diff --git a/apps/mobile/src/features/threads/SubagentRow.tsx b/apps/mobile/src/features/threads/SubagentRow.tsx
index ffca391f260ab..7c71ac2680de1 100644
--- a/apps/mobile/src/features/threads/SubagentRow.tsx
+++ b/apps/mobile/src/features/threads/SubagentRow.tsx
@@ -5,6 +5,7 @@ import {
   shouldShowInstanceBadge,
 } from "@t3tools/client-runtime/state/provider-instance-display";
 import { resolveSubagentMetadata } from "@t3tools/client-runtime/state/subagent-display";
+import { formatSubagentEffort } from "@t3tools/client-runtime/state/thread-execution";
 import type { EnvironmentId, OrchestrationV2Subagent } from "@t3tools/contracts";
 import type { ReactNode } from "react";
 import { View } from "react-native";
@@ -23,6 +24,7 @@ type SubagentRowSubagent = Pick<
   | "threadId"
   | "childThreadId"
   | "model"
+  | "modelSelection"
   | "driver"
   | "providerInstanceId"
   | "title"
@@ -132,14 +134,17 @@ function SubagentMetadata(props: {
     parent ? scopeProjectRef(environmentId, parent.projectId) : null,
   );
   const childProject = useProject(child ? scopeProjectRef(environmentId, child.projectId) : null);
-  const { modelLabel, workspace } = resolveSubagentMetadata({
+  const selection = subagent.modelSelection;
+  const { modelLabel, modelSlug, workspace } = resolveSubagentMetadata({
     model: subagent.model,
+    modelSelection: selection,
     provider,
     parentThread: parent,
     childThread: child,
     parentProject,
     childProject,
   });
+  const effort = formatSubagentEffort({ modelSlug, modelSelection: selection, provider });
   return (
     <View className="min-w-0 flex-row items-center gap-1.5">
       {showBadge ? (
@@ -161,6 +166,7 @@ function SubagentMetadata(props: {
       <Text className="min-w-0 shrink text-xs text-foreground-muted" numberOfLines={1}>
         {provider ? `${resolveProviderInstanceDisplayName(provider)} · ` : ""}
         {modelLabel}
+        {effort ? ` · ${effort}` : ""}
       </Text>
       {workspace.map(({ label, value }) => (
         // Preserve the label against flattening without making it a separate accessibility stop.
diff --git a/apps/mobile/src/features/threads/thread-subagent-group.tsx b/apps/mobile/src/features/threads/thread-subagent-group.tsx
index 4a42a83c9a371..f3d3f3b5252b6 100644
--- a/apps/mobile/src/features/threads/thread-subagent-group.tsx
+++ b/apps/mobile/src/features/threads/thread-subagent-group.tsx
@@ -128,6 +128,7 @@ export function ThreadSubagentGroup(props: {
       result: live?.result ?? item.result,
       progress: live?.progress ?? item.progress,
       model: live?.model ?? null,
+      modelSelection: live?.modelSelection,
     };
   });
   const grouped = agents.length > 1;
diff --git a/apps/mobile/src/features/threads/thread-workflow-opening.tsx b/apps/mobile/src/features/threads/thread-workflow-opening.tsx
index b16a82b7190d9..9919e2e9854b7 100644
--- a/apps/mobile/src/features/threads/thread-workflow-opening.tsx
+++ b/apps/mobile/src/features/threads/thread-workflow-opening.tsx
@@ -2,6 +2,7 @@ import { useAtomValue } from "@effect/atom-react";
 import { scopeThreadRef } from "@t3tools/client-runtime/environment";
 import {
   resolveWorkflowOpening,
+  workflowMemberModelSelection,
   workflowOpeningHeadline,
   workflowOpeningParentThreadId,
   type RuntimeSubagent,
@@ -63,6 +64,7 @@ function memberRowSubagent(
     threadId: coordinatorThreadId,
     childThreadId: member.childThreadId as ThreadId | null,
     model: member.model,
+    modelSelection: workflowMemberModelSelection(member, opening.providerInstanceId!),
     driver: opening.driver!,
     providerInstanceId: opening.providerInstanceId!,
     title: member.title,
diff --git a/apps/server/src/claudeModelOptions.test.ts b/apps/server/src/claudeModelOptions.test.ts
index 4a34d98a796bd..b69b20db7ec4d 100644
--- a/apps/server/src/claudeModelOptions.test.ts
+++ b/apps/server/src/claudeModelOptions.test.ts
@@ -3,6 +3,10 @@ import { describe, expect, it } from "@effect/vitest";
 import { ProviderInstanceId, type ModelSelection } from "@t3tools/contracts";
 
 import { compileClaudeModelSelection } from "./claudeModelOptions.ts";
+import {
+  BUNDLED_CLAUDE_MODEL_CATALOG,
+  scopeClaudeModelCatalog,
+} from "./provider/ClaudeModelCatalog.ts";
 
 const selection = (
   model: string,
@@ -30,6 +34,69 @@ describe("compileClaudeModelSelection", () => {
     });
   });
 
