diff --git a/docs/providers/openai.md b/docs/providers/openai.md
index eb78c857524..5caf40dcd7e 100644
--- a/docs/providers/openai.md
+++ b/docs/providers/openai.md
@@ -179,7 +179,9 @@ Choose your preferred auth method and follow the setup steps.
     `chat-latest` is a moving alias. OpenAI documents it as the latest Instant
     model used in ChatGPT and recommends `gpt-5.5` for production API usage, so
     keep `openai/gpt-5.5` as the stable default unless you explicitly want that
-    alias behavior.
+    alias behavior. The alias currently accepts only `medium` text verbosity, so
+    OpenClaw normalizes incompatible OpenAI text-verbosity overrides for this
+    model.
 
     <Warning>
     OpenClaw does **not** expose `openai/gpt-5.3-codex-spark`. Live OpenAI API requests reject that model, and the current Codex catalog does not expose it either.
diff --git a/extensions/openai/openai-provider.live.test.ts b/extensions/openai/openai-provider.live.test.ts
index 8974da7e146..ab98fa058c6 100644
--- a/extensions/openai/openai-provider.live.test.ts
+++ b/extensions/openai/openai-provider.live.test.ts
@@ -17,6 +17,7 @@ type LiveModelCase = {
   contextWindow: number;
   maxTokens: number;
   reasoning: boolean;
+  textVerbosity: "low" | "medium";
 };
 
 function findOpenAIModel(modelId: string): Model<Api> | null {
@@ -34,6 +35,7 @@ function resolveLiveModelCase(modelId: string): LiveModelCase {
         contextWindow: 400_000,
         maxTokens: 128_000,
         reasoning: false,
+        textVerbosity: "medium",
       };
     case "gpt-5.5":
       return {
@@ -44,6 +46,7 @@ function resolveLiveModelCase(modelId: string): LiveModelCase {
         contextWindow: 1_000_000,
         maxTokens: 128_000,
         reasoning: true,
+        textVerbosity: "low",
       };
     case "gpt-5.5-pro":
       return {
@@ -54,6 +57,7 @@ function resolveLiveModelCase(modelId: string): LiveModelCase {
         contextWindow: 1_000_000,
         maxTokens: 128_000,
         reasoning: true,
+        textVerbosity: "low",
       };
     case "gpt-5.4":
       return {
@@ -64,6 +68,7 @@ function resolveLiveModelCase(modelId: string): LiveModelCase {
         contextWindow: 400_000,
         maxTokens: 128_000,
         reasoning: true,
+        textVerbosity: "low",
       };
     case "gpt-5.4-pro":
       return {
@@ -74,6 +79,7 @@ function resolveLiveModelCase(modelId: string): LiveModelCase {
         contextWindow: 400_000,
         maxTokens: 128_000,
         reasoning: true,
+        textVerbosity: "low",
       };
     case "gpt-5.4-mini":
       return {
@@ -84,6 +90,7 @@ function resolveLiveModelCase(modelId: string): LiveModelCase {
         contextWindow: 400_000,
         maxTokens: 128_000,
         reasoning: true,
+        textVerbosity: "low",
       };
     case "gpt-5.4-nano":
       return {
@@ -94,6 +101,7 @@ function resolveLiveModelCase(modelId: string): LiveModelCase {
         contextWindow: 400_000,
         maxTokens: 128_000,
         reasoning: true,
+        textVerbosity: "low",
       };
     default:
       throw new Error(`Unsupported live OpenAI model: ${modelId}`);
@@ -177,7 +185,7 @@ describeLive("buildOpenAIProvider live", () => {
         input: "Return exactly OK.",
         max_output_tokens: 64,
         ...(liveCase.reasoning ? { reasoning: { effort: "none" as const } } : {}),
-        text: { verbosity: "low" },
+        text: { verbosity: liveCase.textVerbosity },
       });
 
       expect(response.output_text.trim()).toMatch(/^OK[.!]?$/);
diff --git a/extensions/openai/openai-provider.test.ts b/extensions/openai/openai-provider.test.ts
index 060f0513b27..a3fdf919755 100644
--- a/extensions/openai/openai-provider.test.ts
+++ b/extensions/openai/openai-provider.test.ts
@@ -587,6 +587,40 @@ describe("buildOpenAIProvider", () => {
     expect(result.payload.tools).toEqual([{ type: "web_search" }]);
   });
 
