feat(realtime-canvas): migrate provider to BFL flux.2

app/(admin)/settings/admin-settings-client.tsx

@@ -102,8 +102,8 @@ import {
 import { fetchUploadWithRetry } from "@/lib/client/upload-with-retry";
 
 const fetcher = (url: string) => fetch(url).then((res) => res.json());
-const DEFAULT_RUNWARE_REALTIME_MODEL = "runware:101@1";
-const DEFAULT_RUNWARE_STYLIZE_MODEL = "runware:106@1";
+const DEFAULT_BFL_REALTIME_MODEL = "flux-2-klein-4b";
+const DEFAULT_BFL_BASE_URL = "https://api.bfl.ai";
 
 function createEmptyCanvasSkillTag(): CanvasSkillTag {
   return {
@@ -810,11 +810,9 @@ export function AdminSettingsClient() {
   // 实时画布API配置状态
   const [realtimeCanvasConfig, setRealtimeCanvasConfig] = useState({
     enabled: true,
-    falApiKey: "",
-    runwareModel: DEFAULT_RUNWARE_REALTIME_MODEL,
-    runwareStylizeModel: DEFAULT_RUNWARE_STYLIZE_MODEL,
-    runwareControlModel: "runware:25@1",
-    runwareControlPreprocessor: "canny" as "canny" | "lineart" | "depth",
+    bflApiKey: "",
+    bflBaseUrl: DEFAULT_BFL_BASE_URL,
+    bflModel: DEFAULT_BFL_REALTIME_MODEL,
     renderMode: "balanced" as "strict-structure" | "balanced" | "stylize",
     throttleInterval: 100,
     maxBuffering: 2,
@@ -970,12 +968,12 @@ export function AdminSettingsClient() {
     if (realtimeCanvasConfigData?.setting?.value) {
       const config = realtimeCanvasConfigData.setting.value as {
         enabled?: boolean;
+        bflApiKey?: string;
+        bflBaseUrl?: string;
+        bflModel?: string;
         runwareApiKey?: string;
         falApiKey?: string;
         runwareModel?: string;
-        runwareStylizeModel?: string;
-        runwareControlModel?: string;
-        runwareControlPreprocessor?: "canny" | "lineart" | "depth";
         renderMode?: "strict-structure" | "balanced" | "stylize";
         throttleInterval?: number;
         maxBuffering?: number;
@@ -990,15 +988,9 @@ export function AdminSettingsClient() {
       };
       setRealtimeCanvasConfig({
         enabled: config.enabled ?? true,
-        falApiKey: config.runwareApiKey || config.falApiKey || "",
-        runwareModel: config.runwareModel || DEFAULT_RUNWARE_REALTIME_MODEL,
-        runwareStylizeModel: config.runwareStylizeModel || DEFAULT_RUNWARE_STYLIZE_MODEL,
-        runwareControlModel: config.runwareControlModel || "runware:25@1",
-        runwareControlPreprocessor:
-          config.runwareControlPreprocessor === "lineart" ||
-          config.runwareControlPreprocessor === "depth"
-            ? config.runwareControlPreprocessor
-            : "canny",
+        bflApiKey: config.bflApiKey || config.runwareApiKey || config.falApiKey || "",
+        bflBaseUrl: config.bflBaseUrl || DEFAULT_BFL_BASE_URL,
+        bflModel: config.bflModel || config.runwareModel || DEFAULT_BFL_REALTIME_MODEL,
         renderMode:
           config.renderMode === "strict-structure" || config.renderMode === "stylize"
             ? config.renderMode
@@ -2031,36 +2023,29 @@ export function AdminSettingsClient() {
   // --- 实时画布API配置逻辑 ---
   const handleSaveRealtimeCanvasConfig = async () => {
     try {
-      const runwareApiKey = realtimeCanvasConfig.falApiKey.trim();
-      const runwareModel =
-        realtimeCanvasConfig.runwareModel.trim() || DEFAULT_RUNWARE_REALTIME_MODEL;
-      const runwareStylizeModel =
-        realtimeCanvasConfig.runwareStylizeModel.trim() || DEFAULT_RUNWARE_STYLIZE_MODEL;
-      const runwareControlModel =
-        realtimeCanvasConfig.runwareControlModel.trim() || "runware:25@1";
+      const bflApiKey = realtimeCanvasConfig.bflApiKey.trim();
+      const bflBaseUrl = realtimeCanvasConfig.bflBaseUrl.trim() || DEFAULT_BFL_BASE_URL;
+      const bflModel = realtimeCanvasConfig.bflModel.trim() || DEFAULT_BFL_REALTIME_MODEL;
 