+  it("runs Ultracode at the chosen effort and reads the old Ultracode effort as xhigh", () => {
+    expect(
+      compileClaudeModelSelection(
+        selection("claude-opus-5-5", [
+          { id: "effort", value: "high" },
+          { id: "ultracode", value: true },
+        ]),
+      ),
+    ).toMatchObject({ effort: "high", settings: { ultracode: true } });
+    expect(
+      compileClaudeModelSelection(
+        selection("claude-opus-5-5", [{ id: "effort", value: "ultracode" }]),
+      ),
+    ).toMatchObject({ effort: "xhigh", settings: { ultracode: true } });
+    const legacyTurnedOff = compileClaudeModelSelection(
+      selection("claude-opus-5-5", [
+        { id: "effort", value: "ultracode" },
+        { id: "ultracode", value: false },
+      ]),
+    );
+    expect(legacyTurnedOff.effort).toBe("xhigh");
+    expect(legacyTurnedOff.settings.ultracode).toBe(false);
+    expect(
+      compileClaudeModelSelection(selection("claude-opus-5-5", [{ id: "effort", value: "high" }]))
+        .settings,
+    ).not.toHaveProperty("ultracode");
+  });
+
+  it("keeps old Ultracode defaults and selections at Extra High on custom models", () => {
+    const customModel = (slug: string, choices: ReadonlyArray<string>) => ({
+      slug,
+      name: slug,
+      capabilities: {
+        optionDescriptors: [
+          {
+            id: "effort",
+            label: "Reasoning",
+            type: "select" as const,
+            currentValue: "ultracode",
+            options: choices.map((id) => ({ id, label: id, isDefault: id === "ultracode" })),
+          },
+        ],
+      },
+    });
+    const catalog = scopeClaudeModelCatalog(BUNDLED_CLAUDE_MODEL_CATALOG, [
+      customModel("claude-custom-tuned", ["high", "xhigh", "ultracode"]),
+      customModel("claude-custom-no-xhigh", ["high", "ultracode"]),
+    ]);
+
+    for (const model of ["claude-custom-tuned", "claude-custom-no-xhigh"]) {
+      expect(compileClaudeModelSelection(selection(model, []), catalog)).toMatchObject({
+        effort: "xhigh",
+        settings: { ultracode: true },
+      });
+      expect(
+        compileClaudeModelSelection(
+          selection(model, [{ id: "effort", value: "ultracode" }]),
+          catalog,
+        ),
+      ).toMatchObject({ effort: "xhigh", settings: { ultracode: true } });
+    }
+  });
+
   it("uses the model default SDK effort alongside prompt-injected effort", () => {
     expect(
       compileClaudeModelSelection(
diff --git a/apps/server/src/claudeModelOptions.ts b/apps/server/src/claudeModelOptions.ts
index 06841da9bdb28..7d815f5f9af55 100644
--- a/apps/server/src/claudeModelOptions.ts
+++ b/apps/server/src/claudeModelOptions.ts
@@ -9,7 +9,6 @@ import {
 import {
   BUNDLED_CLAUDE_MODEL_CATALOG,
   getClaudeCatalogModelCapabilities,
-  isClaudeCatalogUltracodeEffort,
   normalizeClaudeCatalogEffort,
   resolveClaudeCatalogApiModelId,
   resolveClaudeCatalogEffort,
@@ -29,7 +28,10 @@ export function compileClaudeModelSelection(
   catalog: ClaudeModelCatalog = BUNDLED_CLAUDE_MODEL_CATALOG,
 ): CompiledClaudeModelSelection {
   const capabilities = getClaudeCatalogModelCapabilities(catalog, selection.model);
-  const descriptors = getProviderOptionDescriptors({ caps: capabilities });
+  const descriptors = getProviderOptionDescriptors({
+    caps: capabilities,
+    selections: selection.options,
+  });
   const supportsBoolean = (id: string) =>
     descriptors.some((descriptor) => descriptor.type === "boolean" && descriptor.id === id);
   const rawEffort = getModelSelectionStringOptionValue(selection, "effort");
@@ -41,10 +43,11 @@ export function compileClaudeModelSelection(
   const thinking = supportsBoolean("thinking")
     ? getModelSelectionBooleanOptionValue(selection, "thinking")
     : undefined;
+  const ultracode = descriptors.find((descriptor) => descriptor.id === "ultracode")?.currentValue;
   const settings = {
     ...(typeof thinking === "boolean" ? { alwaysThinkingEnabled: thinking } : {}),
     ...(typeof fastMode === "boolean" ? { fastMode } : {}),
-    ...(isClaudeCatalogUltracodeEffort(resolvedEffort) ? { ultracode: true } : {}),
+    ...(typeof ultracode === "boolean" ? { ultracode } : {}),
   };
   const apiModelId = resolveClaudeCatalogApiModelId(catalog, selection);
   const promptEffort = resolvePromptInjectedEffort(capabilities, rawEffort) ?? undefined;
diff --git a/apps/server/src/mcp/OrchestratorMcpService.test.ts b/apps/server/src/mcp/OrchestratorMcpService.test.ts
index 3bd9439d308b4..d66ed5385feee 100644
--- a/apps/server/src/mcp/OrchestratorMcpService.test.ts
+++ b/apps/server/src/mcp/OrchestratorMcpService.test.ts
@@ -3029,6 +3029,18 @@ describe("OrchestratorMcpService provider resolution", () => {
             target: { providerInstanceId: peerId, options: { reasoningEffort: "max" } },
             expected: { instanceId: peerId, model: inherited.model, options: override },
           },
+          {
+            name: "old Ultracode effort level",
+            target: { model: "ultracode-model", options: { effort: "ultracode" } },
+            expected: {
+              instanceId: codexInstanceId,
+              model: "ultracode-model",
+              options: [
+                { id: "effort", value: "xhigh" },
+                { id: "ultracode", value: true },
+              ],
+            },
+          },
         ] as const;
         for (const testCase of cases) {
           const commands: Array<unknown> = [];
@@ -3071,12 +3083,33 @@ describe("OrchestratorMcpService provider resolution", () => {
                   driver,
                   model: inherited.model,
                 }),
-                models: [inherited.model, "other-model"].map((model) => ({
-                  slug: model,
-                  name: model,
-                  isCustom: false,
-                  capabilities: null,
-                })),
+                models: [
+                  ...[inherited.model, "other-model"].map((model) => ({
+                    slug: model,
+                    name: model,
+                    isCustom: false,
+                    capabilities: null,
+                  })),
+                  {
+                    slug: "ultracode-model",
+                    name: "ultracode-model",
+                    isCustom: false,
+                    capabilities: {
+                      optionDescriptors: [
+                        {
+                          id: "effort",
+                          label: "Reasoning",
+                          type: "select",
+                          options: [
+                            { id: "high", label: "High" },
+                            { id: "xhigh", label: "Extra High" },
+                          ],
+                        },
+                        { id: "ultracode", label: "Ultracode", type: "boolean" },
+                      ],
+                    },
+                  },
+                ],
               },
               providerSnapshot({ instanceId: peerId, driver, model: inherited.model }),
             ]),
diff --git a/apps/server/src/mcp/OrchestratorMcpService.ts b/apps/server/src/mcp/OrchestratorMcpService.ts
index b937453f39b22..7719794b25333 100644
--- a/apps/server/src/mcp/OrchestratorMcpService.ts
+++ b/apps/server/src/mcp/OrchestratorMcpService.ts
@@ -63,7 +63,7 @@ import {
   ThreadId,
   isOrchestrationV2WorkActive,
 } from "@t3tools/contracts";
-import { getProviderOptionCurrentValue } from "@t3tools/shared/model";
+import { getProviderOptionCurrentValue, withLegacyUltracodeEffort } from "@t3tools/shared/model";
 import { runRanAfter } from "@t3tools/shared/orchestrationV2ThreadError";
 import { formatThreadLink } from "@t3tools/shared/threadLinks";
 import {
@@ -1432,7 +1432,7 @@ const make = Effect.gen(function* () {
 
     const descriptors = provider.models.find((candidate) => candidate.slug === model)?.capabilities
       ?.optionDescriptors;
-    const requestedOptions = input.target?.options;
+    const requestedOptions = withLegacyUltracodeEffort(descriptors, input.target?.options);
     if (requestedOptions !== undefined) {
       const invalid = invalidOptionSelections(requestedOptions, descriptors);
       if (invalid.length > 0) {
@@ -1446,7 +1446,10 @@ const make = Effect.gen(function* () {
     const inheritsOptions =
       instanceId === inheritedSelection.instanceId && model === inheritedSelection.model;
     let options = inheritsOptions
-      ? knownOptions(inheritedSelection.options, descriptors)
+      ? knownOptions(
+          withLegacyUltracodeEffort(descriptors, inheritedSelection.options),
+          descriptors,
+        )
       : undefined;
     if (requestedOptions !== undefined) {
       const selections = new Map(
diff --git a/apps/server/src/orchestration-v2/Adapters/ClaudeAdapterV2.test.ts b/apps/server/src/orchestration-v2/Adapters/ClaudeAdapterV2.test.ts
index 45d21b5944e24..1505bc5d27d94 100644
--- a/apps/server/src/orchestration-v2/Adapters/ClaudeAdapterV2.test.ts
+++ b/apps/server/src/orchestration-v2/Adapters/ClaudeAdapterV2.test.ts
@@ -148,6 +148,26 @@ const CUSTOM_MODEL_CLAUDE_SETTINGS = Schema.decodeSync(ClaudeSettings)({
     },
   ],
 });
+const ULTRACODE_CUSTOM_MODEL_CLAUDE_SETTINGS = Schema.decodeSync(ClaudeSettings)({
+  customModels: [
+    {
+      slug: "claude-custom-tuned",
+      capabilities: {
+        optionDescriptors: [
+          {
+            id: "effort",
+            label: "Reasoning",
+            type: "select",
+            options: [
+              { id: "high", label: "High", isDefault: true },
+              { id: "ultracode", label: "Ultracode" },
+            ],
+          },
+        ],
+      },
+    },
+  ],
+});
 const CLAUDE_TEST_MODEL_SELECTION = {
   instanceId: ProviderInstanceId.make(ClaudeAdapterV2.CLAUDE_PROVIDER),
   model: "claude-sonnet-4-6",
@@ -5191,7 +5211,8 @@ describe("ClaudeAdapterV2 background wake turns", () => {
             turn(3, {
               ...normal,
               options: [
-                { id: "effort", value: "ultracode" },
+                { id: "effort", value: "high" },
+                { id: "ultracode", value: true },
                 { id: "fastMode", value: true },
               ],
             }),
@@ -5200,7 +5221,7 @@ describe("ClaudeAdapterV2 background wake turns", () => {
           yield* harness.runtime.startTurn(turn(4, { ...normal, model: "claude-sonnet-4-6" }));
           yield* settle;
           assert.deepEqual(harness.liveSelectionChanges, [
-            { effortLevel: "xhigh", fastMode: true, ultracode: true },
+            { effortLevel: "high", fastMode: true, ultracode: true },
             { model: "claude-sonnet-4-6" },
             { effortLevel: "high", fastMode: null, ultracode: null },
           ]);
@@ -14116,6 +14137,46 @@ describe("ClaudeAdapterV2 background wake turns", () => {
       ),
   );
 
