fix(xiaoyunque): harden generation prompt handling

packages/plugins/xiaoyunque-generation/convax-package.json

@@ -4,7 +4,7 @@
   "id": "xiaoyunque-generation",
   "name": "小云雀生成",
   "description": "通过宿主管理的小云雀网页授权展示服务状态，并使用小云雀第一方网页能力生成图片和视频。",
-  "version": "0.3.5",
+  "version": "0.3.6",
   "license": "MIT",
   "compatibility": {
     "pluginSchema": "convax.plugin/3",
@@ -13,7 +13,7 @@
   "companions": [
     {
       "command": "convax-xiaoyunque-mcp",
-      "version": "0.3.3",
+      "version": "0.3.4",
       "source": "packages/tools/xiaoyunque-mcp",
       "targets": [
         {

packages/plugins/xiaoyunque-generation/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@microvoid/convax-plugin-xiaoyunque-generation",
-  "version": "0.3.5",
+  "version": "0.3.6",
   "private": true,
   "type": "module",
   "dependencies": {

packages/plugins/xiaoyunque-generation/package/manifest.json

@@ -3,7 +3,7 @@
   "id": "xiaoyunque-generation",
   "name": "小云雀生成",
   "description": "通过宿主管理的小云雀网页授权展示服务状态，并使用小云雀第一方网页能力生成图片和视频。",
-  "version": "0.3.5",
+  "version": "0.3.6",
   "contributes": {
     "generation": {
       "models": [

packages/tools/xiaoyunque-mcp/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@microvoid/convax-xiaoyunque-mcp",
-  "version": "0.3.3",
+  "version": "0.3.4",
   "private": true,
   "type": "module",
   "bin": {

packages/tools/xiaoyunque-mcp/scripts/live-image-smoke.ts

@@ -55,7 +55,7 @@ function notify(method: string, params: unknown) {
 try {
   const initialized = await request("initialize", {
     capabilities: {},
-    clientInfo: { name: "convax-xiaoyunque-live-smoke", version: "0.3.3" },
+    clientInfo: { name: "convax-xiaoyunque-live-smoke", version: "0.3.4" },
     protocolVersion: "2025-03-26",
   })
   if ((initialized.result as Record<string, unknown> | undefined)?.protocolVersion !== "2025-03-26") {

packages/tools/xiaoyunque-mcp/scripts/live-video-smoke.ts

@@ -117,7 +117,7 @@ try {
   progress("mcp.initialize")
   const initialized = await request("initialize", {
     capabilities: {},
-    clientInfo: { name: "convax-xiaoyunque-live-video-smoke", version: "0.3.3" },
+    clientInfo: { name: "convax-xiaoyunque-live-video-smoke", version: "0.3.4" },
     protocolVersion: "2025-03-26",
   })
   if ((initialized.result as Record<string, unknown> | undefined)?.protocolVersion !== "2025-03-26") {

packages/tools/xiaoyunque-mcp/src/contracts.ts

@@ -9,6 +9,15 @@ const authorizationIdPattern = /^[A-Za-z0-9_-]{16,128}$/u
 const cookieNamePattern = /^[!#$%&'*+\-.^_`|~0-9A-Za-z]{1,128}$/u
 const maximumCookieValueBytes = 16 * 1024
 const maximumCookieBytes = 32 * 1024
+export const maximumGenerationPromptBytes = 20_000
+
+export class XiaoYunquePromptTooLongError extends Error {
+  override name = "XiaoYunquePromptTooLongError"
+
+  constructor() {
+    super("XiaoYunque generation prompt is too long")
+  }
+}
 
 export type GenerationOutput = "image" | "video"
 export type GenerationReferenceRole =
@@ -215,6 +224,21 @@ function requireTrimmedText(value: unknown, label: string, maxLength: number) {
   return value
 }
 
