fix(agent-core/mcp): sanitize MCP JSON Schemas for Moonshot MFJS validator

.changeset/mfjs-schema-sanitize.md

@@ -0,0 +1,6 @@
+---
+"@moonshot-ai/agent-core-v2": patch
+"@moonshot-ai/kimi-code": patch
+---
+
+Sanitize circular and non-standard MCP JSON schemas and map disabled field to enabled in MCP config.

packages/agent-core-v2/src/human/eventStore/journal.ts

@@ -94,7 +94,7 @@ async function* readBranchChain(branch: Branch, tree: Tree): AsyncIterable<Journ
         : undefined;
     upto = parentSeq ?? null;
   }
-  for (const segment of chain.reverse()) {
+  for (const segment of chain.toReversed()) {
     for (const entry of segment.entries) {
       yield {
         branch: segment.name,

packages/agent-core-v2/src/human/llm-requester/retry.ts

@@ -7,7 +7,7 @@ const MAX_DELAY_MS = 32_000;
 const RETRY_FACTOR = 2;
 const JITTER_FACTOR = 0.25;
 
-const RETRYABLE_STATUS_CODES: readonly number[] = [408, 409, 429, 500, 502, 503, 504, 529];
+const RETRYABLE_STATUS_CODES: readonly number[] = new Set([408, 409, 429, 500, 502, 503, 504, 529]);
 
 export interface LlmRetryOptions {
   readonly maxAttemptsPerStep?: number;
@@ -50,7 +50,7 @@ export function isRetryableError(error: LlmErrorMessage): boolean {
     case 'empty_response':
       return error.finishReason !== 'filtered';
     case 'status':
-      return RETRYABLE_STATUS_CODES.includes(error.statusCode);
+      return RETRYABLE_STATUS_CODES.has(error.statusCode);
     default:
       return true;
   }

packages/agent-core-v2/src/human/llm/message.ts

@@ -361,7 +361,7 @@ export function createMessageAccumulator(): MessageAccumulator {
         return undefined;
       }
       flush();
-      return message.toolCalls[message.toolCalls.length - 1];
+      return message.toolCalls.at(-1);
     },
     finish(): AssistantMessage {
       flush();

packages/agent-core-v2/src/human/persist/v2/fold.ts

@@ -188,9 +188,9 @@ function truncateTextToTokensFromEnd(text: string, maxTokens: number): string {
   let start = text.length;
   for (let i = text.length - 1; i >= 0; i--) {
     let isAscii = false;
-    const code = text.charCodeAt(i);
+    const code = text.codePointAt(i);
     if (code >= 0xdc00 && code <= 0xdfff && i > 0) {
-      const high = text.charCodeAt(i - 1);
+      const high = text.codePointAt(i - 1);
       if (high >= 0xd800 && high <= 0xdbff) {
         i--;
       }

packages/agent-core-v2/src/mcpCore/config-schema.ts

@@ -58,7 +58,10 @@ const McpServerConfigDiscriminatedSchema = z.discriminatedUnion('transport', [
 
 export const McpServerConfigSchema = z.preprocess((raw) => {
   if (typeof raw !== 'object' || raw === null || Array.isArray(raw)) return raw;
-  const obj = raw as Record<string, unknown>;
+  const obj = { ...(raw as Record<string, unknown>) };
+  if ('disabled' in obj && !('enabled' in obj) && typeof obj['disabled'] === 'boolean') {
+    obj['enabled'] = !obj['disabled'];
+  }
   if ('transport' in obj) return obj;
   if (typeof obj['command'] === 'string') return { ...obj, transport: 'stdio' };
   if (typeof obj['url'] === 'string') return { ...obj, transport: 'http' };

packages/agent-core-v2/src/mcpCore/connection-manager.ts

@@ -20,6 +20,7 @@ import {
 } from './client-shared';
 import { StdioMcpClient } from './client-stdio';
 import type { McpOAuthService } from '#/mcpCore/oauth/service';
+import { sanitizeMcpSchema } from './schema-sanitize';
 import { assertMcpInputSchema, type MCPClient, type MCPToolDefinition } from './types';
 
 export type McpServerStatus = 'pending' | 'connected' | 'failed' | 'disabled' | 'needs-auth' | 'removed';
@@ -869,7 +870,7 @@ export class McpConnectionManager implements McpConnectionView {
         tools: mcpTools.map((mcpTool) => ({
           name: mcpTool.name,
           description: mcpTool.description,
-          parameters: assertMcpInputSchema(mcpTool.name, mcpTool.inputSchema),
+          parameters: sanitizeMcpSchema(assertMcpInputSchema(mcpTool.name, mcpTool.inputSchema)),
         })),
       };
     } catch (error) {