-      if (realtimeCanvasConfig.enabled && !runwareApiKey) {
-        toast.error("启用实时画布功能需要配置 Runware API Key");
+      if (realtimeCanvasConfig.enabled && !bflApiKey) {
+        toast.error("启用实时画布功能需要配置 BFL API Key");
         return;
       }
 
       if (realtimeCanvasConfig.enabled) {
-        for (const modelId of [runwareModel, runwareStylizeModel].filter(Boolean)) {
-          const probeResponse = await fetch("/api/admin/realtime/model-capability", {
-            method: "POST",
-            headers: { "Content-Type": "application/json" },
-            body: JSON.stringify({
-              apiKey: runwareApiKey,
-              modelId,
-            }),
-          });
-          const probeData = await probeResponse.json().catch(() => null);
-          if (!probeResponse.ok || probeData?.supported === false) {
-            toast.error(
-              probeData?.message || "模型能力探针失败：当前模型不支持 seedImage，已阻止保存"
-            );
-            return;
-          }
+        const probeResponse = await fetch("/api/admin/realtime/model-capability", {
+          method: "POST",
+          headers: { "Content-Type": "application/json" },
+          body: JSON.stringify({
+            apiKey: bflApiKey,
+            modelId: bflModel,
+            baseUrl: bflBaseUrl,
+          }),
+        });
+        const probeData = await probeResponse.json().catch(() => null);
+        if (!probeResponse.ok || probeData?.supported === false) {
+          toast.error(probeData?.message || "模型能力探针失败，已阻止保存");
+          return;
         }
       }
 
@@ -2071,12 +2056,12 @@ export function AdminSettingsClient() {
           key: "realtime_canvas_config",
           value: {
             enabled: realtimeCanvasConfig.enabled,
-            runwareApiKey,
-            falApiKey: runwareApiKey,
-            runwareModel,
-            runwareStylizeModel,
-            runwareControlModel,
-            runwareControlPreprocessor: realtimeCanvasConfig.runwareControlPreprocessor,
+            bflApiKey,
+            bflBaseUrl,
+            bflModel,
+            runwareApiKey: bflApiKey,
+            falApiKey: bflApiKey,
+            runwareModel: bflModel,
             renderMode: realtimeCanvasConfig.renderMode,
             throttleInterval: Math.min(260, Math.max(60, Number(realtimeCanvasConfig.throttleInterval) || 100)),
             maxBuffering: Math.min(6, Math.max(1, Number(realtimeCanvasConfig.maxBuffering) || 2)),
@@ -8359,7 +8344,7 @@ export function AdminSettingsClient() {
                 实时画布配置
               </CardTitle>
               <CardDescription>
-                配置实时画布功能的 Runware 参数、模型与 API Key。保存时会自动探针校验模型是否支持 seedImage。
+                配置实时画布功能的 BFL（FLUX.2）参数、模型与 API Key。保存时会自动探针校验模型可用性。
               </CardDescription>
             </CardHeader>
             <CardContent className="space-y-6 pt-6">
@@ -8384,67 +8369,50 @@ export function AdminSettingsClient() {
               </div>
 