+  it("clamps chat-latest text verbosity to the only live-supported value", () => {
+    const provider = buildOpenAIProvider();
+    const wrap = provider.wrapStreamFn;
+    expect(wrap).toBeTypeOf("function");
+    if (!wrap) {
+      throw new Error("expected OpenAI wrapper");
+    }
+    const extraParams = provider.prepareExtraParams?.({
+      provider: "openai",
+      modelId: "chat-latest",
+      extraParams: {
+        textVerbosity: "low",
+      },
+    } as never);
+    const result = runWrappedPayloadCase({
+      wrap,
+      provider: "openai",
+      modelId: "chat-latest",
+      extraParams: extraParams ?? undefined,
+      model: {
+        api: "openai-responses",
+        provider: "openai",
+        id: "chat-latest",
+        baseUrl: "https://api.openai.com/v1",
+        contextWindow: 400_000,
+      } as Model<"openai-responses">,
+      payload: {
+        text: { verbosity: "high" },
+      },
+    });
+
+    expect(result.payload.text).toEqual({ verbosity: "medium" });
+  });
+
   it("uses native OpenAI web search instead of the managed web_search function", () => {
     const provider = buildOpenAIProvider();
     const wrap = provider.wrapStreamFn;
diff --git a/extensions/openai/openai-provider.ts b/extensions/openai/openai-provider.ts
index f5e073ef533..a3d9e6e84f2 100644
--- a/extensions/openai/openai-provider.ts
+++ b/extensions/openai/openai-provider.ts
@@ -1,3 +1,4 @@
+import type { StreamFn } from "@mariozechner/pi-agent-core";
 import {
   type ProviderResolveDynamicModelContext,
   type ProviderRuntimeModel,
@@ -77,6 +78,42 @@ const OPENAI_MODERN_MODEL_IDS = [
   OPENAI_GPT_54_NANO_MODEL_ID,
   "gpt-5.2",
 ] as const;
+
+function clampChatLatestTextVerbosity(payload: unknown): void {
+  if (!payload || typeof payload !== "object") {
+    return;
+  }
+  const payloadObj = payload as Record<string, unknown>;
+  const text = payloadObj.text;
+  if (!text || typeof text !== "object") {
+    return;
+  }
+  const textObj = text as Record<string, unknown>;
+  if (textObj.verbosity !== undefined && textObj.verbosity !== "medium") {
+    payloadObj.text = { ...textObj, verbosity: "medium" };
+  }
+}
+
+function createOpenAIChatLatestCompatWrapper(baseStreamFn: StreamFn, modelId: string): StreamFn {
+  const underlying = baseStreamFn;
+  return (model, context, options) => {
+    if (
+      model.api !== "openai-responses" ||
+      normalizeLowercaseStringOrEmpty(modelId) !== OPENAI_CHAT_LATEST_MODEL_ID
+    ) {
+      return underlying(model, context, options);
+    }
+    const originalOnPayload = options?.onPayload;
+    return underlying(model, context, {
+      ...options,
+      onPayload: (payload) => {
+        clampChatLatestTextVerbosity(payload);
+        return originalOnPayload?.(payload, model);
+      },
+    });
+  };
+}
+
 function shouldUseOpenAIResponsesTransport(params: {
   provider: string;
   api?: string | null;
@@ -210,6 +247,7 @@ function resolveOpenAIGptForwardCompatModel(ctx: ProviderResolveDynamicModelCont
 }
 
 export function buildOpenAIProvider(): ProviderPlugin {
+  const responsesHooks = buildOpenAIResponsesProviderHooks({ transport: "sse" });
   return {
     id: PROVIDER_ID,
     label: "OpenAI",
@@ -247,7 +285,12 @@ export function buildOpenAIProvider(): ProviderPlugin {
       shouldUseOpenAIResponsesTransport({ provider, api, baseUrl })
         ? { api: "openai-responses", baseUrl }
         : undefined,
-    ...buildOpenAIResponsesProviderHooks({ transport: "sse" }),
+    ...responsesHooks,
+    wrapStreamFn: (ctx) =>
+      createOpenAIChatLatestCompatWrapper(
+        responsesHooks.wrapStreamFn?.(ctx) ?? ctx.streamFn,
+        ctx.modelId,
+      ),
     matchesContextOverflowError: ({ errorMessage }) =>
       /content_filter.*(?:prompt|input).*(?:too long|exceed)/i.test(errorMessage),
     resolveReasoningOutputMode: () => "native",