diff --git a/frontend/src/components/ProviderSegment.tsx b/frontend/src/components/ProviderSegment.tsx
index 32228c0c..14171895 100644
--- a/frontend/src/components/ProviderSegment.tsx
+++ b/frontend/src/components/ProviderSegment.tsx
@@ -2,7 +2,7 @@ import { Plus } from "lucide-react";
 
 import { useI18n } from "../i18n";
 import { byProviderCreatedAt } from "../state/ranking";
-import type { ProviderId, StatusResponse } from "../types/api";
+import type { ProtocolId, ProviderId, StatusResponse } from "../types/api";
 import { SelectField } from "./SelectField";
 
 export function ProviderSegment({
@@ -10,11 +10,13 @@ export function ProviderSegment({
   providers,
   onAdd,
   onChange,
+  protocol,
 }: {
   value: ProviderId;
   providers: StatusResponse["providers"];
   onAdd: () => void;
   onChange: (value: ProviderId) => void;
+  protocol?: ProtocolId | "";
 }) {
   const { t } = useI18n();
   return (
@@ -28,7 +30,11 @@ export function ProviderSegment({
           label={t("模型服务")}
           value={value}
           onChange={onChange}
-          options={byProviderCreatedAt(providers).map(([id, provider]) => ({ value: id, label: provider.name }))}
+          options={byProviderCreatedAt(providers).map(([id, provider]) => ({
+            value: id,
+            label: provider.name,
+            disabled: Boolean(protocol) && (protocol === "anthropic" ? !provider.anthropic_base_url : !provider.base_url),
+          }))}
         />
         <button className="provider-add-button" type="button" onClick={onAdd} aria-label={t("新增 Provider")} title={t("新增 Provider")}>
           <Plus size={17} />
diff --git a/frontend/src/components/SelectField.tsx b/frontend/src/components/SelectField.tsx
index ce54a21b..dbae470d 100644
--- a/frontend/src/components/SelectField.tsx
+++ b/frontend/src/components/SelectField.tsx
@@ -4,6 +4,7 @@ import { useEffect, useId, useLayoutEffect, useRef, useState } from "react";
 export interface SelectOption {
   value: string;
   label: string;
+  disabled?: boolean;
 }
 
 interface SelectFieldProps {
@@ -62,7 +63,7 @@ export function SelectField({ value, options, onChange, label, id, className = "
 
   const commit = (index: number) => {
     const option = options[index];
-    if (option) onChange(option.value);
+    if (option && !option.disabled) onChange(option.value);
     close(true);
   };
 
@@ -202,7 +203,8 @@ export function SelectField({ value, options, onChange, label, id, className = "
               id={`${listId}-${index}`}
               role="option"
               aria-selected={option.value === value}
-              className={`select-field-option${index === activeIndex ? " is-active" : ""}`}
+              className={`select-field-option${index === activeIndex ? " is-active" : ""}${option.disabled ? " is-disabled" : ""}`}
+              aria-disabled={option.disabled || undefined}
               // Mouse move rather than hover in CSS, so the keyboard's active
               // option and the pointer's cannot disagree.
               onMouseMove={() => setActiveIndex(index)}
diff --git a/frontend/src/i18n.tsx b/frontend/src/i18n.tsx
index 9da2bafb..dbe58089 100644
--- a/frontend/src/i18n.tsx
+++ b/frontend/src/i18n.tsx
@@ -286,7 +286,7 @@ const english = {
   "官网（可选）": "Website (optional)",
   "OpenAI 兼容 Base URL": "OpenAI-compatible base URL",
   "API 地址：": "API URL: ",
-  "Anthropic 兼容 Base URL（可选）": "Anthropic-compatible base URL (optional)",
+  "Anthropic 兼容 Base URL": "Anthropic-compatible base URL",
   "OpenAI 兼容": "OpenAI-compatible",
   "Anthropic 兼容": "Anthropic-compatible",
   "删除 {name}": "Delete {name}",
diff --git a/frontend/src/pages/AgentProfilePage.tsx b/frontend/src/pages/AgentProfilePage.tsx
index 2bc91241..059b1402 100644
--- a/frontend/src/pages/AgentProfilePage.tsx
+++ b/frontend/src/pages/AgentProfilePage.tsx
@@ -8,8 +8,8 @@ import { ProviderSegment } from "../components/ProviderSegment";
 import { useI18n } from "../i18n";
 import { desktopApps, desktopProfileUsable, desktopProfiles, desktopProtocol, profileAgentIdForDesktop } from "../state/desktopSetup";
 import { useWizard } from "../state/WizardContext";
-import { byProfileCreatedAt } from "../state/ranking";
-import type { ProfileSummary, ProviderId } from "../types/api";
+import { byProfileCreatedAt, byProviderCreatedAt } from "../state/ranking";
+import type { ProfileSummary, ProviderId, ProtocolId } from "../types/api";
 