+export function parseGenerationPrompt(value: unknown) {
+  if (
+    typeof value !== "string"
+    || value.length === 0
+    || value !== value.trim()
+    || /[\u0000-\u0008\u000b\u000c\u000e-\u001f\u007f]/u.test(value)
+  ) {
+    throw new Error("generation prompt must be non-empty trimmed text")
+  }
+  if (Buffer.byteLength(value, "utf8") > maximumGenerationPromptBytes) {
+    throw new XiaoYunquePromptTooLongError()
+  }
+  return value
+}
+
 const referenceRoles = new Set<GenerationReferenceRole>([
   "reference_image",
   "reference_video",
@@ -268,7 +292,7 @@ export function parseGenerationCall(value: unknown, expectedOutput: GenerationOu
     operation_id: requireTrimmedString(input.operation_id, "generation operation_id", 256),
     output: expectedOutput,
     output_directory: requireTrimmedString(input.output_directory, "generation output_directory", 4_096),
-    prompt: requireTrimmedText(input.prompt, "generation prompt", 20_000),
+    prompt: parseGenerationPrompt(input.prompt),
     references,
     schema: generationCallSchema,
   }

packages/tools/xiaoyunque-mcp/src/generator.ts

@@ -65,6 +65,22 @@ export class XiaoYunqueUnsupportedImageModelError extends Error {
   }
 }
 
+export type XiaoYunqueTerminalGenerationReason =
+  | "failed"
+  | "cancelled"
+  | "additional-input"
+  | "human-input"
+
+export class XiaoYunqueTerminalGenerationError extends Error {
+  override name = "XiaoYunqueTerminalGenerationError"
+  readonly reason: XiaoYunqueTerminalGenerationReason
+
+  constructor(reason: XiaoYunqueTerminalGenerationReason) {
+    super(`XiaoYunque generation entered terminal state: ${reason}`)
+    this.reason = reason
+  }
+}
+
 function abortError() {
   return new DOMException("Generation was cancelled", "AbortError")
 }
@@ -313,13 +329,13 @@ export class GenerationEngine {
         if (result.terminalDiagnosticCode === "unsupported-image-model") {
           throw new XiaoYunqueUnsupportedImageModelError()
         }
-        throw new Error(result.error || `XiaoYunque ${output} generation failed`)
+        throw new XiaoYunqueTerminalGenerationError(result.state === 4 ? "failed" : "cancelled")
       }
       if (result.state === 6) {
-        throw new Error(`XiaoYunque ${output} generation requires additional input`)
+        throw new XiaoYunqueTerminalGenerationError("additional-input")
       }
       if (result.state === 9) {
-        throw new Error(result.error || `XiaoYunque ${output} generation was interrupted for human input`)
+        throw new XiaoYunqueTerminalGenerationError("human-input")
       }
       await abortableDelay(this.#pollIntervalMs, signal)
     }