+  it.effect("sends Ultracode with any effort on a custom model", () =>
+    Effect.scoped(
+      Effect.gen(function* () {
+        const harness = yield* makeWakeHarnessWithOptions({
+          settings: ULTRACODE_CUSTOM_MODEL_CLAUDE_SETTINGS,
+        });
+        yield* harness.runtime.startTurn(
+          makeClaudeTestTurnInput({
+            threadId: harness.threadId,
+            providerThread: harness.providerThread,
+            now: yield* DateTime.now,
+            attemptId: RunAttemptId.make("attempt-custom-ultracode"),
+            text: "Plan the work.",
+            attachments: [],
+            modelSelection: {
+              instanceId: ClaudeAdapterV2.CLAUDE_DEFAULT_INSTANCE_ID,
+              model: "claude-custom-tuned",
+              options: [
+                { id: "effort", value: "high" },
+                { id: "ultracode", value: true },
+              ],
+            },
+          }),
+        );
+        const options = harness.getOpenedOptions()!;
+        assert.equal(options.effort, "high");
+        assert.equal((options.settings as { ultracode?: boolean }).ultracode, true);
+      }).pipe(
+        Effect.provide(
+          Layer.mergeAll(
+            IdAllocator.layer,
+            McpProviderSessions.layer,
+            NodeServices.layer,
+            NodeCrypto.layer,
+          ),
+        ),
+      ),
+    ),
+  );
+
   it.effect("resolves a subagent's model and effort against the instance's custom models", () =>
     Effect.scoped(
       Effect.gen(function* () {
diff --git a/apps/server/src/orchestration-v2/Adapters/ClaudeAdapterV2.ts b/apps/server/src/orchestration-v2/Adapters/ClaudeAdapterV2.ts
index 674f55c524d75..52ed0e9d10016 100644
--- a/apps/server/src/orchestration-v2/Adapters/ClaudeAdapterV2.ts
+++ b/apps/server/src/orchestration-v2/Adapters/ClaudeAdapterV2.ts
@@ -1525,6 +1525,7 @@ const subagentDeviceInstructions: HookCallback = () =>
 
 export function makeClaudeQueryOptions(input: {
   readonly modelSelection: ModelSelection;
+  readonly modelCatalog?: ClaudeModelCatalog;
   readonly nativeThreadId: string;
   readonly title?: string;
   readonly resume: boolean;
@@ -1550,7 +1551,7 @@ export function makeClaudeQueryOptions(input: {
   // Flag settings, because a user's settings.json env beats the process env in Claude Code.
   readonly toolSearchOverride?: "true";
 }): ClaudeAgentSdkQueryOptions {
-  const compiledSelection = compileClaudeModelSelection(input.modelSelection);
+  const compiledSelection = compileClaudeModelSelection(input.modelSelection, input.modelCatalog);
   const {
     // claudeLaunchArgDirectories reads every --add-dir into additionalDirectories.
     "add-dir": _launchArgAddDir,
@@ -4616,7 +4617,7 @@ export const makeClaudeAdapterV2 = Effect.fn("makeClaudeAdapterV2")(function* (
   const spawner = yield* ChildProcessSpawner.ChildProcessSpawner;
   const serverSettings = yield* Effect.serviceOption(ServerSettings.ServerSettingsService);
   const { attachmentsDir, fileSystem, path, random, idAllocator, queryRunner } = adapterOptions;
-  const subagentModelCatalog = scopeClaudeModelCatalog(
+  const modelCatalog = scopeClaudeModelCatalog(
     BUNDLED_CLAUDE_MODEL_CATALOG,
     adapterOptions.settings.customModels,
   );
@@ -6527,7 +6528,8 @@ export const makeClaudeAdapterV2 = Effect.fn("makeClaudeAdapterV2")(function* (
             existingSubagent === undefined
               ? (input.effort ??
                 input.owner?.effort ??
-                compileClaudeModelSelection(input.context.input.modelSelection).effort)
+                compileClaudeModelSelection(input.context.input.modelSelection, modelCatalog)
+                  .effort)
               : existingSubagent.effort;
           const model = input.model ?? priorTask?.model ?? null;
           const task = {
@@ -6565,7 +6567,7 @@ export const makeClaudeAdapterV2 = Effect.fn("makeClaudeAdapterV2")(function* (
             ...(existingSubagent === undefined || existingSubagent.task.modelSelection !== undefined
               ? {
                   modelSelection: claudeSubagentModelSelection(
-                    subagentModelCatalog,
+                    modelCatalog,
                     input.context.input.modelSelection.instanceId,
                     model || input.context.input.modelSelection.model,
                     effort,
@@ -8995,7 +8997,7 @@ export const makeClaudeAdapterV2 = Effect.fn("makeClaudeAdapterV2")(function* (
             const model =
               snapshotModel.length === 0 || snapshotModel === "<synthetic>"
                 ? undefined
-                : canonicalClaudeSubagentModel(subagentModelCatalog, snapshotModel);
+                : canonicalClaudeSubagentModel(modelCatalog, snapshotModel);
             if (parentToolUseId !== null && model !== undefined) {
               const subagent = yield* resolveSubagentByToolUseId(context, parentToolUseId);
               if (subagent === undefined) {
@@ -9301,7 +9303,7 @@ export const makeClaudeAdapterV2 = Effect.fn("makeClaudeAdapterV2")(function* (
             const nativeToolInput = claudeNativeToolInputFromUnknown(toolUse.input);
             if (toolUse.name === "Agent") {
               rememberClaudeSubagentLaunch(
-                subagentModelCatalog,
+                modelCatalog,
                 context,
                 pendingSubagentLaunchesByToolUseId,
                 toolUse.id,
@@ -9889,7 +9891,7 @@ export const makeClaudeAdapterV2 = Effect.fn("makeClaudeAdapterV2")(function* (
           const startToolCall = toolName !== "Agent" && options?.startToolCall !== false;
           if (toolName === "Agent") {
             rememberClaudeSubagentLaunch(
-              subagentModelCatalog,
+              modelCatalog,
               context,
               pendingSubagentLaunchesByToolUseId,
               nativeRequestId,
@@ -10392,7 +10394,10 @@ export const makeClaudeAdapterV2 = Effect.fn("makeClaudeAdapterV2")(function* (
               : { allowedTools: queryPolicy.allowedTools }),
           });
           const queryPolicyKey = claudeEffectiveQueryPolicyKey(queryPolicy, mcpOverrides);
-          const compiledSelection = compileClaudeModelSelection(turnInput.modelSelection);
+          const compiledSelection = compileClaudeModelSelection(
+            turnInput.modelSelection,
+            modelCatalog,
+          );
           const resumeSessionAt = yield* getNativeConversationHeadId(turnInput.providerThread);
           const existing = yield* Ref.get(queryContext);
           // Continuations drain existing output without prompting; retain the live process regardless of selection.
@@ -10507,6 +10512,7 @@ export const makeClaudeAdapterV2 = Effect.fn("makeClaudeAdapterV2")(function* (
           );
           const queryOptions = makeClaudeQueryOptions({
             modelSelection: turnInput.modelSelection,
+            modelCatalog,
             nativeThreadId,
             title: turnInput.appThread.title,
             resume: shouldResume,
@@ -10745,7 +10751,8 @@ export const makeClaudeAdapterV2 = Effect.fn("makeClaudeAdapterV2")(function* (
                 : yield* makeClaudeUserMessageWithAttachments({
                     text: applyClaudePromptEffortPrefix(
                       turnInput.message.text,
-                      compileClaudeModelSelection(turnInput.modelSelection).promptEffort,
+                      compileClaudeModelSelection(turnInput.modelSelection, modelCatalog)
+                        .promptEffort,
                     ),
                     attachments: turnInput.message.attachments,
                     attachmentsDir,
@@ -11193,7 +11200,8 @@ export const makeClaudeAdapterV2 = Effect.fn("makeClaudeAdapterV2")(function* (
             const userMessage = yield* makeClaudeUserMessageWithAttachments({
               text: applyClaudePromptEffortPrefix(
                 turnInput.message.text,
-                compileClaudeModelSelection(currentTurn.input.modelSelection).promptEffort,
+                compileClaudeModelSelection(currentTurn.input.modelSelection, modelCatalog)
+                  .promptEffort,
               ),
               attachments: turnInput.message.attachments,
               priority: "now",
diff --git a/apps/server/src/provider/ClaudeModelCatalog.test.ts b/apps/server/src/provider/ClaudeModelCatalog.test.ts
index 2092429f6d556..76436f729fada 100644
--- a/apps/server/src/provider/ClaudeModelCatalog.test.ts
+++ b/apps/server/src/provider/ClaudeModelCatalog.test.ts
@@ -4,6 +4,7 @@ import { ProviderDriverKind, ProviderInstanceId } from "@t3tools/contracts";
 import { resolveProviderCatalog, type ModelManifestData } from "./ModelManifest.ts";
 import {
   formatClaudeVersionUpgradeMessage,
+  getClaudeCatalogModelCapabilities,
   normalizeClaudeCatalogEffort,
   resolveClaudeCatalogApiModelId,
   resolveClaudeCatalogContextWindowTokens,
@@ -185,6 +186,7 @@ describe("Claude model catalog", () => {
               options: [
                 { id: "gentle", label: "Gentle", isDefault: true },
                 { id: "brutal", label: "Brutal" },
+                { id: "ultracode", label: "Ultracode" },
               ],
             },
           ],
@@ -205,6 +207,12 @@ describe("Claude model catalog", () => {
       resolveClaudeCatalogEffort(catalog, "claude-custom-tuned", "bogus"),
       "gentle",
     );
+    assert.deepStrictEqual(
+      getClaudeCatalogModelCapabilities(catalog, "claude-custom-tuned").optionDescriptors?.map(
+        ({ id, type }) => `${id}:${type}`,
+      ),
+      ["effort:select", "ultracode:boolean"],
+    );
     assert.strictEqual(
       normalizeClaudeCatalogEffort(catalog, "brutal", "claude-custom-tuned"),
       "brutal",
diff --git a/apps/server/src/provider/ClaudeModelCatalog.ts b/apps/server/src/provider/ClaudeModelCatalog.ts
index f67628efb83a3..9d783c0dde8e1 100644
--- a/apps/server/src/provider/ClaudeModelCatalog.ts
+++ b/apps/server/src/provider/ClaudeModelCatalog.ts
@@ -47,8 +47,9 @@ function tryResolveClaudeModelCatalog(
     const profile = decodeClaudeProfileAdapter(entry.profileAdapter ?? {});
     const adapter = decodeClaudeModelAdapter(entry.adapter ?? {});
     if (Option.isNone(profile) || Option.isNone(adapter)) return null;
+    const model = ModelCatalog.catalogServerModel(resolved, entry);
     models.push({
-      model: ModelCatalog.catalogServerModel(resolved, entry),
+      model: { ...model, capabilities: withUltracodeToggle(model.capabilities) },
       runtime: profile.value.claudeCode ?? {},
       compatibility: adapter.value.claudeCode ?? {},
     });
@@ -59,6 +60,51 @@ function tryResolveClaudeModelCatalog(
   };
 }
 