 interface ProfileDraft {
   id: string;
@@ -42,6 +42,7 @@ export function AgentProfilePage() {
   const catalog = status?.catalog.find((item) => item.id === owner);
   const targetName = app?.name || catalog?.name || agentId;
   const currentAgent = status?.agents[owner];
+  const protocol = (app ? desktopProtocol(app) : catalog?.protocol || "") as ProtocolId | "";
   const [selectedId, setSelectedId] = useState("");
   const [draft, setDraft] = useState<ProfileDraft | null>(null);
   const [busy, setBusy] = useState(false);
@@ -85,7 +86,7 @@ export function AgentProfilePage() {
   const canApply = Boolean(selected && desktopProfileUsable(status, selected));
 
   const openCreate = () => {
-    const provider = Object.keys(status.providers)[0] || "ppio";
+    const provider = byProviderCreatedAt(status.providers).find(([, meta]) => protocol === "anthropic" ? meta.anthropic_base_url : meta.base_url)?.[0] || "ppio";
     const current = selected || profiles[0];
     const baseID = `${owner || "agent"}-${provider}`.toLowerCase().replace(/[^a-z0-9_-]/g, "-");
     const ids = new Set(status.profiles.map((profile) => profile.id));
@@ -205,6 +206,7 @@ export function AgentProfilePage() {
                 providers={status.providers}
                 onAdd={() => navigate(`/providers/new?returnTo=${encodeURIComponent(`/agents/${agentId}`)}`)}
                 onChange={(provider) => setDraft({ ...draft, provider })}
+                protocol={protocol}
               />
             </div>
             <div className="field-stack profile-editor-wide">
diff --git a/frontend/src/pages/ProfilesPage.tsx b/frontend/src/pages/ProfilesPage.tsx
index 43e00d68..ba89e6ea 100644
--- a/frontend/src/pages/ProfilesPage.tsx
+++ b/frontend/src/pages/ProfilesPage.tsx
@@ -81,6 +81,11 @@ export function ProfilesPage() {
     });
   };
 
+  const providerForProtocol = (protocol: string, current: ProviderId) => {
+    if (!protocol || (status.providers[current] && (protocol === "anthropic" ? status.providers[current].anthropic_base_url : status.providers[current].base_url))) return current;
+    return byProviderCreatedAt(status.providers).find(([, provider]) => protocol === "anthropic" ? provider.anthropic_base_url : provider.base_url)?.[0] || current;
+  };
+
   const save = async (event: FormEvent) => {
     event.preventDefault();
     if (!editor || !canSave) return;
@@ -213,7 +218,7 @@ export function ProfilesPage() {
                   id="profile-protocol"
                   label={t("API 类型")}
                   value={editor.protocol}
-                  onChange={(protocol) => setEditor({ ...editor, protocol })}
+                  onChange={(protocol) => setEditor({ ...editor, protocol, provider: providerForProtocol(protocol, editor.provider) })}
                   options={[
                     { value: "", label: t("请选择 API 类型") },
                     ...(Object.keys(PROTOCOL_LABELS) as ProtocolId[]).map((protocol) => ({ value: protocol, label: PROTOCOL_LABELS[protocol] })),
@@ -227,6 +232,7 @@ export function ProfilesPage() {
                 providers={status.providers}
                 onAdd={() => navigate(`/providers/new?returnTo=${encodeURIComponent("/profiles")}`)}
                 onChange={(provider) => setEditor({ ...editor, provider })}
+                protocol={editor.protocol as ProtocolId}
               />
             </div>
             <div className="field-stack profile-editor-wide">
diff --git a/frontend/src/pages/ProviderKeyPage.tsx b/frontend/src/pages/ProviderKeyPage.tsx
index c6d46d6c..fcfe6953 100644
--- a/frontend/src/pages/ProviderKeyPage.tsx
+++ b/frontend/src/pages/ProviderKeyPage.tsx
@@ -97,6 +97,7 @@ export function ProviderKeyPage() {
         providers={state.status?.providers ?? {}}
         onAdd={() => navigate(`/providers/new?returnTo=${encodeURIComponent("/setup/provider")}`)}
         onChange={changeProvider}
+        protocol={protocols.length === 1 ? protocols[0] : ""}
       />
 
