AI agents in Microsoft Teams – how to build an internal assistant for HR, IT and finance

In companies that work in Microsoft 365, employees already spend much of their day in Teams: talking, sharing files and approving requests. An assistant available in the same window needs no extra sign-in and no new program to learn. Employees write to it as they would to a colleague.

The second advantage is mobile access. Teams runs on computers, in the browser and as a mobile app, so a site manager or a salesperson on the road has the assistant to hand. There is no need to build a separate app.

The third advantage is security. The assistant works within the Microsoft 365 accounts and permissions the company already has. This makes it easier to get started, but it also means the assistant inherits every existing permissions mistake, as we explain below.

Microsoft offers three options, which differ in cost, scope and the amount of preparation needed. The table below shows the differences. Most mid-sized companies combine the first two: Copilot for some employees and a few custom assistants for departments.

Even off-the-shelf Copilot does not work well without preparation. Before you switch it on, you need to review file permissions and label confidential documents, because Copilot will find everything an employee has access to.

Copilot Studio is Microsoft’s tool for building custom AI assistants without coding. An assistant has three parts, described in the list below. Each one can be changed without rebuilding the whole thing.

An important distinction: the assistant does not learn from company documents. When asked a question, it searches them for the answer and shows the source. Microsoft states that company data and conversation content are not used to train models, and when you change a policy, the assistant uses the new version straight away.

Below are the four most common uses. For each, we give typical questions, tasks, a condition for success and a limit the assistant should not cross.

The first choice is most often HR or the IT help desk. Both departments get many repetitive questions, have documented rules and a low cost of error. A sales assistant offers a lot, but it requires a well-maintained CRM system, which many companies lack.

The cost is made up of licences, preparation and maintenance. Licences depend on who will use the assistant. If an employee has Microsoft 365 Copilot, their conversations with the assistant in Teams that are based on company data do not use up Copilot Studio credits. Other employees use the assistant through credits bought for the whole company.

Credits are bought in monthly packs, or you pay for actual usage through an Azure subscription. Unused credits from a pack expire at the end of the month. That is why it is safer to pay for usage at the start, and buy a pack once you know the real volume.

Preparation is mainly work on documents, describing the tasks and connecting to systems such as HR or accounting software. Maintenance means a few hours a month from someone who reviews unanswered questions and updates documents.

A simple estimate will show whether it pays off. Suppose the HR department in a company of 200 people receives 250 questions a month and each takes 6 minutes. That is 1,500 minutes, or 25 hours a month. If the assistant takes over half the questions, at a labour cost of PLN 70 an hour, the saving is about PLN 875 a month. 125 conversations at about 4 credits each come to 500 credits, a small fraction of a pack. In an example like this, the main cost is therefore preparing documents and maintenance, not licences.

The assistant has access to company data and can perform tasks in systems. It therefore needs to be treated like any other company system. The list below gathers the questions worth asking before launch, with answers for Microsoft solutions.

Some safeguards work out of the box; others have to be configured. Protection against exposing PESEL numbers (Polish personal identification numbers) or payment card data is not on by default. An administrator has to create the relevant policies in Microsoft Purview, the data protection tool in Microsoft 365.

The most common reason for failure is not technical. The assistant works, but employees keep emailing HR, because they do not know what they can ask it or the first answer disappointed them.

A simple announcement helps, with examples of questions that work and of those that still need a person. The assistant can also send reminders at the right moment, for example “You have 6 days of annual leave left before the end of the year – shall we plan them?”. However, such messages should be used sparingly so they do not turn into spam.

Every answer should have a rating button. The responsible person in the department reviews poorly rated answers and unanswered questions every week, and then improves the documents. Each department should have one person who knows the assistant, helps colleagues and reports problems.

The first assistant should be narrow: one department, a few types of questions, one or two tasks. A broader scope lengthens preparation and makes it harder to assess the results. The list below sets out the steps.

You do not need an assistant if the department gets a few questions a week. A good intranet page setting out the rules is enough. Nor does it make sense when policies are out of date and only one person in the department knows the real rules.

The mistakes in the list below come up most often. Most can be avoided if the assistant is treated like a new member of the department, not like a program you install once.