               <div className="space-y-2">
-                <Label htmlFor="realtimeFalApiKey">
-                  Runware API Key <span className="text-destructive">*</span>
+                <Label htmlFor="realtimeBflApiKey">
+                  BFL API Key <span className="text-destructive">*</span>
                 </Label>
                 <Input
-                  id="realtimeFalApiKey"
+                  id="realtimeBflApiKey"
                   type="password"
-                  value={realtimeCanvasConfig.falApiKey}
+                  value={realtimeCanvasConfig.bflApiKey}
                   onChange={(e) =>
-                    setRealtimeCanvasConfig({ ...realtimeCanvasConfig, falApiKey: e.target.value })
+                    setRealtimeCanvasConfig({ ...realtimeCanvasConfig, bflApiKey: e.target.value })
                   }
-                  placeholder="rw_xxxxxxxxxxxxx"
+                  placeholder="bfl_xxxxxxxxxxxxx"
                   disabled={!realtimeCanvasConfig.enabled}
                 />
               </div>
 
               <div className="space-y-2">
-                <Label htmlFor="runwareModel">
-                  Runware 模型 ID <span className="text-destructive">*</span>
+                <Label htmlFor="realtimeBflBaseUrl">BFL API Base URL</Label>
+                <Input
+                  id="realtimeBflBaseUrl"
+                  value={realtimeCanvasConfig.bflBaseUrl}
+                  onChange={(e) =>
+                    setRealtimeCanvasConfig({ ...realtimeCanvasConfig, bflBaseUrl: e.target.value })
+                  }
+                  placeholder={DEFAULT_BFL_BASE_URL}
+                  disabled={!realtimeCanvasConfig.enabled}
+                />
+              </div>
+
+              <div className="space-y-2">
+                <Label htmlFor="realtimeBflModel">
+                  FLUX.2 模型 ID <span className="text-destructive">*</span>
                 </Label>
                 <Input
-                  id="runwareModel"
-                  value={realtimeCanvasConfig.runwareModel}
+                  id="realtimeBflModel"
+                  value={realtimeCanvasConfig.bflModel}
                   onChange={(e) =>
-                    setRealtimeCanvasConfig({ ...realtimeCanvasConfig, runwareModel: e.target.value })
+                    setRealtimeCanvasConfig({ ...realtimeCanvasConfig, bflModel: e.target.value })
                   }
-                  placeholder={DEFAULT_RUNWARE_REALTIME_MODEL}
+                  placeholder={DEFAULT_BFL_REALTIME_MODEL}
                   disabled={!realtimeCanvasConfig.enabled}
                 />
               </div>
 
-              <div className="space-y-2">
-                <Label htmlFor="runwareStylizeModel">写实增强模型 ID</Label>
-                <Input
-                  id="runwareStylizeModel"
-                  value={realtimeCanvasConfig.runwareStylizeModel}
-                  onChange={(e) =>
-                    setRealtimeCanvasConfig({
-                      ...realtimeCanvasConfig,
-                      runwareStylizeModel: e.target.value,
-                    })
-                  }
-                  placeholder={DEFAULT_RUNWARE_STYLIZE_MODEL}
-                  disabled={!realtimeCanvasConfig.enabled}
-                />
-              </div>
-              <div className="space-y-2">
-                <Label htmlFor="runwareControlModel">ControlNet 模型 ID</Label>
-                <Input
-                  id="runwareControlModel"
-                  value={realtimeCanvasConfig.runwareControlModel}
-                  onChange={(e) =>
-                    setRealtimeCanvasConfig({
-                      ...realtimeCanvasConfig,
-                      runwareControlModel: e.target.value,
-                    })
-                  }
-                  placeholder="runware:25@1"
-                  disabled={!realtimeCanvasConfig.enabled}
-                />
-              </div>
-              <div className="grid grid-cols-2 gap-4">
+              <div className="grid grid-cols-1 gap-4">
                 <div className="space-y-2">
                   <Label>实时渲染模式</Label>
                   <Select
@@ -8465,30 +8433,9 @@ export function AdminSettingsClient() {
                     </SelectContent>
                   </Select>
                 </div>
-                <div className="space-y-2">
-                  <Label>ControlNet 预处理</Label>
-                  <Select
-                    value={realtimeCanvasConfig.runwareControlPreprocessor}
-                    onValueChange={(value: "canny" | "lineart" | "depth") =>
-                      setRealtimeCanvasConfig({
-                        ...realtimeCanvasConfig,
-                        runwareControlPreprocessor: value,
-                      })
-                    }
-                  >
-                    <SelectTrigger>
-                      <SelectValue />
-                    </SelectTrigger>
-                    <SelectContent>
-                      <SelectItem value="canny">canny</SelectItem>
-                      <SelectItem value="lineart">lineart</SelectItem>
-                      <SelectItem value="depth">depth</SelectItem>
-                    </SelectContent>
-                  </Select>
-                </div>
               </div>
               <p className="text-xs text-muted-foreground">
-                推荐：主模型 {DEFAULT_RUNWARE_REALTIME_MODEL} + ControlNet {`runware:25@1`}。写实模型 {DEFAULT_RUNWARE_STYLIZE_MODEL} 作为回退链路。
+                推荐：实时草图模型使用 `flux-2-klein-4b`，高质量可切换 `flux-2-pro-preview`。
               </p>
 
