TypeError: Cannot read properties of undefined (reading 'content')-20250507

[NadamHL]

Describe the problem/error/question

Stack trace

TypeError: Cannot read properties of undefined (reading 'content') at ToolCallingAgentOutputParser._baseMessageToString (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/output_parsers/base.cjs:24:31) at ToolCallingAgentOutputParser._callWithConfig (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/output_parsers/base.cjs:49:32) at ToolCallingAgentOutputParser._callWithConfig (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/runnables/base.cjs:223:34) at processTicksAndRejections (node:internal/process/task_queues:95:5) at ToolCallingAgentOutputParser._streamIterator (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/runnables/base.cjs:165:9) at ToolCallingAgentOutputParser.transform (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/runnables/base.cjs:402:9) at RunnableSequence._streamIterator (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/runnables/base.cjs:1320:30) at RunnableSequence.transform (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/runnables/base.cjs:402:9) at wrapInputForTracing (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/runnables/base.cjs:275:30) at pipeGeneratorWithSetup (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/utils/stream.cjs:271:19) at RunnableLambda._transformStreamWithConfig (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/runnables/base.cjs:296:26) at wrapInputForTracing (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/runnables/base.cjs:275:30) at pipeGeneratorWithSetup (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/utils/stream.cjs:271:19) at RunnableLambda._transformStreamWithConfig (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/runnables/base.cjs:296:26) at RunnableSequence._streamIterator (/usr/local/lib/node_modules/n8n/node_modules/@langchain/core/dist/runnables/base.cjs:1320:30)

What is the error message (if any)?

Please share your workflow

Share the output returned by the last node

Information on your n8n setup

• n8n version: 1.91.2
• Database (default: SQLite): sqlite
• n8n EXECUTIONS_PROCESS setting (default: own, main): main
• Running n8n via (Docker, npm, n8n cloud, desktop app): docker
• Operating system: centos 7.9

[NadamHL]

I tried to build a self-built agent for chat model, and the aiagent visited the self-built agent, and indirectly visited the chat model of openai or deepseek. The data formats returned by self-built proxy and direct access to chat model are normal, but there is always no content in error. The following is the data returned by our access interface /v1/chat/completions:

{
“id”: “943b2464-b3e4-49a6-a69c-dafdafa23e2”,
“object”: “chat.completion”,
“created”: 1746524189,
“model”: “deepseek-chat”,
“choices”: [
{
“index”: 0,
“message”: {
“role”: “assistant”,
“content”: “”,
“tool_calls”: [
{
“index”: 0,
“id”: “call_0_1c581ecb-a6a1-4d70-870a-dasfdasfa”,
“type”: “function”,
“function”: {
“name”: “ai_security_knowledge_base_tool”,
“arguments”: “{"input":"[0000-0000]重点业务错误码100001的处理步骤"}”
}
}
]
},
“logprobs”: null,
“finish_reason”: “tool_calls”
}
],
“usage”: {
“prompt_tokens”: 520,
“completion_tokens”: 41,
“total_tokens”: 561,
“prompt_tokens_details”: {
“cached_tokens”: 512
},
“prompt_cache_hit_tokens”: 512,
“prompt_cache_miss_tokens”: 8
},
“system_fingerprint”: “fp_8802369eaa_prod0425fp8”
}

[NadamHL]

The following is the core logic of our proxy service implementation, which will get the response from deepseek and return it directly to the aiagent. :

// 转发至deepseek

func forwardToDeepseek(w http.ResponseWriter, req APIRequest) {
	body, err := json.Marshal(req)
	if err != nil {
		sendError(w, http.StatusInternalServerError, "Failed to marshal request")
		return
	}
	httpReq, _ := http.NewRequest("POST", "https://api.deepseek.com/v1/chat/completions", bytes.NewReader(body))
	httpReq.Header.Set("Authorization", "Bearer "+"sk-12312312dassdw123123")
	httpReq.Header.Set("Content-Type", "application/json")
	httpReq.Header.Set("Accept", "application/json")

	client := &http.Client{Timeout: 30 * time.Second}
	resp, err := client.Do(httpReq)
	if err != nil {
		sendError(w, http.StatusBadGateway, "OpenAI service error")
		return
	}
	defer resp.Body.Close()

	t, _ := ioutil.ReadAll(resp.Body)

	// 返回字符串
	fmt.Fprintf(w, string(t))

}

[For_Gm]

me too
do you have contract?