diff --git a/AGENTS.md b/AGENTS.md
index d8e25a3..74e0458 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -29,7 +29,7 @@
 <!-- gitnexus:start -->
 # GitNexus — Code Intelligence
 
-This project is indexed by GitNexus as **a-share-analysis** (2358 symbols, 3190 relationships, 65 execution flows). Use the GitNexus MCP tools to understand code, assess impact, and navigate safely.
+This project is indexed by GitNexus as **a-share-analysis** (2373 symbols, 3222 relationships, 63 execution flows). Use the GitNexus MCP tools to understand code, assess impact, and navigate safely.
 
 > If any GitNexus tool warns the index is stale, run `npx gitnexus analyze` in terminal first.
 
diff --git a/tools/database/mysql2-schema-exporter.mjs b/tools/database/mysql2-schema-exporter.mjs
index 6643bd2..f84535b 100644
--- a/tools/database/mysql2-schema-exporter.mjs
+++ b/tools/database/mysql2-schema-exporter.mjs
@@ -136,9 +136,9 @@ async function queryCatalogRows(connection, sql, database, limits) {
       values: [database],
       timeout: limits.queryTimeoutMs,
     });
-  } catch {
+  } catch (error) {
     // mysql2 错误可能包含连接 URL、用户名或密码，目录读取的公共接口一律不透传原始文本。
-    throw new SchemaExportError('DATABASE_QUERY_FAILED', '开发库 Schema 查询失败');
+    sanitizeDatabaseQueryError(error);
   }
   if (!Array.isArray(result) || !Array.isArray(result[0])) {
     throw new SchemaExportError('CATALOG_SHAPE_INVALID', 'Schema 对象目录查询结果无效');
@@ -302,6 +302,19 @@ function maskStringLiterals(sql) {
   return String(sql).replace(/'(?:''|\\.|[^'\\])*'/gs, "''");
 }
 
+function removeTableAutoIncrementOutsideLiterals(sql) {
+  const literals = [];
+  const masked = String(sql).replace(/'(?:''|\\.|[^'\\])*'/gs, (literal) => {
+    const index = literals.push(literal) - 1;
+    return `\u0001${index}\u0002`;
+  });
+  const cleaned = masked.replace(
+    /\sAUTO_INCREMENT=\d+(?=\s(?:DEFAULT\s+)?CHARSET=)/i,
+    '',
+  );
+  return cleaned.replace(/\u0001(\d+)\u0002/g, (_match, index) => literals[Number(index)]);
+}
+
 /**
  * SHOW CREATE 的格式由服务端决定，这里只移除与结构无关的账号绑定、当前表自增值、
  * 行尾分号和换行差异，不重排对象体，也不删除字符串字面量中的业务文本。
@@ -313,20 +326,26 @@ export function normalizeCreateDefinition(definition) {
       /^(CREATE\s+(?:ALGORITHM=\S+\s+)?)DEFINER=`(?:``|[^`])+`@`(?:`(?:``|[^`])+`|'(?:''|[^'])+'|\S+)\s+/i,
       '$1',
     )
-    .replace(/\sAUTO_INCREMENT=\d+(?=\s(?:DEFAULT\s+)?CHARSET=)/i, '')
     .trim()
     .replace(/;+\s*$/, '');
-  const inspectable = maskStringLiterals(normalized);
+  const withoutCurrentAutoIncrement = removeTableAutoIncrementOutsideLiterals(normalized);
+  const inspectable = maskStringLiterals(withoutCurrentAutoIncrement);
   if (
     /\bDEFINER\s*=/i.test(inspectable) ||
     /\b(?:password|passwd|pwd|api[_-]?key|api[_-]?token|access[_-]?token|client[_-]?secret|secret)\s*[:=]/i.test(
       inspectable,
     ) ||
-    /\b(?:mysql|mariadb):\/\/[^\s'"`]+/i.test(inspectable)
+    /\b(?:mysql|mariadb):\/\/[^\s'"`]+/i.test(inspectable) ||
+    /(?:--|\/\*)\s*(?:host|hostname|server)\s*[:=]\s*[^\s*]+/i.test(inspectable)
   ) {
     throw new SchemaExportError('UNSAFE_DEFINITION', 'Schema 对象定义包含禁止内容');
   }
-  return normalized;
+  return withoutCurrentAutoIncrement;
+}
+
+function sanitizeDatabaseQueryError(error) {
+  if (error instanceof SchemaExportError) throw error;
+  throw new SchemaExportError('DATABASE_QUERY_FAILED', '开发库 Schema 查询失败');
 }
 
