diff --git a/open-sse/executors/antigravity.ts b/open-sse/executors/antigravity.ts
index 5489e9fbb9..494d750836 100644
--- a/open-sse/executors/antigravity.ts
+++ b/open-sse/executors/antigravity.ts
@@ -87,6 +87,9 @@ const ANTIGRAVITY_TRANSIENT_STATUSES = new Set([
   HTTP_STATUS.SERVICE_UNAVAILABLE,
   HTTP_STATUS.GATEWAY_TIMEOUT,
 ]);
+const ANTIGRAVITY_UNSUPPORTED_SAFETY_CATEGORIES = new Set<string>([
+  "HARM_CATEGORY_CIVIC_INTEGRITY",
+]);
 // The upstream API uses plain model IDs (no -high/-low suffix).
 // Tier suffixes were speculative and caused 404 for gemini-3.x models — the
 // bare-Pro→Low normalization was retired (the set stayed empty, making the guard
@@ -440,6 +443,14 @@ function asRecord(value: unknown): Record<string, unknown> | null {
     : null;
 }
 
+function getAntigravitySafetySettings(safetySettings: unknown): unknown[] {
+  const source = Array.isArray(safetySettings) ? safetySettings : DEFAULT_SAFETY_SETTINGS;
+  return source.filter((setting) => {
+    const category = asRecord(setting)?.category;
+    return typeof category !== "string" || !ANTIGRAVITY_UNSUPPORTED_SAFETY_CATEGORIES.has(category);
+  });
+}
+
 function sanitizeAntigravityGeminiRequest(
   request: Record<string, unknown>
 ): Record<string, unknown> {
@@ -687,12 +698,10 @@ export class AntigravityExecutor extends BaseExecutor {
         credentials,
         typeof normalizedRequest?.sessionId === "string" ? normalizedRequest.sessionId : undefined
       ),
-      // #5003: default to all-OFF safety for parity with the native Gemini paths
-      // (claude-to-gemini / openai-to-gemini both default to DEFAULT_SAFETY_SETTINGS).
-      // Previously this was `undefined`, which JSON.stringify drops, so Google Cloud Code
-      // applied its server-side defaults that false-flag benign technical prompts as
-      // `prohibited_content` (HTTP 200 + blocked body → terminal combo failover).
-      safetySettings: normalizedRequest?.safetySettings ?? DEFAULT_SAFETY_SETTINGS,
+      // #5003: send explicit all-OFF safety entries that Cloud Code accepts. Omitting the
+      // field lets Cloud Code apply server-side defaults that false-flag benign technical
+      // prompts as `prohibited_content`.
+      safetySettings: getAntigravitySafetySettings(normalizedRequest?.safetySettings),
       toolConfig:
         Array.isArray(normalizedRequest?.tools) && normalizedRequest.tools.length > 0
           ? { functionCallingConfig: { mode: "VALIDATED" } }
@@ -700,7 +709,9 @@ export class AntigravityExecutor extends BaseExecutor {
     };
 
     const transformedRequest = isClaude
-      ? stripTrailingAntigravityAssistantTurn(sanitizeAntigravityGeminiRequest(rawTransformedRequest))
+      ? stripTrailingAntigravityAssistantTurn(
+          sanitizeAntigravityGeminiRequest(rawTransformedRequest)
+        )
       : rawTransformedRequest;
 
     // Obfuscate sensitive client names in user content (e.g. "OpenCode", "Cursor")
diff --git a/open-sse/translator/request/openai-to-gemini.ts b/open-sse/translator/request/openai-to-gemini.ts
index 15aea48194..2d3fb8811f 100644
--- a/open-sse/translator/request/openai-to-gemini.ts
+++ b/open-sse/translator/request/openai-to-gemini.ts
@@ -633,6 +633,7 @@ function wrapInCloudCodeEnvelope(model, cloudCodeRequest, credentials = null) {
       systemInstruction: cloudCodeRequest.systemInstruction,
       generationConfig: applyAntigravityGenerationDefaults(cloudCodeRequest.generationConfig),
       tools: cloudCodeRequest.tools,
+      safetySettings: cloudCodeRequest.safetySettings,
     },
     model: cleanModel,
     userAgent: getAntigravityEnvelopeUserAgent(credentials),
diff --git a/tests/unit/antigravity-safetysettings-5003.test.ts b/tests/unit/antigravity-safetysettings-5003.test.ts
index 152a5eb3ff..f4cc058d15 100644
--- a/tests/unit/antigravity-safetysettings-5003.test.ts
+++ b/tests/unit/antigravity-safetysettings-5003.test.ts
@@ -3,13 +3,14 @@ import assert from "node:assert/strict";
 
 import { AntigravityExecutor } from "../../open-sse/executors/antigravity.ts";
 import { DEFAULT_SAFETY_SETTINGS } from "../../open-sse/translator/helpers/geminiHelper.ts";
+import { openaiToAntigravityRequest } from "../../open-sse/translator/request/openai-to-gemini.ts";
 