+// The manifest keeps Ultracode as an effort level because released servers read it from main.
+export function withUltracodeToggle(
+  capabilities: ModelCapabilities | null,
+): ModelCapabilities | null {
+  const descriptors = capabilities?.optionDescriptors ?? [];
+  const effortIndex = descriptors.findIndex(
+    (descriptor) =>
+      descriptor.id === "effort" &&
+      descriptor.type === "select" &&
+      descriptor.options.some((option) => option.id === "ultracode"),
+  );
+  const effort = descriptors[effortIndex];
+  if (effort?.type !== "select") return capabilities;
+  const ultracodeByDefault =
+    (effort.currentValue ?? effort.options.find((option) => option.isDefault)?.id) === "ultracode";
+  const hasXhigh = effort.options.some((option) => option.id === "xhigh");
+  // Ultracode ran at xhigh, so a model that offered it keeps xhigh, and its default moves there.
+  const options = effort.options.flatMap(({ isDefault, ...option }) => {
+    if (option.id === "ultracode") {
+      return hasXhigh
+        ? []
+        : [{ id: "xhigh", label: "Extra High", ...(isDefault ? { isDefault } : {}) }];
+    }
+    if (ultracodeByDefault && option.id === "xhigh") return [{ ...option, isDefault: true }];
+    return [isDefault && !ultracodeByDefault ? { ...option, isDefault } : option];
+  });
+  return {
+    optionDescriptors: descriptors.toSpliced(
+      effortIndex,
+      1,
+      {
+        ...effort,
+        ...(effort.currentValue === "ultracode" ? { currentValue: "xhigh" } : {}),
+        options,
+      },
+      {
+        id: "ultracode",
+        label: "Ultracode",
+        type: "boolean",
+        ...(ultracodeByDefault ? { currentValue: true } : {}),
+      },
+    ),
+  };
+}
+
 /** Resolve the fallback on each read so its new-model badges can expire. */
 export function resolveClaudeModelCatalog(
   catalog: ModelCatalog.ProviderCatalog | undefined,
@@ -104,7 +150,7 @@ export function scopeClaudeModelCatalog(
         slug: entry.slug,
         name: entry.name,
         isCustom: true,
-        capabilities: entry.capabilities,
+        capabilities: withUltracodeToggle(entry.capabilities),
       },
       runtime: {},
       compatibility: {},
@@ -235,10 +281,6 @@ export function normalizeClaudeCatalogEffort(
   return effortMap[effort] ?? undefined;
 }
 
-export function isClaudeCatalogUltracodeEffort(effort: string | null | undefined): boolean {
-  return effort === "ultracode";
-}
-
 function resolveClaudeCatalogContextWindow(
   catalog: ClaudeModelCatalog,
   modelSelection: ModelSelection | undefined,
diff --git a/apps/server/src/provider/ClaudeProvider.ts b/apps/server/src/provider/ClaudeProvider.ts
index a596f6131035c..0ec560d0a1ab0 100644
--- a/apps/server/src/provider/ClaudeProvider.ts
+++ b/apps/server/src/provider/ClaudeProvider.ts
@@ -2,6 +2,7 @@ import {
   type ClaudeSettings,
   type ModelCapabilities,
   type ServerProvider,
+  type ServerProviderModel,
   type ServerProviderSlashCommand,
   type ServerProviderResetCredits,
 } from "@t3tools/contracts";
@@ -51,12 +52,26 @@ import {
   formatClaudeVersionUpgradeMessage,
   resolveClaudeModelsForVersion,
   resolveClaudeUpdateRequiredModels,
+  withUltracodeToggle,
 } from "./ClaudeModelCatalog.ts";
 
 const DEFAULT_CLAUDE_MODEL_CAPABILITIES: ModelCapabilities = createModelCapabilities({
   optionDescriptors: [],
 });
 
+function claudeProviderModels(
+  builtInModels: ReadonlyArray<ServerProviderModel>,
+  customModels: ClaudeSettings["customModels"],
+): ReadonlyArray<ServerProviderModel> {
+  return providerModelsFromSettings(
+    builtInModels,
+    customModels,
+    DEFAULT_CLAUDE_MODEL_CAPABILITIES,
+  ).map((model) =>
+    model.isCustom ? { ...model, capabilities: withUltracodeToggle(model.capabilities) } : model,
+  );
+}
+
 const CLAUDE_PRESENTATION = {
   displayName: "Claude",
   showInteractionModeToggle: true,
@@ -466,10 +481,9 @@ export const checkClaudeProviderStatus = Effect.fn("checkClaudeProviderStatus")(
 > {
   const resolvedEnvironment = environment ?? process.env;
   const checkedAt = DateTime.formatIso(yield* DateTime.now);
-  const allModels = providerModelsFromSettings(
+  const allModels = claudeProviderModels(
     modelCatalog.models.map((entry) => entry.model),
     claudeSettings.customModels,
-    DEFAULT_CLAUDE_MODEL_CAPABILITIES,
   );
 
   if (!claudeSettings.enabled) {
@@ -557,10 +571,9 @@ export const checkClaudeProviderStatus = Effect.fn("checkClaudeProviderStatus")(
     });
   }
 
