抠图输入超限返回明确的请求错误状态

app/api/canvas/[id]/capabilities/route.ts

@@ -2,6 +2,7 @@ import { NextResponse } from "next/server";
 import { ZodError } from "zod";
 
 import { auth } from "@/app/(auth)/auth";
+import { RmbgServiceError } from "@/lib/ai/rmbg/service";
 import { canvasCapabilityClientCommandSchema } from "@/lib/canvas/capabilities/client-command";
 import { CanvasCapabilityRuntimeError } from "@/lib/canvas/capabilities/context";
 import { getCanvasCapabilityManifest } from "@/lib/canvas/capabilities/registry";
@@ -90,7 +91,7 @@ export async function POST(
     const failure = getRequestFailureDetails(error, "执行画布能力失败");
     return NextResponse.json(
       { success: false, error: formatRequestFailure(failure, requestId), failure, requestId },
-      { status: 500 }
+      { status: error instanceof RmbgServiceError ? error.status : 500 }
     );
   }
 }

tests/routes/rmbg-delivery.test.ts

@@ -133,6 +133,31 @@ test("AOS input rejections retain their cause instead of becoming a generic proc
   }
 });
 
+test("the canvas API returns input-limit errors as HTTP 400 and preserves the same advice when polling", async () => {
+  const service = rmbgLoader(async () => { throw new Error("Unexpected provider call"); });
+  const error = new service.RmbgServiceError("抠图参考图分辨率超限（5056×3392 像素），当前 AOS 上游要求宽、高均不超过 4096 像素。", 400);
+  const route = serverLoader({
+    "@/app/(auth)/auth": { auth: async () => ({ user: { id: "user-a" } }) },
+    "@/lib/ai/rmbg/service": { RmbgServiceError: service.RmbgServiceError },
+    "@/lib/canvas/capabilities/client-command": { canvasCapabilityClientCommandSchema: { parse: (v: unknown) => v } },
+    "@/lib/canvas/capabilities/context": { CanvasCapabilityRuntimeError: class extends Error {} },
+    "@/lib/canvas/agent-mutations": { CanvasAgentMutationError: class extends Error {} },
+    "@/lib/canvas/capabilities/registry": { getCanvasCapabilityManifest: () => [] },
+    "@/lib/canvas/capabilities/runtime": { executeCanvasCapabilityRuntime: async () => { throw error; } },
+    "@/lib/canvas/capabilities/task-store": { getCanvasCapabilityTask: async () => ({ id: "task-a", status: "failed", error: error.message }) },
+  })("app/api/canvas/[id]/capabilities/route.ts");
+  const params = { params: Promise.resolve({ id: "project-a" }) };
+  const response = await route.POST(new Request("https://example.com/api/canvas/project-a/capabilities", { method: "POST", body: JSON.stringify({ requestId: "request-a" }) }), params);
+  expect(response.status).toBe(400);
+  const submitted = await response.json();
+  expect(submitted.failure).toMatchObject({ code: "RMBG_INPUT_RESOLUTION_EXCEEDED", outcome: "failed" });
+  expect(submitted.error).toContain("5056×3392");
+  expect(submitted.error).toContain("本次未提交上游抠图任务");
+  const polled = await (await route.GET(new Request("https://example.com/api/canvas/project-a/capabilities?requestId=request-a"), params)).json();
+  expect(polled.task.failure).toEqual(submitted.failure);
+  expect(polled.task.error).toContain(submitted.failure.recommendation);
+});
+
 test("a create timeout preserves its cause and never creates another paid task", async () => {
   const image = await sharp({ create: { width: 16, height: 16, channels: 3, background: "white" } }).png().toBuffer();
   let creates = 0;