diff --git a/packages/adapters/codex-local/src/index.ts b/packages/adapters/codex-local/src/index.ts
index 8bd1d699..4c4a2de0 100644
--- a/packages/adapters/codex-local/src/index.ts
+++ b/packages/adapters/codex-local/src/index.ts
@@ -27,6 +27,11 @@ export function isCodexLocalManualModel(model: string | null | undefined): boole
 export function isCodexLocalFastModeSupported(model: string | null | undefined): boolean {
   if (isCodexLocalManualModel(model)) return true;
   const normalizedModel = typeof model === "string" ? model.trim() : "";
+  // Empty means we're omitting --model so the Codex CLI picks its own default.
+  // On subscription auth that's gpt-5.5 (fast-mode capable); manual model IDs
+  // are also treated as supported. Match that policy: pass the fast-mode
+  // overrides through and let the CLI reject them if the chosen model can't use them.
+  if (!normalizedModel) return true;
   return CODEX_LOCAL_FAST_MODE_SUPPORTED_MODELS.includes(
     normalizedModel as (typeof CODEX_LOCAL_FAST_MODE_SUPPORTED_MODELS)[number],
   );
diff --git a/packages/adapters/codex-local/src/server/codex-args.test.ts b/packages/adapters/codex-local/src/server/codex-args.test.ts
index feb22574..5ef2608d 100644
--- a/packages/adapters/codex-local/src/server/codex-args.test.ts
+++ b/packages/adapters/codex-local/src/server/codex-args.test.ts
@@ -70,6 +70,25 @@ describe("buildCodexExecArgs", () => {
     ]);
   });
 
+  it("enables Codex fast mode overrides when model is omitted (CLI default)", () => {
+    const result = buildCodexExecArgs({
+      fastMode: true,
+    });
+
+    expect(result.fastModeRequested).toBe(true);
+    expect(result.fastModeApplied).toBe(true);
+    expect(result.fastModeIgnoredReason).toBeNull();
+    expect(result.args).toEqual([
+      "exec",
+      "--json",
+      "-c",
+      'service_tier="fast"',
+      "-c",
+      "features.fast_mode=true",
+      "-",
+    ]);
+  });
+
   it("ignores fast mode for unsupported models", () => {
     const result = buildCodexExecArgs({
       model: "gpt-5.3-codex",
diff --git a/packages/adapters/codex-local/src/ui/build-config.test.ts b/packages/adapters/codex-local/src/ui/build-config.test.ts
index 734d1687..8126c0fb 100644
--- a/packages/adapters/codex-local/src/ui/build-config.test.ts
+++ b/packages/adapters/codex-local/src/ui/build-config.test.ts
@@ -51,4 +51,10 @@ describe("buildCodexLocalConfig", () => {
       dangerouslyBypassApprovalsAndSandbox: true,
     });
   });
+
+  it("omits model when the operator leaves it blank", () => {
+    const config = buildCodexLocalConfig(makeValues({ model: "" }));
+
+    expect(config).not.toHaveProperty("model");
+  });
 });
diff --git a/packages/adapters/codex-local/src/ui/build-config.ts b/packages/adapters/codex-local/src/ui/build-config.ts
index 78e5e806..ab67feb6 100644
--- a/packages/adapters/codex-local/src/ui/build-config.ts
+++ b/packages/adapters/codex-local/src/ui/build-config.ts
@@ -1,8 +1,5 @@
 import type { CreateConfigValues } from "@paperclipai/adapter-utils";
-import {
-  DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX,
-  DEFAULT_CODEX_LOCAL_MODEL,
-} from "../index.js";
+import { DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX } from "../index.js";
 
 function parseCommaArgs(value: string): string[] {
   return value
@@ -70,7 +67,7 @@ export function buildCodexLocalConfig(v: CreateConfigValues): Record<string, unk
   const ac: Record<string, unknown> = {};
   if (v.cwd) ac.cwd = v.cwd;
   if (v.instructionsFilePath) ac.instructionsFilePath = v.instructionsFilePath;
