diff --git a/packages/service/common/s3/validation/upload.ts b/packages/service/common/s3/validation/upload.ts
index fbbf49785e..c863f42668 100644
--- a/packages/service/common/s3/validation/upload.ts
+++ b/packages/service/common/s3/validation/upload.ts
@@ -4,6 +4,7 @@ import path from 'node:path';
 import type { UploadConstraints } from '../contracts/type';
 import { DEFAULT_CONTENT_TYPE, resolveMimeType } from '../utils/mime';
 import { normalizeAllowedExtensions, normalizeFileExtension } from '../utils/uploadConstraints';
+import { env } from '../../../env';
 
 const defaultInspectBytes = 8192;
 const officeZipInspectBytes = 64 * 1024;
@@ -171,6 +172,14 @@ export async function validateUploadFile({
     extension,
     uploadConstraints
   });
+
+  if (env.SKIP_FILE_TYPE_CHECK) {
+    return {
+      filename: normalizedFileName,
+      contentType: expectedMime
+    };
+  }
+
   const detected = await fileTypeFromBuffer(buffer).catch((error) => {
     if (error?.name === 'EndOfStreamError' || error?.message === 'End-Of-Stream') {
       return undefined;
diff --git a/packages/service/env.ts b/packages/service/env.ts
index e584c7ea55..6e5384fe36 100644
--- a/packages/service/env.ts
+++ b/packages/service/env.ts
@@ -1,9 +1,10 @@
 import { createEnv } from '@t3-oss/env-core';
 import z from 'zod';
 
+const truthyBoolStrs = ['true', '1', 'yes', 'y'];
 const BoolSchema = z
   .string()
-  .transform((val) => val === 'true')
+  .transform((val) => truthyBoolStrs.includes(val.toLowerCase()))
   .pipe(z.boolean());
 
 const NumSchema = z.coerce.number<number>();
@@ -17,6 +18,7 @@ const StorageCosProtocolSchema = z.enum(['https:', 'http:']);
 export const env = createEnv({
   server: {
     FILE_TOKEN_KEY: z.string().min(6, 'FILE_TOKEN_KEY must be at least 6 characters'),
+
     // ===== Agent sandbox =====
     AGENT_SANDBOX_PROVIDER: z.enum(['sealosdevbox', 'opensandbox', 'e2b']).optional(),
     AGENT_SANDBOX_E2B_API_KEY: z.string().optional(),
@@ -124,7 +126,9 @@ export const env = createEnv({
     SHOW_SKILL: BoolSchema.default(false),
 
     // Agent engine selection: 'default' uses the built-in Plan+Step engine, 'pi' uses pi-agent-core
-    AGENT_ENGINE: z.enum(['default', 'pi']).default('default')
+    AGENT_ENGINE: z.enum(['default', 'pi']).default('default'),
+
+    SKIP_FILE_TYPE_CHECK: BoolSchema.default(false)
   },
   emptyStringAsUndefined: true,
   runtimeEnv: process.env,