fix(provider): adjust OpenAI-compatible request fields

pkg/providers/openai_compat/provider.go

@@ -164,6 +164,10 @@ func (p *Provider) Chat(
 		}
 	}
 
+	if strings.Contains(p.apiBase, "api.minimaxi.com") {
+		requestBody["reasoning_split"] = true
+	}
+
 	jsonData, err := json.Marshal(requestBody)
 	if err != nil {
 		return nil, fmt.Errorf("failed to marshal request: %w", err)

pkg/providers/openai_compat/provider_test.go

@@ -60,6 +60,71 @@ func TestProviderChat_UsesMaxCompletionTokensForGLM(t *testing.T) {
 	}
 }
 
+func TestProviderChat_SkipsPromptCacheKeyForNvidia(t *testing.T) {
+	var requestBody map[string]any
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if err := json.NewDecoder(r.Body).Decode(&requestBody); err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(`{"choices":[{"message":{"content":"ok"},"finish_reason":"stop"}]}`))
+	}))
+	defer server.Close()
+
+	p := NewProvider("key", server.URL+"/integrate.api.nvidia.com/v1", "")
+	p.apiBase = server.URL + "/integrate.api.nvidia.com/v1"
+
+	_, err := p.Chat(
+		t.Context(),
+		[]Message{{Role: "user", Content: "hi"}},
+		nil,
+		"nvidia/llama-3.1",
+		map[string]any{"prompt_cache_key": "agent-main"},
+	)
+	if err != nil {
+		t.Fatalf("Chat() error = %v", err)
+	}
+	if _, ok := requestBody["prompt_cache_key"]; ok {
+		t.Fatalf("did not expect prompt_cache_key for nvidia endpoint")
+	}
+}
+
+func TestProviderChat_EnablesReasoningSplitForMiniMax(t *testing.T) {
+	var requestBody map[string]any
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if err := json.NewDecoder(r.Body).Decode(&requestBody); err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(`{"choices":[{"message":{"content":"ok","reasoning_details":[{"type":"reasoning","text":"think"}]},"finish_reason":"stop"}]}`))
+	}))
+	defer server.Close()
+
+	p := NewProvider("key", server.URL+"/api.minimaxi.com/v1", "")
+	p.apiBase = server.URL + "/api.minimaxi.com/v1"
+
+	out, err := p.Chat(
+		t.Context(),
+		[]Message{{Role: "user", Content: "hi"}},
+		nil,
+		"minimax/MiniMax-M2.5",
+		nil,
+	)
+	if err != nil {
+		t.Fatalf("Chat() error = %v", err)
+	}
+	if requestBody["reasoning_split"] != true {
+		t.Fatalf("reasoning_split = %v, want true", requestBody["reasoning_split"])
+	}
+	if len(out.ReasoningDetails) != 1 {
+		t.Fatalf("len(ReasoningDetails) = %d, want 1", len(out.ReasoningDetails))
+	}
+}
+
 func TestProviderChat_ParsesToolCalls(t *testing.T) {
 	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		resp := map[string]any{