diff --git a/changelog.d/fixes/8610-opencode-go-effort-catalog.md b/changelog.d/fixes/8610-opencode-go-effort-catalog.md
new file mode 100644
index 0000000000..4228bdc40c
--- /dev/null
+++ b/changelog.d/fixes/8610-opencode-go-effort-catalog.md
@@ -0,0 +1 @@
+- **fix(providers):** keep registered OpenCode Go effort aliases in the Playground catalog when synced base models are present, and preserve Hunyuan3's 256K context metadata for combo routing ([#8610](https://github.com/diegosouzapw/OmniRoute/pull/8610)).
diff --git a/open-sse/config/providers/registry/opencode/go/index.ts b/open-sse/config/providers/registry/opencode/go/index.ts
index 4ead5d8823..9ff9deda62 100644
--- a/open-sse/config/providers/registry/opencode/go/index.ts
+++ b/open-sse/config/providers/registry/opencode/go/index.ts
@@ -106,10 +106,25 @@ export const opencode_goProvider: RegistryEntry = {
     },
     { id: "qwen3.5-plus", name: "Qwen3.5 Plus", targetFormat: "claude", supportsVision: false },
     // #8353: hy3 is the Go-tier base id (distinct from hy3-preview / hy3-free).
-    { id: "hy3", name: "Hunyuan3", supportsReasoning: true },
-    { id: "hy3-none", name: "Hunyuan3 (none effort)", supportsReasoning: true },
-    { id: "hy3-low", name: "Hunyuan3 (low effort)", supportsReasoning: true },
-    { id: "hy3-high", name: "Hunyuan3 (high effort)", supportsReasoning: true },
+    { id: "hy3", name: "Hunyuan3", contextLength: 256000, supportsReasoning: true },
+    {
+      id: "hy3-none",
+      name: "Hunyuan3 (none effort)",
+      contextLength: 256000,
+      supportsReasoning: true,
+    },
+    {
+      id: "hy3-low",
+      name: "Hunyuan3 (low effort)",
+      contextLength: 256000,
+      supportsReasoning: true,
+    },
+    {
+      id: "hy3-high",
+      name: "Hunyuan3 (high effort)",
+      contextLength: 256000,
+      supportsReasoning: true,
+    },
     { id: "hy3-preview", name: "Hunyuan3 Preview" },
     // #8353: Grok 4.5 + effort tiers from the OpenCode Go registry.
     { id: "grok-4.5", name: "Grok 4.5", supportsReasoning: true },
diff --git a/src/app/api/v1/models/catalog.ts b/src/app/api/v1/models/catalog.ts
index 5339e10801..34ccbdfbaf 100644
--- a/src/app/api/v1/models/catalog.ts
+++ b/src/app/api/v1/models/catalog.ts
@@ -662,6 +662,18 @@ async function buildUnifiedModelsResponseCore(
         return Array.isArray(models) && models.length > 0;
       })
     );
+    const isRegisteredEffortVariant = (
+      providerModels: Array<{ id: string }>,
+      modelId: string
+    ): boolean => {
+      for (const suffix of ["none", "low", "medium", "high", "max", "xhigh"]) {
+        const suffixWithSeparator = `-${suffix}`;
+        if (!modelId.endsWith(suffixWithSeparator)) continue;
+        const baseModelId = modelId.slice(0, -suffixWithSeparator.length);
+        return providerModels.some((candidate) => candidate.id === baseModelId);
+      }
+      return false;
+    };
 
     // Add provider models (chat)
     for (const [alias, providerModels] of Object.entries(PROVIDER_MODELS)) {
@@ -680,9 +692,14 @@ async function buildUnifiedModelsResponseCore(
         continue;
       }
 
-      if (providersWithSyncedModels.has(canonicalProviderId)) continue;
-
       for (const model of providerModels) {
+        // Synced models replace static base entries, but they do not carry aliases
+        // registered for provider-specific reasoning variants.
+        if (
+          providersWithSyncedModels.has(canonicalProviderId) &&
+          !isRegisteredEffortVariant(providerModels, model.id)
+        )
+          continue;
         if (!providerSupportsModel(canonicalProviderId, model.id)) continue;
         const aliasId = `${alias}/${model.id}`;
         if (getModelIsHidden(canonicalProviderId, model.id)) continue;
diff --git a/tests/unit/models-catalog-route.test.ts b/tests/unit/models-catalog-route.test.ts
index ed76e9a59e..2db47dbf9c 100644
--- a/tests/unit/models-catalog-route.test.ts
+++ b/tests/unit/models-catalog-route.test.ts
@@ -851,6 +851,34 @@ test("v1 models catalog includes synced non-Gemini provider models from discover
   assert.equal(syncedModel.context_length, 262144);
 });
 
+test("v1 models catalog retains registered effort aliases beside synced OpenCode Go bases", async () => {
+  const connection = await seedConnection("opencode-go", {
+    name: "opencode-go-effort-aliases",
+    apiKey: "go-key",
+  });
+
+  await modelsDb.replaceSyncedAvailableModelsForConnection("opencode-go", connection.id, [
+    {
+      id: "hy3",
+      name: "Hunyuan3",
+      source: "imported",
+      supportedEndpoints: ["chat"],
+    },
+  ]);
+
+  const response = await v1ModelsCatalog.getUnifiedModelsResponse(
+    new Request("http://localhost/api/v1/models")
+  );
+  const body = (await response.json()) as { data: Array<{ id: string }> };
+  const ids = body.data.map((item: { id: string }) => item.id);
+
+  assert.equal(response.status, 200);
+  assert.ok(ids.includes("opencode-go/hy3"));
+  assert.ok(ids.includes("opencode-go/hy3-none"));
+  assert.ok(ids.includes("opencode-go/hy3-low"));
+  assert.ok(ids.includes("opencode-go/hy3-high"));
+});
+
 test("v1 models catalog advertises GLM-5.2 provider aliases with hosted context limits", async () => {
   const hfConnection = await seedConnection("huggingface", {
     name: "huggingface-glm52",
diff --git a/tests/unit/opencode-go-catalog-alignment.test.ts b/tests/unit/opencode-go-catalog-alignment.test.ts
index 6b9bd3b68b..ba7dba12c6 100644
--- a/tests/unit/opencode-go-catalog-alignment.test.ts
+++ b/tests/unit/opencode-go-catalog-alignment.test.ts
@@ -13,6 +13,7 @@ import assert from "node:assert/strict";
 
 const { opencode_goProvider } =
   await import("../../open-sse/config/providers/registry/opencode/go/index.ts");
+const { getResolvedModelCapabilities } = await import("../../src/lib/modelCapabilities.ts");
 
 function modelIds(): string[] {
   return (opencode_goProvider.models ?? []).map((m) => m.id);
@@ -51,3 +52,13 @@ test("opencode-go preserves the pre-existing minimax-m3 and qwen routing via tar
   assert.equal(byId.get("minimax-m3")?.targetFormat, "claude");
   assert.equal(byId.get("qwen3.7-max")?.targetFormat, "claude");
 });
+
+test("opencode-go hy3 variants expose their context window to combo compatibility filtering", () => {
+  for (const modelId of ["hy3", "hy3-none", "hy3-low", "hy3-high"]) {
+    assert.equal(
+      getResolvedModelCapabilities(`opencode-go/${modelId}`).contextWindow,
+      256000,
+      `${modelId} should resolve a 256K context window`
+    );
+  }
+});