               <div className="grid grid-cols-2 gap-4">

app/api/admin/realtime/model-capability/route.ts

@@ -1,11 +1,12 @@
 import { z } from "zod";
 import { requireAdmin } from "@/lib/middleware/admin";
 import { ChatSDKError } from "@/lib/errors";
-import { probeRunwareSeedImageSupport } from "@/lib/realtime/runware-capability";
+import { probeBflModelSupport } from "@/lib/realtime/bfl-capability";
 
 const schema = z.object({
   apiKey: z.string().min(1),
   modelId: z.string().min(1),
+  baseUrl: z.string().optional(),
 });
 
 function mapStatus(code: string) {
@@ -19,9 +20,10 @@ export async function POST(request: Request) {
 
     const body = await request.json();
     const data = schema.parse(body);
-    const result = await probeRunwareSeedImageSupport({
+    const result = await probeBflModelSupport({
       apiKey: data.apiKey,
       modelId: data.modelId,
+      baseUrl: data.baseUrl,
     });
 
     if (!result.supported) {

app/api/admin/settings/route.ts

@@ -6,16 +6,15 @@ import {
   upsertSystemSetting,
 } from "@/lib/db/queries";
 import { ChatSDKError } from "@/lib/errors";
-import { probeRunwareSeedImageSupport } from "@/lib/realtime/runware-capability";
+import { probeBflModelSupport } from "@/lib/realtime/bfl-capability";
 
 const settingSchema = z.object({
   key: z.string(),
   value: z.any(),
 });
 
-const DEFAULT_RUNWARE_MODEL = "runware:101@1";
-const DEFAULT_RUNWARE_STYLIZE_MODEL = "runware:106@1";
-const DEFAULT_RUNWARE_CONTROL_MODEL = "runware:25@1";
+const DEFAULT_BFL_MODEL = "flux-2-klein-4b";
+const DEFAULT_BFL_BASE_URL = "https://api.bfl.ai";
 
 function isObjectLike(value: unknown): value is Record<string, unknown> {
   return Boolean(value) && typeof value === "object" && !Array.isArray(value);
@@ -63,18 +62,11 @@ export async function POST(request: Request) {
       }
 