-  ac.model = v.model || DEFAULT_CODEX_LOCAL_MODEL;
+  if (v.model) ac.model = v.model;
   if (v.thinkingEffort) ac.modelReasoningEffort = v.thinkingEffort;
   ac.timeoutSec = 0;
   ac.graceSec = 15;
diff --git a/server/src/routes/agents.ts b/server/src/routes/agents.ts
index fb706f8e..3182c2bf 100644
--- a/server/src/routes/agents.ts
+++ b/server/src/routes/agents.ts
@@ -85,10 +85,7 @@ import {
   DEFAULT_ACPX_LOCAL_NON_INTERACTIVE_PERMISSIONS,
   DEFAULT_ACPX_LOCAL_PERMISSION_MODE,
 } from "@paperclipai/adapter-acpx-local";
-import {
-  DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX,
-  DEFAULT_CODEX_LOCAL_MODEL,
-} from "@paperclipai/adapter-codex-local";
+import { DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX } from "@paperclipai/adapter-codex-local";
 import { DEFAULT_CURSOR_LOCAL_MODEL } from "@paperclipai/adapter-cursor-local";
 import { DEFAULT_GEMINI_LOCAL_MODEL } from "@paperclipai/adapter-gemini-local";
 import { DEFAULT_OPENCODE_LOCAL_MODEL } from "@paperclipai/adapter-opencode-local";
@@ -1112,9 +1109,6 @@ export function agentRoutes(
       return ensureGatewayDeviceKey(adapterType, next);
     }
     if (adapterType === "codex_local") {
-      if (!asNonEmptyString(next.model)) {
-        next.model = DEFAULT_CODEX_LOCAL_MODEL;
-      }
       const hasBypassFlag =
         typeof next.dangerouslyBypassApprovalsAndSandbox === "boolean" ||
         typeof next.dangerouslyBypassSandbox === "boolean";
diff --git a/ui/src/components/AgentConfigForm.tsx b/ui/src/components/AgentConfigForm.tsx
index 9532ba5d..264e61e9 100644
--- a/ui/src/components/AgentConfigForm.tsx
+++ b/ui/src/components/AgentConfigForm.tsx
@@ -14,10 +14,7 @@ import { environmentsApi } from "../api/environments";
 import { instanceSettingsApi } from "../api/instanceSettings";
 import { secretsApi } from "../api/secrets";
 import { assetsApi } from "../api/assets";
-import {
-  DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX,
-  DEFAULT_CODEX_LOCAL_MODEL,
-} from "@paperclipai/adapter-codex-local";
+import { DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX } from "@paperclipai/adapter-codex-local";
 import { DEFAULT_CURSOR_LOCAL_MODEL } from "@paperclipai/adapter-cursor-local";
 import { DEFAULT_GEMINI_LOCAL_MODEL } from "@paperclipai/adapter-gemini-local";
 import { DEFAULT_OPENCODE_LOCAL_MODEL } from "@paperclipai/adapter-opencode-local";
@@ -852,7 +849,6 @@ export function AgentConfigForm(props: AgentConfigFormProps) {
                     const { adapterType: _at, ...defaults } = defaultCreateValues;
                     const nextValues: CreateConfigValues = { ...defaults, adapterType: t };
                     if (t === "codex_local") {
-                      nextValues.model = DEFAULT_CODEX_LOCAL_MODEL;
                       nextValues.dangerouslyBypassSandbox =
                         DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX;
                     } else if (t === "gemini_local") {
@@ -872,10 +868,8 @@ export function AgentConfigForm(props: AgentConfigFormProps) {
                       modelProfiles: { cheap: { cleared: true } },
                       adapterConfig: {
                         model:
-                          t === "codex_local"
-                            ? DEFAULT_CODEX_LOCAL_MODEL
-                            : t === "gemini_local"
-                              ? DEFAULT_GEMINI_LOCAL_MODEL
+                          t === "gemini_local"
+                            ? DEFAULT_GEMINI_LOCAL_MODEL
