diff --git a/metagpt/utils/mermaid.py b/metagpt/utils/mermaid.py
index 713f49601..b13199a93 100644
--- a/metagpt/utils/mermaid.py
+++ b/metagpt/utils/mermaid.py
@@ -13,8 +13,7 @@ from metagpt.const import PROJECT_ROOT
 from metagpt.logs import logger
 from metagpt.utils.common import check_cmd_exists
 import os
-
-
+import sys
 
 def mermaid_to_file(mermaid_code, output_file_without_suffix, width=2048, height=2048) -> int:
     """suffix: png/svg/pdf
@@ -28,13 +27,12 @@ def mermaid_to_file(mermaid_code, output_file_without_suffix, width=2048, height
     # Write the Mermaid code to a temporary file
     tmp = Path(f"{output_file_without_suffix}.mmd")
     tmp.write_text(mermaid_code, encoding="utf-8")
-
-    if check_cmd_exists("mmdc") != 0:
-        logger.warning("RUN `npm install -g @mermaid-js/mermaid-cli` to install mmdc")
-        return -1
     engine = CONFIG.mermaid_engine.lower()
-
     if engine == "nodejs":
+        if check_cmd_exists("mmdc") != 0:
+            logger.warning("RUN `npm install -g @mermaid-js/mermaid-cli` to install mmdc")
+            return -1
+        
         for suffix in ["pdf", "svg", "png"]:
             output_file = f"{output_file_without_suffix}.{suffix}"
             # Call the `mmdc` command to convert the Mermaid code to a PNG
@@ -59,12 +57,12 @@ def mermaid_to_file(mermaid_code, output_file_without_suffix, width=2048, height
             else:
                 subprocess.run([CONFIG.mmdc, "-i", str(tmp), "-o", output_file, "-w", str(width), "-H", str(height)])
     else:
-        if engine not in ['playwright', 'puppeteer', 'ink']:
+        if engine not in ['playwright', 'pyppeteer', 'ink']:
             logger.warning(f"Unsupported mermaid engine: {engine}")
             return -1
         __dirname = os.path.dirname(os.path.abspath(__file__))
         module_path = os.path.join(__dirname, f'mmdc_{engine}.py')
-        import sys
+        
         # 构建命令行参数
         command = [
             sys.executable,