       <div className="provider-form">
diff --git a/frontend/src/pages/ProvidersPage.tsx b/frontend/src/pages/ProvidersPage.tsx
index 42bb2661..f8b6a601 100644
--- a/frontend/src/pages/ProvidersPage.tsx
+++ b/frontend/src/pages/ProvidersPage.tsx
@@ -147,11 +147,11 @@ export function ProvidersPage({ create = false }: { create?: boolean }) {
             </div>
             <div className="field-stack provider-editor-wide">
               <label htmlFor="provider-base-url">{t("OpenAI 兼容 Base URL")}</label>
-              <input id="provider-base-url" type="url" value={editor.base_url} onChange={(event) => setEditor({ ...editor, base_url: event.target.value })} placeholder="https://api.example.com/openai" required />
+                <input id="provider-base-url" type="url" value={editor.base_url} onChange={(event) => setEditor({ ...editor, base_url: event.target.value })} placeholder="https://api.example.com/openai/v1" />
             </div>
             <div className="field-stack provider-editor-wide">
-              <label htmlFor="provider-anthropic-url">{t("Anthropic 兼容 Base URL（可选）")}</label>
-              <input id="provider-anthropic-url" type="url" value={editor.anthropic_base_url} onChange={(event) => setEditor({ ...editor, anthropic_base_url: event.target.value })} placeholder="https://api.example.com/anthropic" />
+              <label htmlFor="provider-anthropic-url">{t("Anthropic 兼容 Base URL")}</label>
+              <input id="provider-anthropic-url" type="url" value={editor.anthropic_base_url} onChange={(event) => setEditor({ ...editor, anthropic_base_url: event.target.value })} placeholder="https://api.example.com/anthropic/v1" />
             </div>
             <div className="field-stack provider-editor-wide">
               <label htmlFor="provider-home">{t("官网（可选）")}</label>
diff --git a/frontend/src/state/wizardReducer.ts b/frontend/src/state/wizardReducer.ts
index 834e8afd..f91e0589 100644
--- a/frontend/src/state/wizardReducer.ts
+++ b/frontend/src/state/wizardReducer.ts
@@ -82,8 +82,8 @@ export const initialWizardState: WizardState = {
   activationNext: "",
 };
 
-function latestProvider(status: StatusResponse | null): ProviderId {
-  return byProviderCreatedAt(status?.providers ?? {})[0]?.[0] || "ppio";
+function latestProvider(status: StatusResponse | null, protocol?: string): ProviderId {
+  return byProviderCreatedAt(status?.providers ?? {}).find(([, provider]) => !protocol || (protocol === "anthropic" ? provider.anthropic_base_url : provider.base_url))?.[0] || "ppio";
 }
 
 export type WizardAction =
@@ -182,6 +182,7 @@ export function wizardReducer(state: WizardState, action: WizardAction): WizardS
         return {
           ...state,
           selectedAgentIds: [action.agentId],
+          provider: latestProvider(state.status, state.status?.catalog.find((item) => item.id === action.agentId)?.protocol || undefined),
           desktopProfileId: state.selectedAgentIds[0] === action.agentId ? state.desktopProfileId : "",
           // Profile IDs and labels are derived from the selected Agent and
           // Provider. Do not carry a prior run's profile into a new pairing.
diff --git a/frontend/src/styles/base.css b/frontend/src/styles/base.css
index 3a447494..230183a0 100644
--- a/frontend/src/styles/base.css
+++ b/frontend/src/styles/base.css
@@ -267,6 +267,12 @@ button:active:not(:disabled) {
   background: var(--surface-subtle);
 }
 
