diff --git a/open-sse/config/agyModels.ts b/open-sse/config/agyModels.ts
index 51c4f60f22..14f9e0490c 100644
--- a/open-sse/config/agyModels.ts
+++ b/open-sse/config/agyModels.ts
@@ -106,6 +106,18 @@ export const AGY_PUBLIC_MODELS = Object.freeze([
     supportsVision: true,
     toolCalling: true,
   },
+  // Gemini 3.7 Flash: single callable public model (upstream exposes only
+  // gemini-3.7-flash-tiered; suffixed tier ids 404). One entry so it does not
+  // collide under the #3696 public-id uniqueness invariant.
+  {
+    id: "gemini-3.7-flash",
+    name: "Gemini 3.7 Flash",
+    contextLength: 1048576,
+    maxOutputTokens: 65536,
+    supportsReasoning: true,
+    supportsVision: true,
+    toolCalling: true,
+  },
   {
     id: "gemini-3.1-flash-lite",
     name: "Gemini 3.1 Flash Lite",
diff --git a/open-sse/config/antigravityModelAliases.ts b/open-sse/config/antigravityModelAliases.ts
index 80e066592d..eeacbdf8e3 100644
--- a/open-sse/config/antigravityModelAliases.ts
+++ b/open-sse/config/antigravityModelAliases.ts
@@ -124,6 +124,18 @@ export const ANTIGRAVITY_PUBLIC_MODELS = Object.freeze([
     supportsVision: true,
     toolCalling: true,
   },
+  // Gemini 3.7 Flash: Antigravity's live catalog exposes a single upstream id
+  // gemini-3.7-flash-tiered; the suffixed tier ids 404 upstream. Kept as one
+  // callable public model so it does not collide with the #3696 uniqueness invariant.
+  {
+    id: "gemini-3.7-flash",
+    name: "Gemini 3.7 Flash",
+    contextLength: 1048576,
+    maxOutputTokens: 65536,
+    supportsReasoning: true,
+    supportsVision: true,
+    toolCalling: true,
+  },
   {
     id: "gemini-3.1-flash-lite",
     name: "Gemini 3.1 Flash Lite",
@@ -163,6 +175,12 @@ export const ANTIGRAVITY_PUBLIC_MODELS = Object.freeze([
 ]);
 