-  const models = providerModelsFromSettings(
+  const models = claudeProviderModels(
     resolveClaudeModelsForVersion(modelCatalog, parsedVersion),
     claudeSettings.customModels,
-    DEFAULT_CLAUDE_MODEL_CAPABILITIES,
   );
   const updateRequiredModels = resolveClaudeUpdateRequiredModels(modelCatalog, parsedVersion);
   const versionUpgradeMessage = formatClaudeVersionUpgradeMessage(modelCatalog, parsedVersion);
@@ -687,10 +700,9 @@ export const makePendingClaudeProvider = Effect.fn("ClaudeProvider.makePendingCl
     modelCatalog: ClaudeModelCatalog = BUNDLED_CLAUDE_MODEL_CATALOG,
   ): Effect.fn.Return<ServerProviderDraft> {
     const checkedAt = yield* nowIso;
-    const models = providerModelsFromSettings(
+    const models = claudeProviderModels(
       modelCatalog.models.map((entry) => entry.model),
       claudeSettings.customModels,
-      DEFAULT_CLAUDE_MODEL_CAPABILITIES,
     );
 
     if (!claudeSettings.enabled) {
diff --git a/apps/server/src/provider/ProviderRegistry.test.ts b/apps/server/src/provider/ProviderRegistry.test.ts
index 93fec081ebb9c..974c13eae89be 100644
--- a/apps/server/src/provider/ProviderRegistry.test.ts
+++ b/apps/server/src/provider/ProviderRegistry.test.ts
@@ -3142,5 +3142,51 @@ it.layer(
         ),
       ),
     );
+
+    it.effect("advertises Ultracode as a toggle on custom models", () =>
+      Effect.gen(function* () {
+        const status = yield* checkClaudeProviderStatus(
+          {
+            ...defaultClaudeSettings,
+            customModels: [
+              {
+                slug: "claude-custom-tuned",
+                capabilities: {
+                  optionDescriptors: [
+                    {
+                      id: "effort",
+                      label: "Reasoning",
+                      type: "select",
+                      options: [
+                        { id: "high", label: "High", isDefault: true },
+                        { id: "ultracode", label: "Ultracode" },
+                      ],
+                    },
+                  ],
+                },
+              },
+            ],
+          },
+          claudeCapabilities(),
+        );
+        const custom = status.models.find((model) => model.slug === "claude-custom-tuned");
+        assert.deepStrictEqual(
+          custom?.capabilities?.optionDescriptors?.map((descriptor) =>
+            descriptor.type === "select"
+              ? `${descriptor.id}:${descriptor.options.map((option) => option.id).join("|")}`
+              : `${descriptor.id}:${descriptor.type}`,
+          ),
+          ["effort:high|xhigh", "ultracode:boolean"],
+        );
+      }).pipe(
+        Effect.provide(
+          layerMockSpawner((args) => {
+            const joined = args.join(" ");
+            if (joined === "--version") return { stdout: "1.0.0\n", stderr: "", code: 0 };
+            throw new Error(`Unexpected args: ${joined}`);
+          }),
+        ),
+      ),
+    );
   });
 });
diff --git a/apps/server/src/provider/model-manifest.json b/apps/server/src/provider/model-manifest.json
index 56398dcc9e756..8e8200f0983ba 100644
--- a/apps/server/src/provider/model-manifest.json
+++ b/apps/server/src/provider/model-manifest.json
@@ -1,6 +1,6 @@
 {
   "version": 1,
-  "updatedAt": "2026-11-02T21:16:47Z",
+  "updatedAt": "2026-11-03T18:04:02Z",
   "compatibility": [
     {
       "driver": "codex",
@@ -25,7 +25,7 @@
     {
       "driver": "claudeAgent",
       "t3CodeRange": ">=0.0.42",
-      "recommendedRange": ">=2.1.280",
+      "recommendedRange": ">=2.1.284",
       "ranges": [
         { "range": ">=2.1.280", "status": "supported" },
         { "range": ">=2.1.111 <2.1.280", "status": "graceful" },
diff --git a/apps/server/src/textGeneration/ClaudeTextGeneration.ts b/apps/server/src/textGeneration/ClaudeTextGeneration.ts
index 51acced2745e5..5cd0879f3b1b5 100644
--- a/apps/server/src/textGeneration/ClaudeTextGeneration.ts
+++ b/apps/server/src/textGeneration/ClaudeTextGeneration.ts
@@ -22,7 +22,6 @@ import {
   BUNDLED_CLAUDE_MODEL_CATALOG,
   type ClaudeModelCatalog,
   getClaudeCatalogModelCapabilities,
-  isClaudeCatalogUltracodeEffort,
   normalizeClaudeCatalogEffort,
   resolveClaudeCatalogApiModelId,
   resolveClaudeCatalogEffort,
@@ -163,7 +162,7 @@ export const makeClaudeTextGeneration = Effect.fn("makeClaudeTextGeneration")(fu
       resolvedEffort,
       resolvedModelSelection.model,
     );
-    const ultracode = isClaudeCatalogUltracodeEffort(resolvedEffort);
+    const ultracode = findDescriptor("ultracode")?.currentValue;
     const thinkingDescriptor = findDescriptor("thinking");
     const fastModeDescriptor = findDescriptor("fastMode");
     // Only a chosen value; otherwise Claude Code's own default applies, as in chat turns.
@@ -177,7 +176,7 @@ export const makeClaudeTextGeneration = Effect.fn("makeClaudeTextGeneration")(fu
       disableAllHooks: true,
       ...(typeof thinking === "boolean" ? { alwaysThinkingEnabled: thinking } : {}),
       ...(fastMode ? { fastMode: true } : {}),
-      ...(ultracode ? { ultracode: true } : {}),
+      ...(typeof ultracode === "boolean" ? { ultracode } : {}),
     };
     const settingsJson = yield* encodeJsonForOperation(
       operation,
diff --git a/apps/web/src/components/chat/ComposerModelEffort.tsx b/apps/web/src/components/chat/ComposerModelEffort.tsx
index 3a863936101b2..35fd11c98be7c 100644
--- a/apps/web/src/components/chat/ComposerModelEffort.tsx
+++ b/apps/web/src/components/chat/ComposerModelEffort.tsx
@@ -7,7 +7,7 @@ import {
 import type { ProviderOptionDescriptor, RuntimeMode } from "@t3tools/contracts";
 import type { EffortDisplay } from "@t3tools/contracts/settings";
 import { getProviderOptionCurrentLabel } from "@t3tools/shared/model";
-import { CheckIcon, ChevronRightIcon, ChevronUpIcon } from "lucide-react";
+import { CheckIcon, ChevronRightIcon, ChevronUpIcon, WorkflowIcon } from "lucide-react";
 import { type KeyboardEvent, type ReactNode, use, useRef, useState } from "react";
 
 import { cn } from "~/lib/utils";
@@ -36,7 +36,7 @@ import {
 type SelectDescriptor = Extract<ProviderOptionDescriptor, { type: "select" }>;
 type BooleanDescriptor = Extract<ProviderOptionDescriptor, { type: "boolean" }>;
 
-/** Codex service tiers and Claude's Fast mode share the footer's speed control. */
+/** Codex service tiers, Claude's Fast mode, and Ultracode sit in the footer, not the column. */
 function splitSpeed(
   provider: TraitsSelectionInput["provider"],
   selects: ReadonlyArray<SelectDescriptor>,
@@ -47,11 +47,15 @@ function splitSpeed(
       ? (selects.find((descriptor) => descriptor.id === "serviceTier") ?? null)
       : null;
   const fastToggle = toggles.find((descriptor) => descriptor.id === "fastMode") ?? null;
+  const ultracodeToggle = toggles.find((descriptor) => descriptor.id === "ultracode") ?? null;
   return {
     speedSelect,
     fastToggle,
+    ultracodeToggle,
     columnSelects: selects.filter((descriptor) => descriptor !== speedSelect),
-    columnToggles: toggles.filter((descriptor) => descriptor !== fastToggle),
+    columnToggles: toggles.filter(
+      (descriptor) => descriptor !== fastToggle && descriptor !== ultracodeToggle,
+    ),
   };
 }
 
@@ -79,7 +83,8 @@ function columnControls(
 
 /**
  * What the model trigger shows after the model name: the effort word (or bars, per the
- * Appearance setting), a bolt for Fast, and other traits such as a context window.
+ * Appearance setting), a bolt for Fast, a workflow icon for Ultracode, and other traits such as a
+ * context window.
  */
 export function describeComposerEffort(
   traits: TraitsSelectionInput | null,
@@ -135,7 +140,8 @@ export function describeComposerEffort(
       modelSelection,
       traits.reportedModelSelection,
     );
-  if (!word && !glyph && !fast && !contextWindow) return { suffix: null, detail: display.label };
+  if (!word && !glyph && !fast && !display.ultracode && !contextWindow)
+    return { suffix: null, detail: display.label };
   return {
     detail: display.label,
     suffix: (
@@ -154,6 +160,9 @@ export function describeComposerEffort(
           <EffortGlyph count={glyph.count} filled={glyph.filled} size={size} />
         ) : null}
         {fast ? <FastBolt ultra={display.speedLabel === "Ultrafast"} /> : null}
+        {display.ultracode ? (
+          <WorkflowIcon aria-hidden="true" data-composer-control-icon className="size-3" />
+        ) : null}
         {contextWindow ? (
           <span
             // A label, so icon-only footers drop it; compacted rows drop it before the model.
@@ -595,6 +604,31 @@ function SpeedControl(props: { traits: TraitsSelectionInput }) {
   );
 }
 
