOptions | undefined;
+
+    await resolveAdmittedCodexModelEntitlements({ codexAccounts: [] }, {}, {
+      acquireNativeMain: () => null,
+      resolve: async (_config, options) => {
+        received = options;
+        return emptySnapshot;
+      },
+    });
+
+    expect(received?.excludeAccountIds?.has(MAIN_CODEX_ACCOUNT_ID)).toBe(true);
+  });
+
+  test("holds lifecycle and shared claims through credential discovery", async () => {
+    const events: string[] = [];
+    let released = false;
+
+    await resolveAdmittedCodexModelEntitlements({ codexAccounts: [] }, {}, {
+      acquireNativeMain: () => ({ release: () => {
+        released = true;
+        events.push("lifecycle-release");
+      } }),
+      withSharedClaim: async operation => {
+        events.push("shared-enter");
+        const result = await operation();
+        events.push("shared-release");
+        return result;
+      },
+      resolve: async () => {
+        expect(released).toBe(false);
+        events.push("credential-discovery");
+        return emptySnapshot;
+      },
+    });
+
+    expect(events).toEqual([
+      "shared-enter",
+      "credential-discovery",
+      "shared-release",
+      "lifecycle-release",
+    ]);
+  });
+
+  test("falls back to Pool-only discovery when the shared claim is unavailable", async () => {
+    const exclusions: boolean[] = [];
+
+    await resolveAdmittedCodexModelEntitlements({ codexAccounts: [] }, {}, {
+      acquireNativeMain: () => ({ release: () => undefined }),
+      withSharedClaim: async () => {
+        throw new NativeProfileError("NATIVE_MAIN_CLAIM_BUSY", "busy", 503, true);
+      },
+      resolve: async (_config, options) => {
+        exclusions.push(options.excludeAccountIds?.has(MAIN_CODEX_ACCOUNT_ID) === true);
+        return emptySnapshot;
+      },
+    });
+
+    expect(exclusions).toEqual([true]);
+  });
+});