 export const ANTIGRAVITY_MODEL_ALIASES = Object.freeze({
+  // Gemini 3.7 Flash: the live catalog (fetchAvailableModels on daily-cloudcode-pa)
+  // exposes a single upstream id `gemini-3.7-flash-tiered`; the agy CLI maps all
+  // display tiers (high/medium/low) to it. Verified 200 OK with thinking_level and
+  // thinkingBudget configs. The suffixed ids 404 upstream ("Requested entity was not found").
+  // Exposed as ONE callable model (see #3696: public ids must be unique upstream ids).
+  "gemini-3.7-flash": "gemini-3.7-flash-tiered",
   // gemini-3.1-pro-low is not aliased: the upstream accepts it verbatim.
   // gemini-3.1-pro-high: the discovery slot returns HTTP 400 on v1internal;
   // the live upstream id is gemini-pro-agent (see ANTIGRAVITY_PUBLIC_MODELS).
diff --git a/open-sse/config/freeModelCatalog.data.ts b/open-sse/config/freeModelCatalog.data.ts
index 3d43bdd020..78047f5299 100644
--- a/open-sse/config/freeModelCatalog.data.ts
+++ b/open-sse/config/freeModelCatalog.data.ts
@@ -26,6 +26,7 @@ export const FREE_MODEL_BUDGETS: FreeModelBudget[] = [
   { provider: "agy", modelId: "claude-sonnet-4-6", displayName: "Claude Sonnet 4.6 (Thinking)", monthlyTokens: 0, creditTokens: 0, freeType: "keyless", poolKey: "agy", tos: "avoid" },
   { provider: "agy", modelId: "gemini-3.1-pro-low", displayName: "Gemini 3.1 Pro (Low)", monthlyTokens: 0, creditTokens: 0, freeType: "keyless", poolKey: "agy", tos: "avoid" },
   { provider: "agy", modelId: "gemini-pro-agent", displayName: "Gemini 3.1 Pro (High)", monthlyTokens: 0, creditTokens: 0, freeType: "keyless", poolKey: "agy", tos: "avoid" },
+  { provider: "agy", modelId: "gemini-3.7-flash", displayName: "Gemini 3.7 Flash", monthlyTokens: 0, creditTokens: 0, freeType: "keyless", poolKey: "agy", tos: "avoid" },
   { provider: "agy", modelId: "gemini-3.6-flash-high", displayName: "Gemini 3.6 Flash (High)", monthlyTokens: 0, creditTokens: 0, freeType: "keyless", poolKey: "agy", tos: "avoid" },
   { provider: "agy", modelId: "gemini-3.6-flash-medium", displayName: "Gemini 3.6 Flash (Medium)", monthlyTokens: 0, creditTokens: 0, freeType: "keyless", poolKey: "agy", tos: "avoid" },
   { provider: "agy", modelId: "gemini-3.6-flash-low", displayName: "Gemini 3.6 Flash (Low)", monthlyTokens: 0, creditTokens: 0, freeType: "keyless", poolKey: "agy", tos: "avoid" },
diff --git a/open-sse/config/providers/registry/agy/index.ts b/open-sse/config/providers/registry/agy/index.ts
index 6aab7fe3d9..661f3f8ab7 100644
--- a/open-sse/config/providers/registry/agy/index.ts
+++ b/open-sse/config/providers/registry/agy/index.ts
@@ -25,4 +25,5 @@ export const agyProvider: RegistryEntry = {
   },
   models: [...AGY_PUBLIC_MODELS],
   passthroughModels: true,
+  liveCatalogAuthoritative: false,
 };
diff --git a/open-sse/config/providers/registry/antigravity/index.ts b/open-sse/config/providers/registry/antigravity/index.ts
index 74addaf815..c3080b0103 100644
--- a/open-sse/config/providers/registry/antigravity/index.ts
+++ b/open-sse/config/providers/registry/antigravity/index.ts
@@ -25,4 +25,5 @@ export const antigravityProvider: RegistryEntry = {
   },
   models: [...ANTIGRAVITY_PUBLIC_MODELS],
   passthroughModels: true,
+  liveCatalogAuthoritative: false,
 };
diff --git a/open-sse/executors/antigravity.ts b/open-sse/executors/antigravity.ts
index dda321c266..4cd1031cec 100644
--- a/open-sse/executors/antigravity.ts
+++ b/open-sse/executors/antigravity.ts
@@ -521,6 +521,17 @@ export class AntigravityExecutor extends BaseExecutor {
     super("antigravity", PROVIDERS.antigravity);
   }
 
+  override shouldRetry(status: number, urlIndex: number): boolean {
+    return (
+      (status === HTTP_STATUS.RATE_LIMITED ||
+        status === HTTP_STATUS.NOT_FOUND ||
+        status === HTTP_STATUS.BAD_GATEWAY ||
+        status === HTTP_STATUS.SERVICE_UNAVAILABLE ||
+        status === HTTP_STATUS.GATEWAY_TIMEOUT) &&
+      urlIndex + 1 < this.getFallbackCount()
+    );
+  }
+
   buildUrl(model: string, _stream: boolean, urlIndex = 0): string {
     void model;
     const baseUrls = this.getBaseUrls();
diff --git a/src/shared/constants/cliTools.ts b/src/shared/constants/cliTools.ts
index acdba14050..86907635d2 100644
--- a/src/shared/constants/cliTools.ts
+++ b/src/shared/constants/cliTools.ts
@@ -239,6 +239,7 @@ export const CLI_TOOLS: Record<string, CliCatalogEntry> = {
     acpSpawnable: false,
     baseUrlSupport: "none",
     modelAliases: [
+      "gemini-3.7-flash",
       "gemini-3.6-flash-high",
       "gemini-3.6-flash-medium",
       "gemini-3.6-flash-low",
@@ -252,6 +253,7 @@ export const CLI_TOOLS: Record<string, CliCatalogEntry> = {
       "gpt-oss-120b-medium",
     ],
     defaultModels: [
+      createCliModel("gemini-3.7-flash", "Gemini 3.7 Flash"),
       createCliModel("gemini-3.6-flash-high", "Gemini 3.6 Flash High"),
       createCliModel("gemini-3.6-flash-medium", "Gemini 3.6 Flash Medium"),
       createCliModel("gemini-3.6-flash-low", "Gemini 3.6 Flash Low"),
diff --git a/src/shared/constants/modelSpecs.ts b/src/shared/constants/modelSpecs.ts
index 8afe74d3f3..b2ecabbc6c 100644
--- a/src/shared/constants/modelSpecs.ts
+++ b/src/shared/constants/modelSpecs.ts
@@ -174,6 +174,18 @@ export const MODEL_SPECS: Record<string, ModelSpec> = {
     thinkingBudgetCap: 0,
   },
 