+function UltracodeControl(props: { traits: TraitsSelectionInput }) {
+  const traits = useTraitsSelection(props.traits);
+  const { ultracodeToggle } = splitSpeed(
+    props.traits.provider,
+    traits.selectDescriptors,
+    traits.booleanDescriptors,
+  );
+  if (traits.modelIsUnavailable || !ultracodeToggle) return null;
+  const on = ultracodeToggle.currentValue === true;
+  return (
+    <div className="flex rounded-lg bg-input/40 p-0.5">
+      <button
+        type="button"
+        aria-pressed={on}
+        data-checked={on || undefined}
+        className={FOOTER_SEGMENT}
+        onClick={() => traits.changeBoolean(ultracodeToggle.id, !on)}
+      >
+        <WorkflowIcon aria-hidden="true" className="size-3" />
+        {ultracodeToggle.label}
+      </button>
+    </div>
+  );
+}
+
 /** Permissions change rarely, so the footer names the mode and nests the choice in a menu. */
 function PermissionsMenu(props: {
   runtimeMode: RuntimeMode;
@@ -647,6 +681,7 @@ export function ComposerPickerFooter(props: {
   return (
     <div className="flex flex-wrap items-center gap-2 border-t border-border/70 bg-muted/40 px-3 py-2">
       {props.traits ? <SpeedControl traits={props.traits} /> : null}
+      {props.traits ? <UltracodeControl traits={props.traits} /> : null}
       <PermissionsMenu
         runtimeMode={props.runtimeMode}
         options={props.runtimeModeOptions}
diff --git a/apps/web/src/components/chat/EffortGlyph.tsx b/apps/web/src/components/chat/EffortGlyph.tsx
index 7614e41c496a6..ae90228b8da1b 100644
--- a/apps/web/src/components/chat/EffortGlyph.tsx
+++ b/apps/web/src/components/chat/EffortGlyph.tsx
@@ -10,7 +10,7 @@ const BASELINE_INSET = 2;
 
 type SelectDescriptor = Extract<ProviderOptionDescriptor, { type: "select" }>;
 
-// Ultracode changes the workflow, not only intensity, so it keeps its name like Ultrathink.
+// Older servers offer Ultracode as a level. It changes the workflow, so it keeps its name.
 // Max is named too, so the full scale stops short of it.
 const NAMED_LEVELS = new Set(["ultracode", "max"]);
 const OFF_LEVELS = new Set(["off", "none"]);
diff --git a/apps/web/src/components/chat/SubagentTooltipContent.tsx b/apps/web/src/components/chat/SubagentTooltipContent.tsx
index a965e89efd728..5b5f8b3477420 100644
--- a/apps/web/src/components/chat/SubagentTooltipContent.tsx
+++ b/apps/web/src/components/chat/SubagentTooltipContent.tsx
@@ -50,16 +50,16 @@ export function SubagentTooltipContent(props: {
   result?: string | null | undefined;
   progress?: string | null | undefined;
 }) {
-  const { modelLabel, workspace: metadata } = resolveSubagentMetadata(props);
-  const preview = subagentDetailPreview(props);
-  const model = props.model?.trim();
-  const modelSlug = props.provider
-    ? resolveSelectableModel(props.provider.driver, model, props.provider.models)
-    : model;
-  const providerModel = props.provider?.models.find((candidate) => candidate.slug === modelSlug);
   const childSelection =
     props.modelSelection ??
     (props.origin === "app_owned" ? props.childThread?.modelSelection : undefined);
+  const {
+    modelLabel,
+    modelSlug,
+    workspace: metadata,
+  } = resolveSubagentMetadata({ ...props, modelSelection: childSelection });
+  const preview = subagentDetailPreview(props);
+  const providerModel = props.provider?.models.find((candidate) => candidate.slug === modelSlug);
   const childModel = props.provider
     ? (resolveSelectableModel(
         props.provider.driver,
@@ -69,7 +69,7 @@ export function SubagentTooltipContent(props: {
     : childSelection?.model.trim();
   const provider = props.provider;
   const matchingSelection =
-    childModel === (modelSlug ?? model) && childSelection?.instanceId === props.providerInstanceId
+    childModel === modelSlug && childSelection?.instanceId === props.providerInstanceId
       ? childSelection
       : undefined;
   const effort = REASONING_EFFORT_OPTION_IDS.map((id) =>
diff --git a/apps/web/src/components/chat/ThreadLineageWorkflowRow.tsx b/apps/web/src/components/chat/ThreadLineageWorkflowRow.tsx
index 9d31ec35761e9..4cfb23350e912 100644
--- a/apps/web/src/components/chat/ThreadLineageWorkflowRow.tsx
+++ b/apps/web/src/components/chat/ThreadLineageWorkflowRow.tsx
@@ -1,6 +1,7 @@
-import type {
-  SubagentWorkflowGroup,
-  RuntimeSubagent,
+import {
+  workflowMemberModelSelection,
+  type SubagentWorkflowGroup,
+  type RuntimeSubagent,
 } from "@t3tools/client-runtime/state/subagentRuntime";
 import type { ProviderDriverKind, ProviderInstanceId, ServerProvider } from "@t3tools/contracts";
 import { ChevronDownIcon, SquareIcon } from "lucide-react";
@@ -101,6 +102,7 @@ function WorkflowMemberRow({
             model={member.model}
             providerInstanceId={providerInstanceId}
             origin="provider_native"
+            modelSelection={workflowMemberModelSelection(member, providerInstanceId)}
             provider={provider}
             providers={providers}
             driver={driver}
diff --git a/apps/web/src/components/chat/WorkflowOpeningBlock.tsx b/apps/web/src/components/chat/WorkflowOpeningBlock.tsx
index 3ab51f077e060..c6be9690e9940 100644
--- a/apps/web/src/components/chat/WorkflowOpeningBlock.tsx
+++ b/apps/web/src/components/chat/WorkflowOpeningBlock.tsx
@@ -1,6 +1,7 @@
 import { useAtomValue } from "@effect/atom-react";
 import {
   isTerminalSubagentStatus,
+  workflowMemberModelSelection,
   workflowOpeningHeadline,
   type RuntimeSubagent,
   type WorkflowOpening,
@@ -183,6 +184,7 @@ function WorkflowMemberRow(props: {
             model={member.model}
             providerInstanceId={props.providerInstanceId}
             origin="provider_native"
+            modelSelection={workflowMemberModelSelection(member, props.providerInstanceId)}
             provider={props.providers.find(
               (provider) => provider.instanceId === props.providerInstanceId,
             )}
diff --git a/packages/client-runtime/src/modelTraits.ts b/packages/client-runtime/src/modelTraits.ts
index b05f9226defb3..9a3dc06a15173 100644
--- a/packages/client-runtime/src/modelTraits.ts
+++ b/packages/client-runtime/src/modelTraits.ts
@@ -120,10 +120,12 @@ export function buildTraitsTriggerDisplay(input: {
   label: string;
   /** "Fast" or "Ultrafast" when a speed option is on. */
   speedLabel: string | null;
+  ultracode: boolean;
 } {
   let fastModeFallbackLabel: string | null = null;
   let speedLabel: string | null = null;
   let reasoningLabelIndex = -1;
+  let ultracodeLabelIndex = -1;
   const labels: Array<string> = [];
   for (const descriptor of input.descriptors) {
     if (descriptor.id === "fastMode" && descriptor.type === "boolean") {
@@ -131,6 +133,13 @@ export function buildTraitsTriggerDisplay(input: {
       fastModeFallbackLabel = speedLabel ?? "Normal";
       continue;
     }
+    if (descriptor.id === "ultracode" && descriptor.type === "boolean") {
+      if (descriptor.currentValue === true) {
+        ultracodeLabelIndex = labels.length;
+        labels.push(descriptor.label);
+      }
+      continue;
+    }
     if (
       input.provider === "codex" &&
       descriptor.id === "serviceTier" &&
@@ -173,8 +182,9 @@ export function buildTraitsTriggerDisplay(input: {
     }
   }
 
