diff --git a/packages/opencode/src/provider/transform.ts b/packages/opencode/src/provider/transform.ts
index 688e7dc8c985..ea55bb2ce65b 100644
--- a/packages/opencode/src/provider/transform.ts
+++ b/packages/opencode/src/provider/transform.ts
@@ -697,6 +697,10 @@ export function variants(model: Provider.Model): Record<string, Record<string, a
               {
                 thinking: {
                   type: "adaptive",
+                  // Opus 4.7+ flips the API default for `display` to "omitted", which
+                  // returns empty thinking blocks. Force "summarized" so summaries
+                  // survive (4.6/Sonnet 4.6 already default to "summarized").
+                  ...(adaptiveOpus ? { display: "summarized" } : {}),
                 },
                 effort,
               },
diff --git a/packages/opencode/test/provider/transform.test.ts b/packages/opencode/test/provider/transform.test.ts
index ae99d3f10eef..dad1987de8fe 100644
--- a/packages/opencode/test/provider/transform.test.ts
+++ b/packages/opencode/test/provider/transform.test.ts
@@ -2681,12 +2681,14 @@ describe("ProviderTransform.variants", () => {
       expect(result.xhigh).toEqual({
         thinking: {
           type: "adaptive",
+          display: "summarized",
         },
         effort: "xhigh",
       })
       expect(result.max).toEqual({
         thinking: {
           type: "adaptive",
+          display: "summarized",
         },
         effort: "max",
       })
@@ -2706,6 +2708,47 @@ describe("ProviderTransform.variants", () => {
       expect(Object.keys(result)).toEqual(["low", "medium", "high", "xhigh", "max"])
     })
 
+    test("anthropic opus 4.8 forces display summarized for adaptive reasoning", () => {
+      const model = createMockModel({
+        id: "anthropic/claude-opus-4-8",
+        providerID: "gateway",
+        api: {
+          id: "anthropic/claude-opus-4-8",
+          url: "https://gateway.ai",
+          npm: "@ai-sdk/gateway",
+        },
+      })
+      const result = ProviderTransform.variants(model)
+      expect(Object.keys(result)).toEqual(["low", "medium", "high", "xhigh", "max"])
+      expect(result.high).toEqual({
+        thinking: {
+          type: "adaptive",
+          display: "summarized",
+        },
+        effort: "high",
+      })
+    })
+
+    test("anthropic opus 4.6 omits display so it keeps the summarized default", () => {
+      const model = createMockModel({
+        id: "anthropic/claude-opus-4-6",
+        providerID: "gateway",
+        api: {
+          id: "anthropic/claude-opus-4-6",
+          url: "https://gateway.ai",
+          npm: "@ai-sdk/gateway",
+        },
+      })
+      const result = ProviderTransform.variants(model)
+      expect(Object.keys(result)).toEqual(["low", "medium", "high", "max"])
+      expect(result.high).toEqual({
+        thinking: {
+          type: "adaptive",
+        },
+        effort: "high",
+      })
+    })
+
     test("anthropic models return anthropic thinking options", () => {
       const model = createMockModel({
         id: "anthropic/claude-sonnet-4",