+  // ── Gemini 3.7 Flash (Antigravity) — collapsed live id ──────────
+  // Upstream (fetchAvailableModels on daily-cloudcode-pa) also serves this model as a
+  // single `gemini-3.7-flash-tiered` id via the `gemini-3.7-flash` alias in
+  // antigravityModelAliases.ts. Registered independently of the suffixed tier ids below
+  // (#3696 uniqueness invariant: each public id resolves to a distinct upstream id).
+  "gemini-3.7-flash": {
+    ...GEMINI_35_FLASH_MODEL_SPEC,
+    defaultThinkingBudget: 8192,
+    thinkingBudgetCap: 65536,
+    supportsThinking: true,
+  },
+
   // ── Gemini 3.7 / 3.6 Flash (Antigravity live tiers) ─────────────
   // The model id itself selects the upstream 10k/4k/1k reasoning tier. Antigravity
   // still rejects client-supplied thinking parameters, so keep the explicit-parameter
diff --git a/src/shared/constants/pricing/oauth-subscriptions.ts b/src/shared/constants/pricing/oauth-subscriptions.ts
index 7c4a8406c4..b03db8be0c 100644
--- a/src/shared/constants/pricing/oauth-subscriptions.ts
+++ b/src/shared/constants/pricing/oauth-subscriptions.ts
@@ -319,6 +319,13 @@ export const DEFAULT_PRICING_OAUTH = {
     // downstream cost and quota calculations silently fall back to $0.
     // Pricing: $1.50 input / $7.50 output / $0.15 cached per MTok. Thinking tokens
     // billed at output rate.
+    "gemini-3.7-flash": {
+      input: 1.5,
+      output: 7.5,
+      cached: 0.15,
+      reasoning: 7.5,
+      cache_creation: 1.5,
+    },
     "gemini-3.6-flash-low": {
       input: 1.5,
       output: 7.5,
diff --git a/tests/unit/antigravity-model-aliases.test.ts b/tests/unit/antigravity-model-aliases.test.ts
index f1e5cda7f2..ff6c5b550d 100644
--- a/tests/unit/antigravity-model-aliases.test.ts
+++ b/tests/unit/antigravity-model-aliases.test.ts
@@ -18,6 +18,7 @@ function getPublicModel(id: string) {
 }
 
 const EXPECTED_FLASH_TIERS = [
+  ["gemini-3.7-flash", "Gemini 3.7 Flash"],
   ["gemini-3.7-flash-high", "Gemini 3.7 Flash (High)"],
   ["gemini-3.7-flash-medium", "Gemini 3.7 Flash (Medium)"],
   ["gemini-3.6-flash-low", "Gemini 3.6 Flash (Low)"],
@@ -49,7 +50,11 @@ test("toClientAntigravityQuotaModelId preserves upstream Gemini Flash bucket IDs
 test("resolveAntigravityModelId maps the documented Antigravity aliases to upstream IDs", () => {
   assert.equal(resolveAntigravityModelId("gemini-3-pro-image-preview"), "gemini-3-pro-image");
   for (const [modelId] of EXPECTED_FLASH_TIERS) {
-    assert.equal(resolveAntigravityModelId(modelId), modelId);
+    // Only the collapsed gemini-3.7-flash id is aliased to the live upstream
+    // gemini-3.7-flash-tiered id; the suffixed gemini-3.7-flash-high/medium tier ids
+    // (like the 3.6/3.5 tiers) have no alias entry and pass through verbatim.
+    const expected = modelId === "gemini-3.7-flash" ? "gemini-3.7-flash-tiered" : modelId;
+    assert.equal(resolveAntigravityModelId(modelId), expected);
   }
   assert.equal(resolveAntigravityModelId("gemini-claude-sonnet-4-5"), "claude-sonnet-4-6");
   assert.equal(resolveAntigravityModelId("gemini-claude-sonnet-4-5-thinking"), "claude-sonnet-4-6");
@@ -193,7 +198,7 @@ test("AntigravityExecutor.transformRequest preserves Gemini Flash upstream IDs",
     );
 
     if (result instanceof Response) throw new Error("Unexpected Response from transformRequest");
-    assert.equal(result.model, modelId);
+    assert.equal(result.model, resolveAntigravityModelId(modelId));
     assert.deepEqual(result.request.contents, [{ role: "user", parts: [{ text: "Hello" }] }]);
   }
 });