       const enabled = value.enabled !== false;
-      const runwareApiKey = String(value.runwareApiKey || value.falApiKey || value.apiKey || "").trim();
-      const runwareModel = String(value.runwareModel || DEFAULT_RUNWARE_MODEL).trim() || DEFAULT_RUNWARE_MODEL;
-      const runwareStylizeModel =
-        String(value.runwareStylizeModel || DEFAULT_RUNWARE_STYLIZE_MODEL).trim() ||
-        DEFAULT_RUNWARE_STYLIZE_MODEL;
-      const runwareControlModel =
-        String(value.runwareControlModel || DEFAULT_RUNWARE_CONTROL_MODEL).trim() ||
-        DEFAULT_RUNWARE_CONTROL_MODEL;
-      const runwareControlPreprocessor =
-        value.runwareControlPreprocessor === "lineart" || value.runwareControlPreprocessor === "depth"
-          ? value.runwareControlPreprocessor
-          : "canny";
+      const bflApiKey = String(
+        value.bflApiKey || value.runwareApiKey || value.falApiKey || value.apiKey || ""
+      ).trim();
+      const bflModel = String(value.bflModel || value.runwareModel || DEFAULT_BFL_MODEL).trim() || DEFAULT_BFL_MODEL;
+      const bflBaseUrl = String(value.bflBaseUrl || DEFAULT_BFL_BASE_URL).trim() || DEFAULT_BFL_BASE_URL;
       const renderMode =
         value.renderMode === "strict-structure" ||
         value.renderMode === "stylize" ||
@@ -83,34 +75,34 @@ export async function POST(request: Request) {
           : "balanced";
 
       if (enabled) {
-        if (!runwareApiKey) {
-          return new ChatSDKError("bad_request:api", "启用实时画布必须配置 Runware API Key").toResponse();
+        if (!bflApiKey) {
+          return new ChatSDKError("bad_request:api", "启用实时画布必须配置 BFL API Key").toResponse();
         }
-        for (const modelId of [runwareModel, runwareStylizeModel].filter(Boolean)) {
-          const probeResult = await probeRunwareSeedImageSupport({
-            apiKey: runwareApiKey,
-            modelId,
-          });
-          if (!probeResult.supported) {
-            return Response.json(
-              {
-                code: probeResult.code,
-                message: probeResult.message,
-              },
-              { status: mapProbeStatus(probeResult.code) }
-            );
-          }
+        const probeResult = await probeBflModelSupport({
+          apiKey: bflApiKey,
+          modelId: bflModel,
+          baseUrl: bflBaseUrl,
+        });
+        if (!probeResult.supported) {
+          return Response.json(
+            {
+              code: probeResult.code,
+              message: probeResult.message,
+            },
+            { status: mapProbeStatus(probeResult.code) }
+          );
         }
       }
 
       nextValue = {
         ...value,
-        runwareApiKey,
-        falApiKey: runwareApiKey,
-        runwareModel,
-        runwareStylizeModel,
-        runwareControlModel,
-        runwareControlPreprocessor,
+        bflApiKey,
+        bflModel,
+        bflBaseUrl,
+        runwareApiKey: bflApiKey,
+        falApiKey: bflApiKey,
+        apiKey: bflApiKey,
+        runwareModel: bflModel,
         renderMode,
       };
     }

app/api/realtime/config/route.ts

@@ -3,10 +3,11 @@ import { getSystemSetting } from "@/lib/db/queries";
 
 type RealtimeCanvasConfig = {
   enabled?: boolean;
+  bflApiKey?: string;
+  bflModel?: string;
+  bflBaseUrl?: string;
   runwareApiKey?: string;
   runwareModel?: string;
-  runwareControlModel?: string;
-  runwareControlPreprocessor?: "canny" | "lineart" | "depth";
   renderMode?: "strict-structure" | "balanced" | "stylize";
   falApiKey?: string;
   apiKey?: string;
@@ -38,15 +39,15 @@ const defaultConfig = {
     jpegQuality: 0.55,
   },
   model: {
-    id: "runware:101@1",
+    id: "flux-2-klein-4b",
     defaults: {
-      steps: 8,
+      steps: 3,
       cfgScale: 7,
       strength: 0.32,
       imageSize: "square" as const,
     },
     limits: {
-      steps: { min: 1, max: 12 },
+      steps: { min: 1, max: 6 },
       cfgScale: { min: 1, max: 14 },
       strength: { min: 0.05, max: 1.0 },
     },
@@ -77,20 +78,21 @@ export async function GET() {
     );
   }
 
-  const runwareApiKey = String(
-    config.runwareApiKey ||
+  const bflApiKey = String(
+    config.bflApiKey ||
+      config.runwareApiKey ||
       config.falApiKey ||
       config.apiKey ||
-      process.env.RUNWARE_API_KEY ||
-      process.env.RUNWARE_KEY ||
+      process.env.BFL_API_KEY ||
+      process.env.BFL_KEY ||
       ""
   ).trim();
 
