diff --git a/src/providers/xai-transport.ts b/src/providers/xai-transport.ts
index 76582b07298..cc96f67a75b 100644
--- a/src/providers/xai-transport.ts
+++ b/src/providers/xai-transport.ts
@@ -28,8 +28,8 @@ export function isXaiResponsesDestination(provider: Pick<OcxProviderConfig, "bas
 }
 
 export const XAI_GROK_COMPATIBILITY = {
-  version: "0.2.93",
-  userAgent: "opencodex-grok/0.2.93",
+  version: "1.0.25",
+  userAgent: "opencodex-grok/1.0.25",
   headers: {
     clientIdentifier: "x-grok-client-identifier",
     clientVersion: "x-grok-client-version",
diff --git a/tests/providers/xai/xai-transport.test.ts b/tests/providers/xai/xai-transport.test.ts
index 263a1c049df..9bfd8d34509 100644
--- a/tests/providers/xai/xai-transport.test.ts
+++ b/tests/providers/xai/xai-transport.test.ts
@@ -533,16 +533,16 @@ async function capture(authMode: "oauth" | "key", calls = 1) {
 }
 
 describe("xAI outbound compatibility headers", () => {
-  test("OAuth snapshot is exact", async () => {
+  test("OAuth snapshot pins Grok CLI compatibility to 1.0.25", async () => {
     const { effective, seen } = await capture("oauth");
     expect(effective.baseUrl).toBe(XAI_GROK_CLI_BASE_URL);
     expect(lower(seen[0])).toEqual({
       authorization: "Bearer oauth-token",
       "content-type": "application/json",
-      "user-agent": `opencodex-grok/${XAI_GROK_CLIENT_VERSION}`,
+      "user-agent": "opencodex-grok/1.0.25",
       "x-authenticateresponse": "authenticate-response",
       "x-grok-client-identifier": "opencodex",
-      "x-grok-client-version": XAI_GROK_CLIENT_VERSION,
+      "x-grok-client-version": "1.0.25",
       "x-grok-conv-id": deriveXaiConvId("codex-session-abc"),
       "x-grok-req-id": expect.stringMatching(UUID_V4),
       "x-grok-session-id": deriveXaiConvId("codex-session-abc"),
@@ -557,7 +557,7 @@ describe("xAI outbound compatibility headers", () => {
     expect(lower(seen[0])).toEqual({
       authorization: "Bearer xai-api-key",
       "content-type": "application/json",
-      "user-agent": `opencodex-grok/${XAI_GROK_CLIENT_VERSION}`,
+      "user-agent": "opencodex-grok/1.0.25",
       "x-grok-conv-id": deriveXaiConvId("codex-session-abc"),
       "x-grok-req-id": expect.stringMatching(UUID_V4),
       "x-grok-session-id": deriveXaiConvId("codex-session-abc"),