+  const ultracode = ultracodeLabelIndex >= 0;
   if (labels.length === 0 && fastModeFallbackLabel !== null) {
-    return { label: fastModeFallbackLabel, speedLabel };
+    return { label: fastModeFallbackLabel, speedLabel, ultracode };
   }
   if (speedLabel) {
     if (reasoningLabelIndex >= 0) {
@@ -183,5 +193,5 @@ export function buildTraitsTriggerDisplay(input: {
       labels.push(speedLabel);
     }
   }
-  return { label: labels.join(" · "), speedLabel };
+  return { label: labels.join(" · "), speedLabel, ultracode };
 }
diff --git a/packages/client-runtime/src/state/subagentDisplay.ts b/packages/client-runtime/src/state/subagentDisplay.ts
index 124c45e264f79..c0763fa4c2f41 100644
--- a/packages/client-runtime/src/state/subagentDisplay.ts
+++ b/packages/client-runtime/src/state/subagentDisplay.ts
@@ -1,4 +1,5 @@
 import type {
+  ModelSelection,
   OrchestrationV2TurnItemStatus,
   OrchestrationV2ThreadShell,
   OrchestrationProjectShell,
@@ -50,6 +51,7 @@ export function formatSubagentDisplayTitle(title: string): string {
 
 export function resolveSubagentMetadata(input: {
   readonly model: string | null;
+  readonly modelSelection?: Pick<ModelSelection, "model"> | undefined;
   readonly provider?: Pick<ServerProvider, "driver" | "models"> | null | undefined;
   readonly parentThread?:
     | Pick<OrchestrationV2ThreadShell, "projectId" | "worktreePath">
@@ -65,7 +67,7 @@ export function resolveSubagentMetadata(input: {
     | null
     | undefined;
 }) {
-  const model = input.model?.trim();
+  const model = input.model?.trim() || input.modelSelection?.model.trim();
   const slug = input.provider
     ? resolveSelectableModel(input.provider.driver, model, input.provider.models)
     : model;
@@ -108,7 +110,7 @@ export function resolveSubagentMetadata(input: {
         ]
       : []),
   ];
-  return { modelLabel, workspace };
+  return { modelLabel, modelSlug: slug ?? model ?? null, workspace };
 }
 
 export function subagentDetailPreview(input: {
diff --git a/packages/client-runtime/src/state/subagentRuntime.test.ts b/packages/client-runtime/src/state/subagentRuntime.test.ts
index c40c9fe42d81e..93d15b016d755 100644
--- a/packages/client-runtime/src/state/subagentRuntime.test.ts
+++ b/packages/client-runtime/src/state/subagentRuntime.test.ts
@@ -13,7 +13,10 @@ import {
   isWorkflowScriptMessage,
   projectedSubagentsToRuntime,
   resolveWorkflowOpening,
+  workflowMemberModelSelection,
 } from "./subagentRuntime.ts";
+import { resolveSubagentMetadata } from "./subagentDisplay.ts";
+import { formatSubagentEffort } from "./threadExecution.ts";
 
 const at = (iso: string) => DateTime.makeUnsafe(iso);
 
@@ -82,6 +85,42 @@ describe("projectedSubagentsToRuntime workflow expansion", () => {
     expect(settled?.speed).toBe("standard");
     expect(settled?.progress).toBe("Reply with exactly: A1");
     expect(settled?.usage).toEqual({ totalTokens: 71_141, toolUses: 3, durationMs: 1500 });
+    const instanceId = ProviderInstanceId.make("claudeAgent");
+    expect(workflowMemberModelSelection(settled!, instanceId)).toEqual({
+      instanceId,
+      model: "claude-opus-5[1m]",
+      options: [
+        { id: "effort", value: "xhigh" },
+        { id: "fastMode", value: false },
+      ],
+    });
+    expect(workflowMemberModelSelection({ model: null, effort: "xhigh" }, instanceId)).toBe(
+      undefined,
+    );
+    const provider = {
+      driver: ProviderDriverKind.make("claudeAgent"),
+      models: [
+        { slug: "claude-opus-5", name: "Claude Opus 5", isCustom: false, capabilities: null },
+      ],
+    };
+    const modelSelection = workflowMemberModelSelection(settled!, instanceId);
+    const { modelSlug } = resolveSubagentMetadata({
+      model: settled!.model,
+      modelSelection,
+      provider,
+    });
+    expect(formatSubagentEffort({ modelSlug, modelSelection, provider })).toBe("xhigh");
+  });
+
+  it("names a workflow by the model it runs on when the provider reports none", () => {
+    const [workflow] = projectedSubagentsToRuntime([subagent({ model: null })]);
+    expect(
+      resolveSubagentMetadata({
+        model: workflow!.model,
+        modelSelection: { model: "claude-opus-5-5" },
+      }).modelLabel,
+    ).toBe("Claude Opus 5.5");
+    expect(resolveSubagentMetadata({ model: workflow!.model }).modelLabel).toBe("Not reported");
   });
 
   it.each(["completed", "cancelled", "failed"] as const)(
diff --git a/packages/client-runtime/src/state/subagentRuntime.ts b/packages/client-runtime/src/state/subagentRuntime.ts
index e3807362fbdf6..fac58a029ce62 100644
--- a/packages/client-runtime/src/state/subagentRuntime.ts
+++ b/packages/client-runtime/src/state/subagentRuntime.ts
@@ -1,6 +1,7 @@
 import { groupBy } from "effect/Array";
 import * as DateTime from "effect/DateTime";
 import type {
+  ModelSelection,
   OrchestrationV2AppThread,
   OrchestrationV2Subagent,
   OrchestrationV2SubagentWorkflow,
@@ -175,6 +176,21 @@ function workflowMembersToRuntime(
   });
 }
 
+export function workflowMemberModelSelection(
+  member: Pick<RuntimeSubagent, "model" | "effort" | "speed">,
+  instanceId: ModelSelection["instanceId"],
+): ModelSelection | undefined {
+  if (!member.model) return undefined;
+  return {
+    instanceId,
+    model: member.model,
+    options: [
+      ...(member.effort ? [{ id: "effort", value: member.effort }] : []),
+      ...(member.speed ? [{ id: "fastMode", value: member.speed === "fast" }] : []),
+    ],
+  };
+}
+
 export function projectedSubagentsToRuntime(
   subagents: ReadonlyArray<{
     readonly id: string;
diff --git a/packages/client-runtime/src/state/threadExecution.test.ts b/packages/client-runtime/src/state/threadExecution.test.ts
index ed60963ce7ef2..fd03b06b32017 100644
--- a/packages/client-runtime/src/state/threadExecution.test.ts
+++ b/packages/client-runtime/src/state/threadExecution.test.ts
@@ -14,6 +14,7 @@ import {
   type OrchestrationV2RunStatus,
 } from "@t3tools/contracts";
 import * as DateTime from "effect/DateTime";
+import { createModelCapabilities, createModelSelection } from "@t3tools/shared/model";
 import { usageLimitBlockedRun } from "@t3tools/shared/orchestrationV2ThreadError";
 import { describe, expect, it } from "vite-plus/test";
 
@@ -26,6 +27,7 @@ import {
   deriveRunlessWorkStartedAt,
   deriveThreadActivityRun,
   deriveThreadRuntime,
+  formatModelSelectionEffort,
   isBackgroundWorkStopPending,
   presentPendingBackgroundWork,
   presentProviderGoal,
@@ -473,6 +475,39 @@ describe("provider-reported model selection", () => {
   });
 });
 