-  if (!runwareApiKey) {
+  if (!bflApiKey) {
     return Response.json(
       {
-        code: "RUNWARE_KEY_MISSING",
-        message: "未配置 Runware API Key（请在服务器环境变量或设置中配置）",
+        code: "BFL_KEY_MISSING",
+        message: "未配置 BFL API Key（请在服务器环境变量或设置中配置）",
       },
       { status: 500 }
     );
@@ -138,13 +140,20 @@ export async function GET() {
   );
   const imageSize = config.defaults?.imageSize === "square_hd" ? "square_hd" : "square";
   const modelId = String(
-    config.runwareModel || process.env.RUNWARE_MODEL || defaultConfig.model.id
+    config.bflModel ||
+      config.runwareModel ||
+      process.env.BFL_MODEL ||
+      process.env.RUNWARE_MODEL ||
+      defaultConfig.model.id
   ).trim();
 
   return Response.json({
     ...defaultConfig,
     provider: {
-      type: "runware",
+      type: "bfl",
+      baseUrl:
+        String(config.bflBaseUrl || process.env.BFL_BASE_URL || "https://api.bfl.ai").trim() ||
+        "https://api.bfl.ai",
     },
     transport: {
       throttleInterval,
@@ -171,13 +180,5 @@ export async function GET() {
           ? config.renderMode
           : "balanced",
     },
-    control: {
-      model: String(config.runwareControlModel || "runware:25@1").trim() || "runware:25@1",
-      preprocessor:
-        config.runwareControlPreprocessor === "lineart" ||
-        config.runwareControlPreprocessor === "depth"
-          ? config.runwareControlPreprocessor
-          : "canny",
-    },
   });
 }

app/canvas/[id]/realtime/page.tsx

@@ -54,7 +54,7 @@ export default function CanvasRealtimePage() {
           status: "completed",
           title: "实时画布结果",
           prompt,
-          model: "fal-ai/flux-2/klein/realtime",
+          model: "bfl/flux-2",
         },
         connections: [],
       });

components/canvas/RealtimeCanvasDialog.tsx

@@ -96,9 +96,9 @@ const defaultRealtimeConfig: RealtimeConfig = {
     jpegQuality: 0.55,
   },
   model: {
-    id: "runware:101@1",
+    id: "flux-2-klein-4b",
     defaults: {
-      steps: 8,
+      steps: 3,
       cfgScale: 7,
       strength: 0.32,
       imageSize: "square",
@@ -1414,7 +1414,7 @@ export function RealtimeCanvasDialog({
 
         if (cancelled) return;
         connectionRef.current = {
-          provider: "runware",
+          provider: "bfl",
           modelId: resolvedConfig.model.id,
           reconnectToken: refreshToken,
         };