 export async function readMysql57ServerMetadata(
@@ -334,11 +353,16 @@ export async function readMysql57ServerMetadata(
   database,
   limits = DEFAULT_EXPORT_LIMITS,
 ) {
-  const [rows] = await connection.query({
-    sql: SERVER_METADATA_QUERY,
-    values: [database],
-    timeout: limits.queryTimeoutMs,
-  });
+  let rows;
+  try {
+    [rows] = await connection.query({
+      sql: SERVER_METADATA_QUERY,
+      values: [database],
+      timeout: limits.queryTimeoutMs,
+    });
+  } catch (error) {
+    sanitizeDatabaseQueryError(error);
+  }
   if (!Array.isArray(rows) || rows.length !== 1) {
     throw new SchemaExportError('DATABASE_METADATA_INVALID', '开发库元数据查询结果无效');
   }
@@ -365,7 +389,12 @@ function getCreateDescriptors(catalog) {
 
 async function readCreateDefinition(connection, descriptor, limits) {
   const sql = `SHOW CREATE ${descriptor.type} ${quoteIdentifier(DEVELOPMENT_DATABASE)}.${quoteIdentifier(descriptor.name)}`;
-  const [rows] = await connection.query({ sql, timeout: limits.queryTimeoutMs });
+  let rows;
+  try {
+    [rows] = await connection.query({ sql, timeout: limits.queryTimeoutMs });
+  } catch (error) {
+    sanitizeDatabaseQueryError(error);
+  }
   if (!Array.isArray(rows) || rows.length === 0) {
     throw new SchemaExportError('SHOW_CREATE_EMPTY', 'SHOW CREATE 未返回对象定义');
   }
diff --git a/tools/database/mysql2-schema-exporter.test.mjs b/tools/database/mysql2-schema-exporter.test.mjs
index 472525e..d848fdb 100644
--- a/tools/database/mysql2-schema-exporter.test.mjs
+++ b/tools/database/mysql2-schema-exporter.test.mjs
@@ -494,6 +494,20 @@ test('定义规范化只移除账号绑定和当前自增值', () => {
   );
 });
 
+test('规范化保留例程中的自增文本并拒绝主机信息', () => {
+  const routine = normalizeCreateDefinition(
+    "CREATE PROCEDURE `sample`() SELECT ' AUTO_INCREMENT=123 DEFAULT CHARSET=utf8mb4'",
+  );
+  assert.equal(
+    routine,
+    "CREATE PROCEDURE `sample`() SELECT ' AUTO_INCREMENT=123 DEFAULT CHARSET=utf8mb4'",
+  );
+  assert.throws(
+    () => normalizeCreateDefinition('CREATE TABLE `sample` (`id` int) /* Host: prod-db.internal */'),
+    (error) => error.code === 'UNSAFE_DEFINITION',
+  );
+});
+
 test('完整导出双重读取一致并始终关闭连接', async () => {
   const connection = createExportConnection();
   let receivedOptions;
@@ -592,6 +606,29 @@ test('SHOW CREATE 拒绝空结果、错误形状和过大定义', async () => {
   );
 });
 
+test('直接元数据和 SHOW CREATE 查询错误统一脱敏且保留既有业务错误', async () => {
+  const rawFailure = new Error('host=prod-db.internal password=not-for-logs');
+  await assert.rejects(
+    () => readMysql57ServerMetadata({ query: async () => { throw rawFailure; } }, 'a_share_analysis_dev'),
+    (error) =>
+      error.code === 'DATABASE_QUERY_FAILED' &&
+      !error.message.includes('prod-db.internal') &&
+      !error.message.includes('not-for-logs'),
+  );
+  await assert.rejects(
+    () => readDefinitions({ query: async () => { throw rawFailure; } }, completeCatalog),
+    (error) =>
+      error.code === 'DATABASE_QUERY_FAILED' &&
+      !error.message.includes('prod-db.internal') &&
+      !error.message.includes('not-for-logs'),
+  );
+  const timeout = new SchemaExportError('EXPORT_TIMEOUT', 'Schema 导出超过总时长限制');
+  await assert.rejects(
+    () => readDefinitions({ query: async () => { throw timeout; } }, completeCatalog),
+    (error) => error === timeout,
+  );
+});
+
 test('查询失败和总超时只返回脱敏错误并关闭连接', async () => {
   const failed = createExportConnection({
     queryError: new Error('connect 127.0.0.1 password=not-for-logs'),