+describe("formatModelSelectionEffort", () => {
+  it("labels an old Ultracode effort by the effort it runs at", () => {
+    const models = [
+      {
+        slug: "claude-opus-5-5",
+        name: "Claude Opus 5.5",
+        isCustom: false,
+        capabilities: createModelCapabilities({
+          optionDescriptors: [
+            {
+              id: "effort",
+              label: "Reasoning",
+              type: "select",
+              options: [
+                { id: "high", label: "High", isDefault: true },
+                { id: "xhigh", label: "Extra High" },
+              ],
+            },
+            { id: "ultracode", label: "Ultracode", type: "boolean" },
+          ],
+        }),
+      },
+    ];
+    const selection = createModelSelection(
+      ProviderInstanceId.make("claudeAgent"),
+      "claude-opus-5-5",
+      [{ id: "effort", value: "ultracode" }],
+    );
+
+    expect(formatModelSelectionEffort(selection, models)).toBe("Extra High");
+  });
+});
+
 describe("isBackgroundWorkStopPending", () => {
   const tasks = [{ taskId: "dev-server" }];
   const sent = { threadKey: "env:thread", taskIds: ["dev-server"], retryAt: null };
diff --git a/packages/client-runtime/src/state/threadExecution.ts b/packages/client-runtime/src/state/threadExecution.ts
index b6151c7c875be..f4335256e98fb 100644
--- a/packages/client-runtime/src/state/threadExecution.ts
+++ b/packages/client-runtime/src/state/threadExecution.ts
@@ -13,6 +13,7 @@ import {
   type OrchestrationV2NotificationSource,
   type OrchestrationV2PendingBackgroundTask,
   type OrchestrationV2ProviderGoal,
+  type ServerProvider,
   type ServerProviderModel,
   type OrchestrationV2ExecutionNode,
   type OrchestrationV2ThreadProjection,
@@ -24,7 +25,13 @@ import {
   backgroundWorkHoldsCompletion,
   derivePendingBackgroundWork,
 } from "@t3tools/shared/orchestrationV2PendingBackgroundWork";
-import { getProviderOptionCurrentLabel, getProviderOptionStatedValue } from "@t3tools/shared/model";
+import {
+  getModelSelectionStringOptionValue,
+  getProviderOptionCurrentLabel,
+  getProviderOptionStatedValue,
+  resolveSelectableModel,
+  withLegacyUltracodeEffort,
+} from "@t3tools/shared/model";
 import { formatDuration } from "@t3tools/shared/orchestrationTiming";
 import * as DateTime from "effect/DateTime";
 
@@ -164,16 +171,18 @@ export function formatModelSelectionEffort(
 ): string | null {
   const caps = models.find((model) => model.slug === selection.model)?.capabilities;
   if (!caps) return null;
+  const options = withLegacyUltracodeEffort(caps.optionDescriptors, selection.options);
+  const current = options ? { ...selection, options } : selection;
   for (const id of REASONING_EFFORT_OPTION_IDS) {
     const descriptor = caps.optionDescriptors?.find((candidate) => candidate.id === id);
     if (descriptor?.type !== "select") continue;
-    const value = getProviderOptionStatedValue(id, selection, reportedSelection);
+    const value = getProviderOptionStatedValue(id, current, reportedSelection);
     if (value === undefined && id !== "variant") continue;
     if (typeof value === "boolean") continue;
     // Bypass picker normalization so an obsolete choice cannot become a catalog default.
     const label = getProviderOptionCurrentLabel(
       { ...descriptor, currentValue: value },
-      selection,
+      current,
       reportedSelection,
     );
     if (label) return label;
@@ -181,6 +190,28 @@ export function formatModelSelectionEffort(
   return null;
 }
 
+/** A reported model the picker catalog does not know, such as `claude-opus-5[1m]`, keeps its raw effort. */
+export function formatSubagentEffort(input: {
+  readonly modelSlug: string | null;
+  readonly modelSelection: ModelSelection | undefined;
+  readonly provider: Pick<ServerProvider, "driver" | "models"> | undefined;
+}): string | null {
+  const { modelSlug, modelSelection: selection, provider } = input;
+  if (!provider || !selection || !modelSlug) return null;
+  const selectionSlug =
+    resolveSelectableModel(provider.driver, selection.model, provider.models) ??
+    selection.model.trim();
+  if (selectionSlug !== modelSlug) return null;
+  if (provider.models.some((model) => model.slug === modelSlug)) {
+    return formatModelSelectionEffort({ ...selection, model: modelSlug }, provider.models);
+  }
+  return (
+    REASONING_EFFORT_OPTION_IDS.map((id) => getModelSelectionStringOptionValue(selection, id)).find(
+      Boolean,
+    ) ?? null
+  );
+}
+
 const SUBAGENT_STATUS_LABELS: Record<OrchestrationV2ExecutionNode["status"], string> = {
   idle: "Idle",
   pending: "Working",
diff --git a/packages/shared/src/model.test.ts b/packages/shared/src/model.test.ts
index 396d4d9c86c26..af6af0254a94d 100644
--- a/packages/shared/src/model.test.ts
+++ b/packages/shared/src/model.test.ts
@@ -50,6 +50,32 @@ describe("descriptor helpers", () => {
     ).toEqual([{ id: "fastMode", value: true }]);
   });
 
+  it("dispatches an old Ultracode effort as Extra High with the Ultracode toggle", () => {
+    const legacy = [{ id: "effort", value: "ultracode" }];
+    const descriptors = getProviderOptionDescriptors({
+      caps: createModelCapabilities({
+        optionDescriptors: [
+          {
+            id: "effort",
+            label: "Reasoning",
+            type: "select",
+            options: [
+              { id: "high", label: "High", isDefault: true },
+              { id: "xhigh", label: "Extra High" },
+            ],
+          },
+          { id: "ultracode", label: "Ultracode", type: "boolean" },
+        ],
+      }),
+      selections: legacy,
+    });
+
+    expect(buildExplicitProviderOptionSelectionsFromDescriptors(descriptors, legacy)).toEqual([
+      { id: "effort", value: "xhigh" },
+      { id: "ultracode", value: true },
+    ]);
+  });
+
   it("compares complete model selections independent of option ordering", () => {
     const left = createModelSelection(ProviderInstanceId.make("codex"), "gpt-5.4", [
       { id: "reasoningEffort", value: "high" },
diff --git a/packages/shared/src/model.ts b/packages/shared/src/model.ts
index 51cc1430321d8..0fdb2bc71ec4f 100644
--- a/packages/shared/src/model.ts
+++ b/packages/shared/src/model.ts
@@ -196,12 +196,40 @@ function withDescriptorCurrentValue(
   };
 }
 
+// Ultracode was a Claude effort level before it became its own toggle; that level ran at xhigh.
+export function withLegacyUltracodeEffort<
+  Selections extends ReadonlyArray<ProviderOptionSelection> | null | undefined,
+>(
+  descriptors: ReadonlyArray<ProviderOptionDescriptor> | null | undefined,
+  selections: Selections,
+): Selections | Array<ProviderOptionSelection> {
+  if (
+    getRawSelectionValueById(selections, "effort") !== "ultracode" ||
+    !descriptors?.some(
+      (descriptor) => descriptor.id === "ultracode" && descriptor.type === "boolean",
+    )
+  ) {
+    return selections;
+  }
+  return [
+    ...(selections ?? []).map((selection) =>
+      selection.id === "effort" && selection.value === "ultracode"
+        ? { id: "effort", value: "xhigh" }
+        : selection,
+    ),
+    ...(getRawSelectionValueById(selections, "ultracode") === undefined
+      ? [{ id: "ultracode", value: true }]
+      : []),
+  ];
+}
+
 export function getProviderOptionDescriptors(input: {
   caps: ModelCapabilities;
   selections?: ReadonlyArray<ProviderOptionSelection> | null | undefined;
 }): ReadonlyArray<ProviderOptionDescriptor> {
-  const { caps, selections } = input;
+  const { caps } = input;
   const baseDescriptors = (caps.optionDescriptors ?? []).map(cloneDescriptor);
+  const selections = withLegacyUltracodeEffort(baseDescriptors, input.selections);
 
   return baseDescriptors.map((descriptor) =>
     withDescriptorCurrentValue(
@@ -312,7 +340,9 @@ export function buildExplicitProviderOptionSelectionsFromDescriptors(
   if (!selections || selections.length === 0) {
     return undefined;
   }
-  const explicitIds = new Set(selections.map((selection) => selection.id));
+  const explicitIds = new Set(
+    withLegacyUltracodeEffort(descriptors, selections).map(({ id }) => id),
+  );
   const normalized = buildProviderOptionSelectionsFromDescriptors(descriptors)?.filter(
     (selection) => explicitIds.has(selection.id),
   );