LangChain sample agent fails to build

[rido-min]

Following the article https://learn.microsoft.com/en-us/microsoft-agent-365/developer/quickstart-nodejs-langchain

Created the LangChain sample from the toolkit samples gallery

npm run build fails with

> langchain-sample@2025.11.6 build
> tsc

src/client.ts:37:3 - error TS2769: No overload matches this call.
  The last overload gave the following error.
    Object literal may only specify known properties, and 'instructions' does not exist in type 'CreateAgentParams<Record<string, any>, undefined, AnyAnnotationRoot, ResponseFormat> & { responseFormat: ResponseFormat; middleware?: readonly AgentMiddleware<...>[] | undefined; }'.

37   instructions: `You are a helpful assistant with access to tools.
     ~~~~~~~~~~~~

  node_modules/langchain/dist/agents/index.d.cts:183:18
    183 declare function createAgent<StructuredResponseFormat extends Record<string, any> = Record<string, any>, StateSchema extends AnyAnnotationRoot | InteropZodObject | undefined = undefined, ContextSchema extends AnyAnnotationRoot | InteropZodObject = AnyAnnotationRoot, const TMiddleware extends readonly AgentMiddleware[] = readonly AgentMiddleware[]>(params: CreateAgentParams<StructuredResponseFormat, StateSchema, ContextSchema, ResponseFormat> & {
                         ~~~~~~~~~~~
    The last overload is declared here.

src/client.ts:73:43 - error TS2554: Expected 5 arguments, but got 4.
                                             ~~~~~~~~~~~~~~~~~~~~~

  node_modules/@microsoft/agents-a365-tooling-extensions-langchain/dist/esm/McpToolRegistrationService.d.ts:19:127
    19     addToolServersToAgent(agent: ReactAgent, authorization: Authorization, authHandlerName: string, turnContext: TurnContext, authToken: string): Promise<ReactAgent>;   
                                                                                                                                     ~~~~~~~~~~~~~~~~~
    An argument for 'authToken' was not provided.


Found 2 errors in the same file, starting at: src/client.ts:37

[m365-agent-toolkit-assistant]

👋 Hi @rido-min,

Thank you for reporting this issue! We want to let you know that:

⏱️ Our team will personally review your issue
🎯 You can expect a response within 2 business days

✨ This is an AI-generated initial response
🤖 AI-Generated Preliminary Analysis:

Your issue is caused by API surface changes in either the LangChain or Microsoft 365 Agents Toolkit samples.

1. Error instructions does not exist in type 'CreateAgentParams'

• The LangChain API likely changed. Recent LangChain agents do not accept an instructions property in the agent config object.
  Solution:
• Remove or rename instructions in createAgent({ ... }). Consult LangChain docs for agents’ current config properties.

2. addToolServersToAgent: Expected 5 arguments, but got 4

• The extension now requires an authToken parameter.
  Solution:
• Update the call to include the missing authToken as the 5th argument:

  addToolServersToAgent(agent, authorization, authHandlerName, turnContext, authToken);

Actions:

• Update the sample to match the latest APIs.
• Check you have the latest Agents Toolkit, LangChain, and extensions.
• If errors persist, provide your development environment and toolkit versions.

Reference: Agents Toolkit issue #14772

✨We'd love your feedback! Please take a moment to fill out our survey.

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Note: This is an automated first response generated by AI. A human team member will review your issue and provide a more detailed response soon. We appreciate your patience!