                             : t === "opencode_local"
                               ? DEFAULT_OPENCODE_LOCAL_MODEL
                             : t === "cursor"
diff --git a/ui/src/components/OnboardingWizard.tsx b/ui/src/components/OnboardingWizard.tsx
index 0f9c2378..f30168cd 100644
--- a/ui/src/components/OnboardingWizard.tsx
+++ b/ui/src/components/OnboardingWizard.tsx
@@ -37,10 +37,7 @@ import {
   selectDefaultCompanyGoalId
 } from "../lib/onboarding-launch";
 import { buildNewAgentRuntimeConfig } from "../lib/new-agent-runtime-config";
-import {
-  DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX,
-  DEFAULT_CODEX_LOCAL_MODEL
-} from "@paperclipai/adapter-codex-local";
+import { DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX } from "@paperclipai/adapter-codex-local";
 import { DEFAULT_CURSOR_LOCAL_MODEL } from "@paperclipai/adapter-cursor-local";
 import { DEFAULT_GEMINI_LOCAL_MODEL } from "@paperclipai/adapter-gemini-local";
 import { DEFAULT_OPENCODE_LOCAL_MODEL, isValidOpenCodeModelId } from "@paperclipai/adapter-opencode-local";
@@ -322,10 +319,8 @@ export function OnboardingWizard() {
       ...defaultCreateValues,
       adapterType,
       model:
-        adapterType === "codex_local"
-          ? model || DEFAULT_CODEX_LOCAL_MODEL
-          : adapterType === "gemini_local"
-            ? model || DEFAULT_GEMINI_LOCAL_MODEL
+        adapterType === "gemini_local"
+          ? model || DEFAULT_GEMINI_LOCAL_MODEL
           : adapterType === "cursor"
             ? model || DEFAULT_CURSOR_LOCAL_MODEL
             : adapterType === "opencode_local"
@@ -754,9 +749,6 @@ export function OnboardingWizard() {
                             const nextType = opt.type;
                             setAdapterType(nextType);
                             if (nextType === "codex_local") {
-                              if (!model) {
-                                setModel(DEFAULT_CODEX_LOCAL_MODEL);
-                              }
                               return;
                             }
                             if (nextType === "opencode_local") {
diff --git a/ui/src/pages/NewAgent.tsx b/ui/src/pages/NewAgent.tsx
index efb9411a..a786defc 100644
--- a/ui/src/pages/NewAgent.tsx
+++ b/ui/src/pages/NewAgent.tsx
@@ -32,10 +32,7 @@ import { ReportsToPicker } from "../components/ReportsToPicker";
 import { buildNewAgentHirePayload } from "../lib/new-agent-hire-payload";
 import { TrustPresetSection } from "../components/TrustPresetSection";
 import { buildPermissionsForTrustPreset, getTrustPreset } from "../lib/trust-policy-ui";
-import {
-  DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX,
-  DEFAULT_CODEX_LOCAL_MODEL,
-} from "@paperclipai/adapter-codex-local";
+import { DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX } from "@paperclipai/adapter-codex-local";
 import { DEFAULT_CURSOR_LOCAL_MODEL } from "@paperclipai/adapter-cursor-local";
 import { DEFAULT_GEMINI_LOCAL_MODEL } from "@paperclipai/adapter-gemini-local";
 import { DEFAULT_OPENCODE_LOCAL_MODEL, isValidOpenCodeModelId } from "@paperclipai/adapter-opencode-local";
@@ -46,7 +43,6 @@ function createValuesForAdapterType(
   const { adapterType: _discard, ...defaults } = defaultCreateValues;
   const nextValues: CreateConfigValues = { ...defaults, adapterType };
   if (adapterType === "codex_local") {
-    nextValues.model = DEFAULT_CODEX_LOCAL_MODEL;
     nextValues.dangerouslyBypassSandbox =
       DEFAULT_CODEX_LOCAL_BYPASS_APPROVALS_AND_SANDBOX;
   } else if (adapterType === "gemini_local") {