lib/realtime/bfl-capability.ts

@@ -0,0 +1,159 @@
+const DEFAULT_BFL_BASE_URL = "https://api.bfl.ai";
+const DEFAULT_BFL_MODEL_ID = "flux-2-klein-4b";
+const DEFAULT_TIMEOUT_MS = 15_000;
+
+export type BflCapabilityCode =
+  | "SUPPORTED"
+  | "AUTH_FAILED"
+  | "MODEL_INVALID"
+  | "UPSTREAM_ERROR";
+
+export type BflModelProbeResult = {
+  supported: boolean;
+  code: BflCapabilityCode;
+  message: string;
+  status?: number;
+};
+
+type BflProbeParams = {
+  apiKey: string;
+  modelId?: string;
+  baseUrl?: string;
+  timeoutMs?: number;
+};
+
+function normalizeBaseUrl(raw: string | undefined) {
+  const next = String(raw || DEFAULT_BFL_BASE_URL).trim();
+  return (next || DEFAULT_BFL_BASE_URL).replace(/\/+$/, "");
+}
+
+function encodeModelPath(modelId: string) {
+  return modelId
+    .split("/")
+    .filter(Boolean)
+    .map((part) => encodeURIComponent(part))
+    .join("/");
+}
+
+function toErrorMessage(payload: any, fallback: string) {
+  const direct = String(
+    payload?.error?.message ||
+      payload?.error ||
+      payload?.message ||
+      payload?.detail ||
+      payload?.msg ||
+      ""
+  ).trim();
+  return direct || fallback;
+}
+
+function looksLikeModelInvalid(message: string) {
+  const normalized = message.toLowerCase();
+  return (
+    normalized.includes("model") &&
+    (normalized.includes("not found") ||
+      normalized.includes("invalid") ||
+      normalized.includes("unknown") ||
+      normalized.includes("does not exist"))
+  );
+}
+
+function hasTaskIdentity(payload: any) {
+  return Boolean(
+    (typeof payload?.id === "string" && payload.id.trim()) ||
+      (typeof payload?.polling_url === "string" && payload.polling_url.trim()) ||
+      (typeof payload?.response?.id === "string" && payload.response.id.trim()) ||
+      (typeof payload?.response?.polling_url === "string" &&
+        payload.response.polling_url.trim())
+  );
+}
+
+export async function probeBflModelSupport(params: BflProbeParams): Promise<BflModelProbeResult> {
+  const apiKey = String(params.apiKey || "").trim();
+  const modelId = String(params.modelId || DEFAULT_BFL_MODEL_ID).trim() || DEFAULT_BFL_MODEL_ID;
+  const baseUrl = normalizeBaseUrl(params.baseUrl);
+  const timeoutMs = Math.max(3_000, Number(params.timeoutMs || DEFAULT_TIMEOUT_MS));
+
+  if (!apiKey) {
+    return {
+      supported: false,
+      code: "AUTH_FAILED",
+      message: "缺少 BFL API Key。",
+    };
+  }
+
+  const controller = new AbortController();
+  const timer = setTimeout(() => controller.abort(), timeoutMs);
+
+  try {
+    const endpoint = `${baseUrl}/v1/${encodeModelPath(modelId)}`;
+    const response = await fetch(endpoint, {
+      method: "POST",
+      headers: {
+        "x-key": apiKey,
+        "Content-Type": "application/json",
+        Accept: "application/json",
+      },
+      body: JSON.stringify({
+        prompt: "probe image generation capability",
+        width: 512,
+        height: 512,
+        safety_tolerance: 2,
+      }),
+      cache: "no-store",
+      signal: controller.signal,
+    });
+
+    const payload = await response.json().catch(() => null);
+    const message = toErrorMessage(payload, `BFL 探针请求失败（${response.status}）`);
+
+    if (response.ok && hasTaskIdentity(payload)) {
+      return {
+        supported: true,
+        code: "SUPPORTED",
+        message: "模型可用。",
+        status: response.status,
+      };
+    }
+
+    if (response.status === 401 || response.status === 403) {
+      return {
+        supported: false,
+        code: "AUTH_FAILED",
+        message: "BFL API Key 无效或无权限，请检查后重试。",
+        status: response.status,
+      };
+    }
+
+    if (response.status === 404 || looksLikeModelInvalid(message)) {
+      return {
+        supported: false,
+        code: "MODEL_INVALID",
+        message: `模型 ${modelId} 不存在或不可用，请更换模型后重试。`,
+        status: response.status,
+      };
+    }
+
+    return {
+      supported: false,
+      code: "UPSTREAM_ERROR",
+      message,
+      status: response.status,
+    };
+  } catch (error) {
+    if (error instanceof Error && error.name === "AbortError") {
+      return {
+        supported: false,
+        code: "UPSTREAM_ERROR",
+        message: "BFL 探针请求超时，请稍后重试。",
+      };
+    }
+    return {
+      supported: false,
+      code: "UPSTREAM_ERROR",
+      message: error instanceof Error ? error.message : "BFL 探针请求失败。",
+    };
+  } finally {
+    clearTimeout(timer);
+  }
+}