packages/tools/xiaoyunque-mcp/src/mcp-server.ts

@@ -4,6 +4,7 @@ import {
   type GenerationCall,
   type JsonRpcRequest,
   parseGenerationCall,
+  XiaoYunquePromptTooLongError,
   parsePluginServiceBrowserAuthorizationCompletion,
   type PluginServiceBrowserAuthorizationCompletion,
   type PluginServiceBrowserAuthorizationRequest,
@@ -14,6 +15,7 @@ import { XiaoYunqueCredentialConfigurationError } from "./configuration-error.ts
 import {
   XiaoYunqueGenerationInputError,
   XiaoYunqueObservationRejectedError,
+  XiaoYunqueTerminalGenerationError,
   XiaoYunqueUnsupportedImageModelError,
 } from "./generator.ts"
 import {
@@ -140,6 +142,9 @@ function isJsonRpcRequest(value: unknown): value is JsonRpcRequest {
 export function publicGenerationErrorMessage(error: unknown) {
   if (error instanceof XiaoYunqueCredentialConfigurationError) return error.publicMessage
   if (error instanceof XiaoYunqueGenerationInputError) return error.publicMessage
+  if (error instanceof XiaoYunquePromptTooLongError) {
+    return "The XiaoYunque prompt is too long. Shorten the prompt or remove some @ text context and try again."
+  }
   if (error instanceof XiaoYunqueAuthenticationError) {
     return "XiaoYunque sign-in expired. Open Convax Services and reconnect XiaoYunque."
   }
@@ -152,6 +157,18 @@ export function publicGenerationErrorMessage(error: unknown) {
   if (error instanceof XiaoYunqueUnsupportedImageModelError) {
     return "The selected XiaoYunque image model is no longer available. Choose another image model and try again."
   }
+  if (error instanceof XiaoYunqueTerminalGenerationError) {
+    if (error.reason === "failed") {
+      return "XiaoYunque accepted the generation, but the service reported that it failed. Check XiaoYunque before starting another paid generation."
+    }
+    if (error.reason === "cancelled") {
+      return "XiaoYunque accepted the generation, but the service reported that it was cancelled. Check XiaoYunque before starting another paid generation."
+    }
+    if (error.reason === "additional-input") {
+      return "XiaoYunque accepted the generation, but it requires additional input in XiaoYunque. Complete it there before starting another paid generation."
+    }
+    return "XiaoYunque accepted the generation, but it was interrupted for human input. Check XiaoYunque before starting another paid generation."
+  }
   if (error instanceof XiaoYunqueReferenceAssetRegistrationError) {
     return error.referenceType === "video"
       ? "XiaoYunque could not prepare the reference video for generation. No generation was submitted; try again."
@@ -166,10 +183,15 @@ export function publicGenerationErrorMessage(error: unknown) {
 export const safeGenerationDiagnosticCodes = [
   "local-setup-required",
   "local-input-rejected",
+  "prompt-too-long",
   "sign-in-expired",
   "status-check-rejected",
   "status-check-timeout",
   "unsupported-image-model",
+  "generation-failed",
+  "generation-cancelled",
+  "generation-input-required",
+  "generation-interrupted",
   "reference-image-registration-failed",
   "reference-video-registration-failed",
   "upstream-envelope-rejected",
@@ -183,10 +205,20 @@ export type SafeGenerationDiagnosticCode = typeof safeGenerationDiagnosticCodes[
 export function safeGenerationDiagnosticCode(error: unknown): SafeGenerationDiagnosticCode {
   if (error instanceof XiaoYunqueCredentialConfigurationError) return "local-setup-required"
   if (error instanceof XiaoYunqueGenerationInputError) return "local-input-rejected"
+  if (error instanceof XiaoYunquePromptTooLongError) return "prompt-too-long"
   if (error instanceof XiaoYunqueAuthenticationError) return "sign-in-expired"
   if (error instanceof XiaoYunqueObservationRejectedError) return "status-check-rejected"
   if (error instanceof XiaoYunqueQueryTimeoutError) return "status-check-timeout"
   if (error instanceof XiaoYunqueUnsupportedImageModelError) return "unsupported-image-model"
+  if (error instanceof XiaoYunqueTerminalGenerationError) {
+    return error.reason === "failed"
+      ? "generation-failed"
+      : error.reason === "cancelled"
+        ? "generation-cancelled"
+        : error.reason === "additional-input"
+          ? "generation-input-required"
+          : "generation-interrupted"
+  }
   if (error instanceof XiaoYunqueReferenceAssetRegistrationError) {
     return error.referenceType === "video"
       ? "reference-video-registration-failed"
@@ -309,7 +341,7 @@ export class McpServer {
       this.#sendResult(request.id, {
         capabilities: { tools: {} },
         protocolVersion,
-        serverInfo: { name: "convax-xiaoyunque-mcp", version: "0.3.3" },
+        serverInfo: { name: "convax-xiaoyunque-mcp", version: "0.3.4" },
       })
       return
     }

packages/tools/xiaoyunque-mcp/src/xiaoyunque-api.ts

@@ -1,6 +1,10 @@
 import { randomUUID } from "node:crypto"
 import { lstat } from "node:fs/promises"
-import type { FileGenerationReference, GenerationOutput } from "./contracts.ts"
+import {
+  type FileGenerationReference,
+  type GenerationOutput,
+  parseGenerationPrompt,
+} from "./contracts.ts"
 import type { XiaoYunqueImageModel, XiaoYunqueVideoModel } from "./models.ts"
 import {
   type StoredWebSession,
@@ -274,6 +278,10 @@ async function boundedJson(response: Response, label: string) {
     await response.body?.cancel().catch(() => undefined)
     throw new XiaoYunqueAuthenticationError("XiaoYunque authorization is no longer valid")
   }
+  if (response.status < 200 || response.status >= 300) {
+    await response.body?.cancel().catch(() => undefined)
+    throw new XiaoYunqueRequestRejectedError(`${label} was rejected`, "upstream-http-rejected")
+  }
   const declaredLength = response.headers.get("content-length")
   if (declaredLength !== null) {
     const parsed = Number(declaredLength)
@@ -697,7 +705,7 @@ export class XiaoYunqueApi {
     session: StoredWebSession,
     signal: AbortSignal,
   ): Promise<RemoteTask> {
-    const prompt = boundedText(options.prompt.trim(), "XiaoYunque image prompt", 32_768)
+    const prompt = parseGenerationPrompt(options.prompt.trim())
     if (options.assets.length > 9) throw new Error("XiaoYunque accepts at most nine reference images")
     const task = { runId: randomUUID(), threadId: randomUUID() }
     const agentName = "pippit_novel_agent_cn_v2"
@@ -744,7 +752,7 @@ export class XiaoYunqueApi {
     session: StoredWebSession,
     signal: AbortSignal,
   ): Promise<RemoteTask> {
-    const prompt = boundedText(options.prompt.trim(), "XiaoYunque video prompt", 32_768)
+    const prompt = parseGenerationPrompt(options.prompt.trim())
     const maximumImages = options.model === "Seedance_1.0_fast" ? 1 : 9
     if (options.imageAssets.length > maximumImages) {
       throw new Error(`XiaoYunque ${options.model} accepts at most ${maximumImages} reference image${maximumImages === 1 ? "" : "s"}`)

