diff --git a/app/api/canvas/world/tasks/route.ts b/app/api/canvas/world/tasks/route.ts
index 314b1c3a6..3ddcd7fe5 100644
--- a/app/api/canvas/world/tasks/route.ts
+++ b/app/api/canvas/world/tasks/route.ts
@@ -142,14 +142,14 @@ function shouldUseExternalTaskCreateApi(
   config: Awaited<ReturnType<typeof getWorldLabsProviderConfig>>,
   mode: WorldTaskMode
 ) {
-  return isWorldLabsExternalTaskApi(config.baseUrl) && mode === "text";
+  return isWorldLabsExternalTaskApi(config.baseUrl) && mode === "image";
 }
 
 function isWorldLabsModeUnsupportedByExternalProvider(
   config: Awaited<ReturnType<typeof getWorldLabsProviderConfig>>,
   mode: WorldTaskMode
 ) {
-  return isWorldLabsExternalTaskApi(config.baseUrl) && mode !== "text";
+  return isWorldLabsExternalTaskApi(config.baseUrl) && mode !== "image";
 }
 
 function assertWorldModeSupportedByCandidate(
@@ -160,7 +160,7 @@ function assertWorldModeSupportedByCandidate(
     const normalizedBaseUrl = String(config.baseUrl || "").trim() || "未知服务地址";
     const normalizedMode = String(mode || "").trim() || "未知模式";
     throw new Error(
-      `${normalizedBaseUrl} 的 world-generation 当前仅支持文生世界（text）。当前提交的是 ${normalizedMode}，请先切换供应商或使用文生世界。`
+      `${normalizedBaseUrl} 的 world-generation 当前仅支持图生世界（image）。当前提交的是 ${normalizedMode}，请先切换供应商或使用图生世界。`
     );
   }
 }
@@ -173,6 +173,33 @@ function resolveOfficialMarbleModel(model?: string | null) {
   return normalized;
 }
 
+function buildExternalWorldTaskPayload(
+  mode: WorldTaskMode,
+  worldPrompt: Record<string, unknown>,
+  prompt: string | null,
+  displayName: string,
+) {
+  const normalizedPrompt = readOptionalTrimmedText(prompt);
+  if (!normalizedPrompt && mode === "text") {
+    throw new Error("请输入世界描述");
+  }
+  const payload: Record<string, unknown> = {
+    model: WORLDLABS_EXTERNAL_TASK_MODEL,
+    displayName,
+  };
+  if (normalizedPrompt) {
+    payload.prompt = normalizedPrompt;
+  } else if (mode !== "text") {
+    payload.prompt = "图生世界";
+  }
+
+  if (mode === "image" || mode === "multi-image") {
+    payload.world_prompt = worldPrompt;
+  }
+
+  return payload;
+}
+
 function buildWorldPrompt(body: CreateWorldTaskRequest, mode: WorldTaskMode) {
   const textPrompt = readOptionalTrimmedText(body.prompt);
 
@@ -378,21 +405,19 @@ export async function POST(request: Request) {
         const useExternalTaskApi = shouldUseExternalTaskCreateApi(candidate, mode);
         assertWorldModeSupportedByCandidate(candidate, mode);
         if (useExternalTaskApi) {
-          const prompt = readOptionalTrimmedText(body.prompt);
-          if (!prompt) {
-            throw new Error("请输入世界描述");
-          }
+          const payload = buildExternalWorldTaskPayload(
+            mode,
+            worldPrompt,
+            readOptionalTrimmedText(body.prompt),
+            displayName,
+          );
           const externalResult = await worldLabsRequest<
             WorldLabsExternalTaskResponse<WorldLabsExternalTaskCreateData>
           >(candidate, {
             method: "POST",
             path: "/api/external/task/generate",
             timeoutMs: resolveWorldLabsCreateTimeoutMs(),
-            json: {
-              model: WORLDLABS_EXTERNAL_TASK_MODEL,
-              displayName,
-              prompt,
-            },
+            json: payload,
           });
           result = normalizeExternalTaskCreateOperation(externalResult);
         } else {