diff --git a/src/shared/constants/cliTools.js b/src/shared/constants/cliTools.js
index 1e58918aac..35e1bf0397 100644
--- a/src/shared/constants/cliTools.js
+++ b/src/shared/constants/cliTools.js
@@ -10,6 +10,9 @@ export const MITM_TOOLS = {
     mitmDomain: "daily-cloudcode-pa.googleapis.com",
     modelAliases: ["gemini-3.7-flash-high", "gemini-3.7-flash-medium", "gemini-3.7-flash-low", "gemini-3.6-flash-high", "gemini-3.6-flash-medium", "gemini-3.6-flash-low", "gemini-3.5-flash-low", "gemini-3-flash-agent", "gemini-3.5-flash-extra-low", "gemini-3.1-pro-low", "gemini-pro-agent", "claude-sonnet-4-6", "claude-opus-4-6-thinking", "gpt-oss-120b-medium", "gemini-3-flash"],
     defaultModels: [
+      { id: "gemini-3.7-flash-high", name: "Gemini 3.7 Flash (High)", alias: "gemini-3.7-flash-high" },
+      { id: "gemini-3.7-flash-medium", name: "Gemini 3.7 Flash (Medium)", alias: "gemini-3.7-flash-medium" },
+      { id: "gemini-3.7-flash-low", name: "Gemini 3.7 Flash (Low)", alias: "gemini-3.7-flash-low" },
       { id: "gemini-3.6-flash-high", name: "Gemini 3.6 Flash (High)", alias: "gemini-3.6-flash-high" },
       { id: "gemini-3.6-flash-medium", name: "Gemini 3.6 Flash (Medium)", alias: "gemini-3.6-flash-medium" },
       { id: "gemini-3.6-flash-low", name: "Gemini 3.6 Flash (Low)", alias: "gemini-3.6-flash-low" },
diff --git a/tests/unit/gemini-37-integration.test.js b/tests/unit/gemini-37-integration.test.js
new file mode 100644
index 0000000000..ed842d6fac
--- /dev/null
+++ b/tests/unit/gemini-37-integration.test.js
@@ -0,0 +1,100 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { createRequire } from "node:module";
+import { readFileSync } from "node:fs";
+import { fileURLToPath } from "node:url";
+import { dirname, join } from "node:path";
+
+import { getModelUpstreamId } from "../../open-sse/config/providerModels.js";
+import { AntigravityExecutor } from "../../open-sse/executors/antigravity.js";
+import { applyThinking, stripThinkingSuffix } from "../../open-sse/translator/concerns/thinkingUnified.js";
+import gemini from "../../open-sse/providers/registry/gemini.js";
+import { MODEL_PRICING } from "../../open-sse/providers/pricing.js";
+import { MITM_TOOLS } from "../../src/shared/constants/cliTools.js";
+
+const require = createRequire(import.meta.url);
+const mitmConfig = require("../../src/mitm/config.js");
+const here = dirname(fileURLToPath(import.meta.url));
+
+afterEach(() => {
+  vi.restoreAllMocks();
+});
+
+describe("Gemini 3.7 Antigravity tiers", () => {
+  it.each(["high", "medium", "low"])(
+    "maps the %s tier to the shared upstream model with matching thinking level",
+    (tier) => {
+      const publicModel = `gemini-3.7-flash-${tier}`;
+      const upstreamModel = getModelUpstreamId("ag", publicModel);
+      const body = {
+        model: stripThinkingSuffix(upstreamModel),
+        request: {
+          contents: [{ role: "user", parts: [{ text: "hello" }] }],
+          generationConfig: {},
+        },
+      };
+
+      applyThinking("antigravity", upstreamModel, body, "antigravity");
+      const finalBody = new AntigravityExecutor().transformRequest(
+        publicModel,
+        body,
+        true,
+        { projectId: "project", connectionId: "connection" }
+      );
+
+      expect(upstreamModel).toBe(`gemini-3.7-flash-tiered(${tier})`);
+      expect(finalBody.model).toBe("gemini-3.7-flash-tiered");
+      expect(finalBody.request.generationConfig.thinkingConfig).toEqual({
+        thinkingLevel: tier,
+        includeThoughts: true,
+      });
+    }
+  );
+});
+
+describe("Gemini 3.7 MITM model extraction", () => {
+  it.each(["high", "medium", "low"])("extracts the %s thinking tier for gemini-3.7-flash-tiered", (tier) => {
+    const body = Buffer.from(JSON.stringify({
+      request: { generationConfig: { thinkingConfig: { thinkingLevel: tier } } },
+    }));
+
+    expect(mitmConfig.extractModel(
+      "/v1internal/models/gemini-3.7-flash-tiered:streamGenerateContent",
+      body
+    )).toBe(`gemini-3.7-flash-${tier}`);
+  });
+
+  it("defaults invalid or missing thinking levels to medium", () => {
+    const body = Buffer.from(JSON.stringify({
+      request: { generationConfig: { thinkingConfig: { thinkingLevel: "unknown" } } },
+    }));
+
+    expect(mitmConfig.extractModel(
+      "/v1internal/models/gemini-3.7-flash-tiered:streamGenerateContent",
+      body
+    )).toBe("gemini-3.7-flash-medium");
+  });
+});
+
+describe("Gemini 3.7 MITM tools and catalog", () => {
+  it("includes gemini-3.7-flash tiers in MITM_TOOLS defaultModels", () => {
+    const defaultModelIds = MITM_TOOLS.antigravity.defaultModels.map((m) => m.id);
+    expect(defaultModelIds).toContain("gemini-3.7-flash-high");
+    expect(defaultModelIds).toContain("gemini-3.7-flash-medium");
+    expect(defaultModelIds).toContain("gemini-3.7-flash-low");
+  });
+
+  it("exposes the direct Gemini 3.7 API models and pricing", () => {
+    const ids = gemini.models.map((model) => model.id);
+    expect(ids).toContain("gemini-3.7-flash");
+    expect(MODEL_PRICING["gemini-3.7-flash"]).toMatchObject({ input: 1.5, output: 7.5 });
+  });
+
+  it("keeps the standalone CLI Antigravity catalog synchronized", () => {
+    const source = readFileSync(join(here, "../../cli/src/cli/menus/providers.js"), "utf8");
+    const agCatalog = source.match(/\n  ag: \[([\s\S]*?)\n  \],/)?.[1] || "";
+
+    expect(agCatalog).toContain("gemini-3.7-flash-high");
+    expect(agCatalog).toContain("gemini-3.7-flash-medium");
+    expect(agCatalog).toContain("gemini-3.7-flash-low");
+  });
+});