# In LangChain, when converting MCP tools to StructuredTool, the langchain-mcp-adapters currently ignore the output schema of MCP tools, making it unable to transfer the MCP tool's output schema to Langgraph nodes' output messages

**URL:** <https://forum.langchain.com/t/in-langchain-when-converting-mcp-tools-to-structuredtool-the-langchain-mcp-adapters-currently-ignore-the-output-schema-of-mcp-tools-making-it-unable-to-transfer-the-mcp-tools-output-schema-to-langgraph-nodes-output-messages/1908>\
**Category:** LangChain Academy\
**Created:** [October 23, 2025, 5:59am UTC](https://forum.langchain.com/t/in-langchain-when-converting-mcp-tools-to-structuredtool-the-langchain-mcp-adapters-currently-ignore-the-output-schema-of-mcp-tools-making-it-unable-to-transfer-the-mcp-tools-output-schema-to-langgraph-nodes-output-messages/1908 "2025-10-23T05:59:31Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![dai-jie](https://yyz1.discourse-cdn.com/flex007/user_avatar/forum.langchain.com/dai-jie/32/1349_2.png) [@dai-jie](https://forum.langchain.com/u/dai-jie)\
**Post date:** [October 23, 2025, 5:59am UTC](https://forum.langchain.com/t/in-langchain-when-converting-mcp-tools-to-structuredtool-the-langchain-mcp-adapters-currently-ignore-the-output-schema-of-mcp-tools-making-it-unable-to-transfer-the-mcp-tools-output-schema-to-langgraph-nodes-output-messages/1908/1 "2025-10-23T05:59:31Z")

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The MCP tool contains an output schema to describe the structure of tool’s output. But I found that langchain StructuredTool does not contain similar properties. when converting to StructuredTool, langchain-mcp-adapters ignores the outputSchema of mcps tools. Is there any way to read mcp tool’s output schema to langgraph node’s output message?

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**Author:** ![dai-jie](https://yyz1.discourse-cdn.com/flex007/user_avatar/forum.langchain.com/dai-jie/32/1349_2.png) [@dai-jie](https://forum.langchain.com/u/dai-jie)\
**Post date:** [October 23, 2025, 6:01am UTC](https://forum.langchain.com/t/in-langchain-when-converting-mcp-tools-to-structuredtool-the-langchain-mcp-adapters-currently-ignore-the-output-schema-of-mcp-tools-making-it-unable-to-transfer-the-mcp-tools-output-schema-to-langgraph-nodes-output-messages/1908/2 "2025-10-23T06:01:47Z")

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![image](https://canada1.discourse-cdn.com/flex007/uploads/langchain/original/2X/d/df00c96f6403740ba5f6039c11e73c9a1f89ea9f.png)