packages/tools/xiaoyunque-mcp/test/contracts.test.ts

@@ -1,5 +1,9 @@
 import { describe, expect, test } from "bun:test"
-import { parseGenerationCall } from "../src/contracts.ts"
+import {
+  maximumGenerationPromptBytes,
+  parseGenerationCall,
+  XiaoYunquePromptTooLongError,
+} from "../src/contracts.ts"
 
 function generationCall(prompt: string, text = "reference line one\n\treference line two") {
   return {
@@ -36,4 +40,16 @@ describe("XiaoYunque generation call contract", () => {
         .toThrow()
     },
   )
+
+  test("bounds prompts by UTF-8 bytes instead of JavaScript characters", () => {
+    const exactAscii = "a".repeat(maximumGenerationPromptBytes)
+    const exactChinese = "画".repeat(Math.floor(maximumGenerationPromptBytes / 3))
+
+    expect(parseGenerationCall(generationCall(exactAscii), "image").prompt).toBe(exactAscii)
+    expect(parseGenerationCall(generationCall(exactChinese), "image").prompt).toBe(exactChinese)
+    expect(() => parseGenerationCall(generationCall(`${exactAscii}a`), "image"))
+      .toThrow(XiaoYunquePromptTooLongError)
+    expect(() => parseGenerationCall(generationCall(`${exactChinese}画`), "image"))
+      .toThrow(XiaoYunquePromptTooLongError)
+  })
 })

packages/tools/xiaoyunque-mcp/test/generator.test.ts

@@ -7,6 +7,7 @@ import {
   GenerationEngine,
   XiaoYunqueGenerationInputError,
   XiaoYunqueObservationRejectedError,
+  XiaoYunqueTerminalGenerationError,
   XiaoYunqueUnsupportedImageModelError,
 } from "../src/generator.ts"
 import { fingerprintGenerationCall, OperationStore } from "../src/operation-store.ts"
@@ -1082,8 +1083,17 @@ describe("XiaoYunque generation engine", () => {
         output_directory: output,
       }), videoModel, new AbortController().signal).catch((error: unknown) => error)
 
-      expect(failure).toBeInstanceOf(Error)
-      expect((failure as Error).message).toBe(terminal.message)
+      expect(failure).toBeInstanceOf(XiaoYunqueTerminalGenerationError)
+      expect((failure as XiaoYunqueTerminalGenerationError).reason).toBe(
+        terminal.state === "4"
+          ? "failed"
+          : terminal.state === "5"
+            ? "cancelled"
+            : terminal.state === "6"
+              ? "additional-input"
+              : "human-input",
+      )
+      expect((failure as Error).message).not.toContain("at the vendor")
       expect(queryCount).toBe(1)
     })
   }
@@ -1176,8 +1186,10 @@ describe("XiaoYunque generation engine", () => {
         output_directory: output,
       }), imageModel, new AbortController().signal).catch((error: unknown) => error)
 
-      expect(failure).toBeInstanceOf(Error)
-      expect((failure as Error).message).toBe(terminal.message)
+      expect(failure).toBeInstanceOf(XiaoYunqueTerminalGenerationError)
+      expect((failure as XiaoYunqueTerminalGenerationError).reason).toBe(
+        terminal.state === 6 ? "additional-input" : "human-input",
+      )
       expect(queryCount).toBe(1)
     })
   }

packages/tools/xiaoyunque-mcp/test/mcp-process.test.ts

@@ -253,7 +253,7 @@ describe("MCP process", () => {
       })
       expect(initialized).toMatchObject({
         result: {
-          serverInfo: { name: "convax-xiaoyunque-mcp", version: "0.3.3" },
+          serverInfo: { name: "convax-xiaoyunque-mcp", version: "0.3.4" },
         },
       })
       const authorization = await harness.request("tools/call", { name: "service.authorize", arguments: {} })