 // Regression for #5003: the Antigravity (Google Cloud Code) request builder explicitly set
 // `safetySettings: undefined`, which `JSON.stringify` drops entirely. With no safetySettings
 // reaching Cloud Code, Google applies its server-side safety defaults that false-flag benign
 // technical prompts as `prohibited_content` (HTTP 200 with a blocked body that combo failover
-// treats as terminal). The native Gemini paths all default to all-OFF
-// (DEFAULT_SAFETY_SETTINGS); Antigravity must match for parity.
+// treats as terminal). Antigravity still needs explicit all-OFF safety settings,
+// but Cloud Code rejects HARM_CATEGORY_CIVIC_INTEGRITY on the v1internal endpoint.
 
 test("transformRequest defaults safetySettings to all-OFF when none supplied (#5003)", async () => {
   const executor = new AntigravityExecutor();
@@ -26,17 +27,21 @@ test("transformRequest defaults safetySettings to all-OFF when none supplied (#5
 
   if (result instanceof Response) throw new Error("Unexpected Response from transformRequest");
   const innerRequest = result.request as Record<string, unknown>;
+  const antigravitySafetySettings = DEFAULT_SAFETY_SETTINGS.filter(
+    (setting) => setting.category !== "HARM_CATEGORY_CIVIC_INTEGRITY"
+  );
   assert.deepEqual(
     innerRequest.safetySettings,
-    DEFAULT_SAFETY_SETTINGS,
-    "safetySettings must default to all-OFF for parity with native Gemini paths"
+    antigravitySafetySettings,
+    "safetySettings must default to all-OFF entries accepted by Cloud Code"
   );
 });
 
-test("transformRequest honors a caller-supplied safetySettings (#5003)", async () => {
+test("transformRequest honors caller-supplied safetySettings accepted by Cloud Code (#5003)", async () => {
   const executor = new AntigravityExecutor();
   const callerSafety = [
     { category: "HARM_CATEGORY_HATE_SPEECH", threshold: "BLOCK_MEDIUM_AND_ABOVE" },
+    { category: "HARM_CATEGORY_CIVIC_INTEGRITY", threshold: "OFF" },
   ];
   const body = {
     request: {
@@ -54,7 +59,34 @@ test("transformRequest honors a caller-supplied safetySettings (#5003)", async (
   const innerRequest = result.request as Record<string, unknown>;
   assert.deepEqual(
     innerRequest.safetySettings,
-    callerSafety,
-    "a caller-supplied safetySettings must not be clobbered"
+    [{ category: "HARM_CATEGORY_HATE_SPEECH", threshold: "BLOCK_MEDIUM_AND_ABOVE" }],
+    "caller-supplied safetySettings should preserve accepted entries and drop rejected ones"
   );
 });
+
+test("OpenAI Antigravity translation preserves caller-supplied safetySettings (#5003)", async () => {
+  const executor = new AntigravityExecutor();
+  const callerSafety = [
+    { category: "HARM_CATEGORY_HATE_SPEECH", threshold: "BLOCK_MEDIUM_AND_ABOVE" },
+    { category: "HARM_CATEGORY_CIVIC_INTEGRITY", threshold: "OFF" },
+  ];
+  const translated = openaiToAntigravityRequest(
+    "gemini-2.5-flash",
+    {
+      messages: [{ role: "user", content: "hi" }],
+      safetySettings: callerSafety,
+    },
+    true,
+    { projectId: "project-1" }
+  );
+
+  const result = await executor.transformRequest("antigravity/gemini-2.5-flash", translated, true, {
+    projectId: "project-1",
+  });
+
+  if (result instanceof Response) throw new Error("Unexpected Response from transformRequest");
+  const innerRequest = result.request as Record<string, unknown>;
+  assert.deepEqual(innerRequest.safetySettings, [
+    { category: "HARM_CATEGORY_HATE_SPEECH", threshold: "BLOCK_MEDIUM_AND_ABOVE" },
+  ]);
+});