+.select-field-option.is-disabled {
+  color: var(--text-tertiary);
+  opacity: 0.65;
+  cursor: not-allowed;
+}
+
 .select-field-check {
   flex: 0 0 auto;
   color: var(--blue);
diff --git a/internal/app/status.go b/internal/app/status.go
index 10f92a7d..fb1e9aca 100644
--- a/internal/app/status.go
+++ b/internal/app/status.go
@@ -475,7 +475,7 @@ func (u *UseCases) SaveProfile(ctx context.Context, options SaveProfileOptions)
 		ID:       options.ID,
 		Label:    options.Label,
 		Provider: options.Provider,
-		BaseURL:  target.BaseURL,
+		BaseURL:  target.BaseFor(options.Protocol),
 		// Keep explicit keys accepted by callers, but do not copy a
 		// Provider-resolved key into every Profile secret file.
 		APIKey:               providedKey,
diff --git a/internal/app/status_test.go b/internal/app/status_test.go
index c1921862..390e495b 100644
--- a/internal/app/status_test.go
+++ b/internal/app/status_test.go
@@ -10,6 +10,7 @@ import (
 	"testing"
 
 	"github.com/MaimoryLab/OneAgent/internal/platform"
+	"github.com/MaimoryLab/OneAgent/internal/provider"
 )
 
 func TestStatusUsesInjectedHomeAndCommandLookup(t *testing.T) {
@@ -198,6 +199,16 @@ func TestSaveProfileCanSwitchAKeylessProfileProvider(t *testing.T) {
 	}
 }
 
+func TestSaveProfileUsesProtocolEndpoint(t *testing.T) {
+	core := NewUseCases(StatusOptions{Home: t.TempDir(), Platform: platform.For("linux", "amd64"), Lookup: func(string) (string, bool) { return "", false }})
+	if _, err := core.SaveProvider(context.Background(), provider.Entry{ID: "anthropic-only", Name: "Anthropic", AnthropicBaseURL: "https://api.example.test/anthropic"}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := core.SaveProfile(context.Background(), SaveProfileOptions{ID: "anthropic", Provider: "anthropic-only", Model: "model", ConfigMode: "provider", Protocol: "anthropic"}); err != nil {
+		t.Fatal(err)
+	}
+}
+
 func TestStatusProjectsAgentBindingsWithoutUnknownFields(t *testing.T) {
 	home := t.TempDir()
 	path := filepath.Join(home, ".oneagent", "agents", "codex.json")
diff --git a/internal/provider/store.go b/internal/provider/store.go
index 2722626a..92fc489a 100644
--- a/internal/provider/store.go
+++ b/internal/provider/store.go
@@ -217,8 +217,13 @@ func validateEntry(entry Entry) error {
 	if entry.Name == "" {
 		return oneerrors.New(oneerrors.InvalidRequest, "Provider name is required")
 	}
-	if _, err := ValidateBaseURL(entry.BaseURL); err != nil {
-		return err
+	if entry.BaseURL == "" && entry.AnthropicBaseURL == "" {
+		return oneerrors.New(oneerrors.InvalidRequest, "At least one API base URL is required")
+	}
+	if entry.BaseURL != "" {
+		if _, err := ValidateBaseURL(entry.BaseURL); err != nil {
+			return err
+		}
 	}
 	if entry.Home != "" {
 		if _, err := ValidateBaseURL(entry.Home); err != nil {
diff --git a/internal/provider/store_test.go b/internal/provider/store_test.go
index 4bc5e179..d30a27a8 100644
--- a/internal/provider/store_test.go
+++ b/internal/provider/store_test.go
@@ -43,3 +43,18 @@ func TestStorePersistsCRUDAndPrivateKey(t *testing.T) {
 		t.Fatal("deleted Provider was still readable")
 	}
 }
+
+func TestStoreAcceptsEitherAPIEndpoint(t *testing.T) {
+	store := NewStore(t.TempDir(), securefs.New(securefs.Options{OS: "linux"}))
+	for _, entry := range []Entry{
+		{ID: "anthropic-only", Name: "Anthropic", AnthropicBaseURL: "https://api.example.test/anthropic"},
+		{ID: "openai-only", Name: "OpenAI", BaseURL: "https://api.example.test/openai"},
+	} {
+		if _, err := store.Save(context.Background(), entry); err != nil {
+			t.Fatalf("save %s: %v", entry.ID, err)
+		}
+	}
+	if _, err := store.Save(context.Background(), Entry{ID: "empty", Name: "Empty"}); err == nil {
+		t.Fatal("empty Provider unexpectedly saved")
+	}
+}